/* * Copyright (c) 1997, 2022, 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. *
*/
//--------------------------------------------------------------------------------- // NMethod statistics // They are printed under various flags, including: // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation. // (In the latter two cases, they like other stats are printed to the log only.)
#ifndef PRODUCT // These variables are put into one block to reduce relocations // and make it simpler to print from the debugger. struct java_nmethod_stats_struct { int nmethod_count; int total_size; int relocation_size; int consts_size; int insts_size; int stub_size; int scopes_data_size; int scopes_pcs_size; int dependencies_size; int handler_table_size; int nul_chk_table_size; #if INCLUDE_JVMCI int speculations_size; int jvmci_data_size; #endif int oops_size; int metadata_size;
void note_nmethod(nmethod* nm) {
nmethod_count += 1;
total_size += nm->size();
relocation_size += nm->relocation_size();
consts_size += nm->consts_size();
insts_size += nm->insts_size();
stub_size += nm->stub_size();
oops_size += nm->oops_size();
metadata_size += nm->metadata_size();
scopes_data_size += nm->scopes_data_size();
scopes_pcs_size += nm->scopes_pcs_size();
dependencies_size += nm->dependencies_size();
handler_table_size += nm->handler_table_size();
nul_chk_table_size += nm->nul_chk_table_size(); #if INCLUDE_JVMCI
speculations_size += nm->speculations_size();
jvmci_data_size += nm->jvmci_data_size(); #endif
} void print_nmethod_stats(constchar* name) { if (nmethod_count == 0) return;
tty->print_cr("Statistics for %d bytecoded nmethods for %s:", nmethod_count, name); if (total_size != 0) tty->print_cr(" total in heap = %d", total_size); if (nmethod_count != 0) tty->print_cr(" header = " SIZE_FORMAT, nmethod_count * sizeof(nmethod)); if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size); if (consts_size != 0) tty->print_cr(" constants = %d", consts_size); if (insts_size != 0) tty->print_cr(" main code = %d", insts_size); if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size); if (oops_size != 0) tty->print_cr(" oops = %d", oops_size); if (metadata_size != 0) tty->print_cr(" metadata = %d", metadata_size); if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size); if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size); if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size); if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size); if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size); #if INCLUDE_JVMCI if (speculations_size != 0) tty->print_cr(" speculations = %d", speculations_size); if (jvmci_data_size != 0) tty->print_cr(" JVMCI data = %d", jvmci_data_size); #endif
}
};
struct native_nmethod_stats_struct { int native_nmethod_count; int native_total_size; int native_relocation_size; int native_insts_size; int native_oops_size; int native_metadata_size; void note_native_nmethod(nmethod* nm) {
native_nmethod_count += 1;
native_total_size += nm->size();
native_relocation_size += nm->relocation_size();
native_insts_size += nm->insts_size();
native_oops_size += nm->oops_size();
native_metadata_size += nm->metadata_size();
} void print_native_nmethod_stats() { if (native_nmethod_count == 0) return;
tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count); if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size); if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size); if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size); if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size); if (native_metadata_size != 0) tty->print_cr(" N. metadata = %d", native_metadata_size);
}
};
struct pc_nmethod_stats_struct { int pc_desc_resets; // number of resets (= number of caches) int pc_desc_queries; // queries to nmethod::find_pc_desc int pc_desc_approx; // number of those which have approximate true int pc_desc_repeats; // number of _pc_descs[0] hits int pc_desc_hits; // number of LRU cache hits int pc_desc_tests; // total number of PcDesc examinations int pc_desc_searches; // total number of quasi-binary search steps int pc_desc_adds; // number of LUR cache insertions
ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
assert(pc != NULL, "Must be non null");
assert(exception.not_null(), "Must be non null");
assert(handler != NULL, "Must be non null");
address ExceptionCache::match(Handle exception, address pc) {
assert(pc != NULL,"Must be non null");
assert(exception.not_null(),"Must be non null"); if (exception->klass() == exception_type()) { return (test_address(pc));
}
return NULL;
}
bool ExceptionCache::match_exception_with_space(Handle exception) {
assert(exception.not_null(),"Must be non null"); if (exception->klass() == exception_type() && count() < cache_size) { returntrue;
} returnfalse;
}
address ExceptionCache::test_address(address addr) { int limit = count(); for (int i = 0; i < limit; i++) { if (pc_at(i) == addr) { return handler_at(i);
}
} return NULL;
}
// Helper used by both find_pc_desc methods. staticinlinebool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests); if (!approximate) return pc->pc_offset() == pc_offset; else return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
}
void PcDescCache::reset_to(PcDesc* initial_pc_desc) { if (initial_pc_desc == NULL) {
_pc_descs[0] = NULL; // native method; no PcDescs at all return;
}
NOT_PRODUCT(++pc_nmethod_stats.pc_desc_resets); // reset the cache by filling it with benign (non-null) values
assert(initial_pc_desc->pc_offset() < 0, "must be sentinel"); for (int i = 0; i < cache_size; i++)
_pc_descs[i] = initial_pc_desc;
}
// Note: one might think that caching the most recently // read value separately would be a win, but one would be // wrong. When many threads are updating it, the cache // line it's in would bounce between caches, negating // any benefit.
// In order to prevent race conditions do not load cache elements // repeatedly, but use a local copy:
PcDesc* res;
// Step one: Check the most recently added value.
res = _pc_descs[0]; if (res == NULL) return NULL; // native method; no PcDescs at all if (match_desc(res, pc_offset, approximate)) {
NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats); return res;
}
// Step two: Check the rest of the LRU cache. for (int i = 1; i < cache_size; ++i) {
res = _pc_descs[i]; if (res->pc_offset() < 0) break; // optimization: skip empty cache if (match_desc(res, pc_offset, approximate)) {
NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits); return res;
}
}
// Report failure. return NULL;
}
void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds); // Update the LRU cache by shifting pc_desc forward. for (int i = 0; i < cache_size; i++) {
PcDesc* next = _pc_descs[i];
_pc_descs[i] = pc_desc;
pc_desc = next;
}
}
// adjust pcs_size so that it is a multiple of both oopSize and // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple // of oopSize, then 2*sizeof(PcDesc) is) staticint adjust_pcs_size(int pcs_size) { int nsize = align_up(pcs_size, oopSize); if ((nsize % sizeof(PcDesc)) != 0) {
nsize = pcs_size + sizeof(PcDesc);
}
assert((nsize % oopSize) == 0, "correct alignment"); return nsize;
}
constchar* nmethod::compile_kind() const { if (is_osr_method()) return"osr"; if (method() != NULL && is_native_method()) { if (method()->is_continuation_native_intrinsic()) { return"cnt";
} return"c2n";
} return NULL;
}
// Fill in default values for various flag fields void nmethod::init_defaults() {
_state = not_installed;
_has_flushed_dependencies = 0;
_load_reported = false; // jvmti state
CheckForOopsClosure cfo;
nm->oops_do(&cfo);
assert(!cfo.found_oop(), "no oops allowed");
// We allow an exception for the own Method, but require its class to be permanent.
Method* own_method = nm->method();
CheckForMetadataClosure cfm(/* ignore reference to own Method */ own_method);
nm->metadata_do(&cfm);
assert(!cfm.found_metadata(), "no metadata allowed");
assert(own_method->method_holder()->class_loader_data()->is_permanent_class_loader_data(), "Method's class needs to be permanent");
} #endif
nmethod* nmethod::new_native_nmethod(const methodHandle& method, int compile_id,
CodeBuffer *code_buffer, int vep_offset, int frame_complete, int frame_size,
ByteSize basic_lock_owner_sp_offset,
ByteSize basic_lock_sp_offset,
OopMapSet* oop_maps, int exception_handler) {
code_buffer->finalize_oop_references(method); // create nmethod
nmethod* nm = NULL; int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
{
MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
if (nm != NULL) { #if INCLUDE_JVMCI if (compiler->is_jvmci()) { // Initialize the JVMCINMethodData object inlined into nm
nm->jvmci_nmethod_data()->initialize(nmethod_mirror_index, nmethod_mirror_name, failed_speculations);
} #endif // To make dependency checking during class loading fast, record // the nmethod dependencies in the classes it is dependent on. // This allows the dependency checking code to simply walk the // class hierarchy above the loaded class, checking only nmethods // which are dependent on those classes. The slow way is to // check every nmethod for dependencies which makes it linear in // the number of methods compiled. For applications with a lot // classes the slow way is too slow. for (Dependencies::DepStream deps(nm); deps.next(); ) { if (deps.type() == Dependencies::call_site_target_value) { // CallSite dependencies are managed on per-CallSite instance basis.
oop call_site = deps.argument_oop(0);
MethodHandles::add_dependent_nmethod(call_site, nm);
} else {
Klass* klass = deps.context_type(); if (klass == NULL) { continue; // ignore things like evol_method
} // record this nmethod as dependent on this klass
InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
}
}
NOT_PRODUCT(if (nm != NULL) note_java_nmethod(nm));
}
} // Do verification and logging outside CodeCache_lock. if (nm != NULL) { // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
DEBUG_ONLY(nm->verify();)
nm->log_new_nmethod();
} return nm;
}
// For native wrappers
nmethod::nmethod(
Method* method,
CompilerType type, int nmethod_size, int compile_id,
CodeOffsets* offsets,
CodeBuffer* code_buffer, int frame_size,
ByteSize basic_lock_owner_sp_offset,
ByteSize basic_lock_sp_offset,
OopMapSet* oop_maps )
: CompiledMethod(method, "native nmethod", type, nmethod_size, sizeof(nmethod), code_buffer, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, true),
_unlinked_next(NULL),
_native_receiver_sp_offset(basic_lock_owner_sp_offset),
_native_basic_lock_sp_offset(basic_lock_sp_offset),
_is_unloading_state(0)
{
{ int scopes_data_offset = 0; int deoptimize_offset = 0; int deoptimize_mh_offset = 0;
init_defaults();
_comp_level = CompLevel_none;
_entry_bci = InvocationEntryBci; // We have no exception handler or deopt handler make the // values something that will never match a pc like the nmethod vtable entry
_exception_offset = 0;
_orig_pc_offset = 0;
_gc_epoch = CodeCache::gc_epoch();
// Copy contents of ExceptionHandlerTable to nmethod
handler_table->copy_to(this);
nul_chk_table->copy_to(this);
#if INCLUDE_JVMCI // Copy speculations to nmethod if (speculations_size() != 0) {
memcpy(speculations_begin(), speculations, speculations_len);
} #endif
// we use the information of entry points to find out if a method is // static or non static
assert(compiler->is_c2() || compiler->is_jvmci() ||
_method->is_static() == (entry_point() == _verified_entry_point), " entry points must be same for static methods and vice versa");
}
}
// Print a short set of xml attributes to identify this nmethod. The // output should be embedded in some other element. void nmethod::log_identity(xmlStream* log) const {
log->print(" compile_id='%d'", compile_id()); constchar* nm_kind = compile_kind(); if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
log->print(" compiler='%s'", compiler_name()); if (TieredCompilation) {
log->print(" level='%d'", comp_level());
} #if INCLUDE_JVMCI if (jvmci_nmethod_data() != NULL) { constchar* jvmci_name = jvmci_nmethod_data()->name(); if (jvmci_name != NULL) {
log->print(" jvmci_mirror_name='");
log->text("%s", jvmci_name);
log->print("'");
}
} #endif
}
if (xtty != NULL) {
xtty->tail("print_nmethod");
}
}
// Promote one word from an assembly-time handle to a live embedded oop. inlinevoid nmethod::initialize_immediate_oop(oop* dest, jobject handle) { if (handle == NULL || // As a special case, IC oops are initialized to 1 or -1.
handle == (jobject) Universe::non_oop_word()) {
*(void**)dest = handle;
} else {
*dest = JNIHandles::resolve_non_null(handle);
}
}
// Have to have the same name because it's called by a template void nmethod::copy_values(GrowableArray<jobject>* array) { int length = array->length();
assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
oop* dest = oops_begin(); for (int index = 0 ; index < length; index++) {
initialize_immediate_oop(&dest[index], array->at(index));
}
// Now we can fix up all the oops in the code. We need to do this // in the code because the assembler uses jobjects as placeholders. // The code and relocations have already been initialized by the // CodeBlob constructor, so it is valid even at this early point to // iterate over relocations and patch the code.
fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
}
void nmethod::copy_values(GrowableArray<Metadata*>* array) { int length = array->length();
assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
Metadata** dest = metadata_begin(); for (int index = 0 ; index < length; index++) {
dest[index] = array->at(index);
}
}
void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) { // re-patch all oop-bearing instructions, just in case some oops moved
RelocIterator iter(this, begin, end); while (iter.next()) { if (iter.type() == relocInfo::oop_type) {
oop_Relocation* reloc = iter.oop_reloc(); if (initialize_immediates && reloc->oop_is_immediate()) {
oop* dest = reloc->oop_addr();
initialize_immediate_oop(dest, cast_from_oop<jobject>(*dest));
} // Refresh the oop-related bits of this instruction.
reloc->fix_oop_relocation();
} elseif (iter.type() == relocInfo::metadata_type) {
metadata_Relocation* reloc = iter.metadata_reloc();
reloc->fix_metadata_relocation();
}
}
}
// Make sure that post call nops fill in nmethod offsets eagerly so // we don't have to race with deoptimization
RelocIterator iter(this); while (iter.next()) { if (iter.type() == relocInfo::post_call_nop_type) {
post_call_nop_Relocation* const reloc = iter.post_call_nop_reloc();
address pc = reloc->addr();
install_post_call_nop_displacement(this, pc);
}
}
}
void nmethod::make_deoptimized() { if (!Continuations::enabled()) { return;
}
switch (iter.type()) { case relocInfo::virtual_call_type: case relocInfo::opt_virtual_call_type: {
CompiledIC *ic = CompiledIC_at(&iter);
address pc = ic->end_of_call();
NativePostCallNop* nop = nativePostCallNop_at(pc); if (nop != NULL) {
nop->make_deopt();
}
assert(NativeDeoptInstruction::is_deopt_at(pc), "check"); break;
} case relocInfo::static_call_type: {
CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
address pc = csc->end_of_call();
NativePostCallNop* nop = nativePostCallNop_at(pc); //tty->print_cr(" - static pc %p", pc); if (nop != NULL) {
nop->make_deopt();
} // We can't assert here, there are some calls to stubs / runtime // that have reloc data and doesn't have a post call NOP. //assert(NativeDeoptInstruction::is_deopt_at(pc), "check"); break;
} default: break;
}
} // Don't deopt this again.
mark_deoptimized();
}
bool nmethod::is_maybe_on_stack() { // If the condition below is true, it means that the nmethod was found to // be alive the previous completed marking cycle. return Atomic::load(&_gc_epoch) >= CodeCache::previous_completed_gc_marking_cycle();
}
void nmethod::inc_decompile_count() { if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return; // Could be gated by ProfileTraps, but do not bother...
Method* m = method(); if (m == NULL) return;
MethodData* mdo = m->method_data(); if (mdo == NULL) return; // There is a benign race here. See comments in methodData.hpp.
mdo->inc_decompile_count();
}
void nmethod::invalidate_osr_method() {
assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod"); // Remove from list of active nmethods if (method() != NULL) {
method()->method_holder()->remove_osr_nmethod(this);
}
}
void nmethod::log_state_change() const { if (LogCompilation) { if (xtty != NULL) {
ttyLocker ttyl; // keep the following output all in one block
xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'",
os::current_thread_id());
log_identity(xtty);
xtty->stamp();
xtty->end_elem();
}
}
CompileTask::print_ul(this, "made not entrant"); if (PrintCompilation) {
print_on(tty, "made not entrant");
}
}
// Invalidate code bool nmethod::make_not_entrant() { // This can be called while the system is already at a safepoint which is ok
NoSafepointVerifier nsv;
if (is_unloading()) { // If the nmethod is unloading, then it is already not entrant through // the nmethod entry barriers. No need to do anything; GC will unload it. returnfalse;
}
if (Atomic::load(&_state) == not_entrant) { // Avoid taking the lock if already in required state. // This is safe from races because the state is an end-state, // which the nmethod cannot back out of once entered. // No need for fencing either. returnfalse;
}
{ // Enter critical section. Does not block for safepoint.
MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
if (Atomic::load(&_state) == not_entrant) { // another thread already performed this transition so nothing // to do, but return false to indicate this. returnfalse;
}
if (is_osr_method()) { // This logic is equivalent to the logic below for patching the // verified entry point of regular methods. // this effectively makes the osr nmethod not entrant
invalidate_osr_method();
} else { // The caller can be calling the method statically or through an inline // cache call.
NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
SharedRuntime::get_handle_wrong_method_stub());
}
if (update_recompile_counts()) { // Mark the method as decompiled.
inc_decompile_count();
}
BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod(); if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) { // If nmethod entry barriers are not supported, we won't mark // nmethods as on-stack when they become on-stack. So we // degrade to a less accurate flushing strategy, for now.
mark_as_maybe_on_stack();
}
// Remove nmethod from method.
unlink_from_method();
} // leave critical region under CompiledMethod_lock
#if INCLUDE_JVMCI // Invalidate can't occur while holding the Patching lock
JVMCINMethodData* nmethod_data = jvmci_nmethod_data(); if (nmethod_data != NULL) {
nmethod_data->invalidate_nmethod_mirror(this);
} #endif
#ifdef ASSERT if (is_osr_method() && method() != NULL) { // Make sure osr nmethod is invalidated, i.e. not on the list bool found = method()->method_holder()->remove_osr_nmethod(this);
assert(!found, "osr nmethod should have been invalidated");
} #endif
returntrue;
}
// For concurrent GCs, there must be a handshake between unlink and flush void nmethod::unlink() { if (_unlinked_next != NULL) { // Already unlinked. It can be invoked twice because concurrent code cache // unloading might need to restart when inline cache cleaning fails due to // running out of ICStubs, which can only be refilled at safepoints return;
}
flush_dependencies();
// unlink_from_method will take the CompiledMethod_lock. // In this case we don't strictly need it when unlinking nmethods from // the Method, because it is only concurrently unlinked by // the entry barrier, which acquires the per nmethod lock.
unlink_from_method();
clear_ic_callsites();
if (is_osr_method()) {
invalidate_osr_method();
}
#if INCLUDE_JVMCI // Clear the link between this nmethod and a HotSpotNmethod mirror
JVMCINMethodData* nmethod_data = jvmci_nmethod_data(); if (nmethod_data != NULL) {
nmethod_data->invalidate_nmethod_mirror(this);
} #endif
// Post before flushing as jmethodID is being used
post_compiled_method_unload();
// Register for flushing when it is safe. For concurrent class unloading, // that would be after the unloading handshake, and for STW class unloading // that would be when getting back to the VM thread.
CodeCache::register_unlinked(this);
}
// We need to deallocate any ExceptionCache data. // Note that we do not need to grab the nmethod lock for this, it // better be thread safe if we're disposing of it!
ExceptionCache* ec = exception_cache(); while(ec != NULL) {
ExceptionCache* next = ec->next(); delete ec;
ec = next;
}
// // Notify all classes this nmethod is dependent on that it is no // longer dependent.
void nmethod::flush_dependencies() { if (!has_flushed_dependencies()) {
set_has_flushed_dependencies(); for (Dependencies::DepStream deps(this); deps.next(); ) { if (deps.type() == Dependencies::call_site_target_value) { // CallSite dependencies are managed on per-CallSite instance basis.
oop call_site = deps.argument_oop(0);
MethodHandles::clean_dependency_context(call_site);
} else {
Klass* klass = deps.context_type(); if (klass == NULL) { continue; // ignore things like evol_method
} // During GC liveness of dependee determines class that needs to be updated. // The GC may clean dependency contexts concurrently and in parallel.
InstanceKlass::cast(klass)->clean_dependency_context();
}
}
}
}
// ------------------------------------------------------------------ // post_compiled_method_load_event // new method for install_code() path // Transfer information from compilation to jvmti void nmethod::post_compiled_method_load_event(JvmtiThreadState* state) { // This is a bad time for a safepoint. We don't want // this nmethod to get unloaded while we're queueing the event.
NoSafepointVerifier nsv;
if (JvmtiExport::should_post_compiled_method_load()) { // Only post unload events if load events are found.
set_load_reported(); // If a JavaThread hasn't been passed in, let the Service thread // (which is a real Java thread) post the event
JvmtiDeferredEvent event = JvmtiDeferredEvent::compiled_method_load_event(this); if (state == NULL) { // Execute any barrier code for this nmethod as if it's called, since // keeping it alive looks like stack walking.
run_nmethod_entry_barrier();
ServiceThread::enqueue_deferred_event(&event);
} else { // This enters the nmethod barrier outside in the caller.
state->enqueue_event(&event);
}
}
}
// If a JVMTI agent has enabled the CompiledMethodUnload event then // post the event. The Method* will not be valid when this is freed.
// Don't bother posting the unload if the load event wasn't posted. if (load_reported() && JvmtiExport::should_post_compiled_method_unload()) {
JvmtiDeferredEvent event =
JvmtiDeferredEvent::compiled_method_unload_event(
method()->jmethod_id(), insts_begin());
ServiceThread::enqueue_deferred_event(&event);
}
}
// Iterate over metadata calling this function. Used by RedefineClasses void nmethod::metadata_do(MetadataClosure* f) {
{ // Visit all immediate references that are embedded in the instruction stream.
RelocIterator iter(this, oops_reloc_begin()); while (iter.next()) { if (iter.type() == relocInfo::metadata_type) {
metadata_Relocation* r = iter.metadata_reloc(); // In this metadata, we must only follow those metadatas directly embedded in // the code. Other metadatas (oop_index>0) are seen as part of // the metadata section below.
assert(1 == (r->metadata_is_immediate()) +
(r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()), "metadata must be found in exactly one place"); if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
Metadata* md = r->metadata_value(); if (md != _method) f->do_metadata(md);
}
} elseif (iter.type() == relocInfo::virtual_call_type) { // Check compiledIC holders associated with this nmethod
ResourceMark rm;
CompiledIC *ic = CompiledIC_at(&iter); if (ic->is_icholder_call()) {
CompiledICHolder* cichk = ic->cached_icholder();
f->do_metadata(cichk->holder_metadata());
f->do_metadata(cichk->holder_klass());
} else {
Metadata* ic_oop = ic->cached_metadata(); if (ic_oop != NULL) {
f->do_metadata(ic_oop);
}
}
}
}
}
// Visit the metadata section for (Metadata** p = metadata_begin(); p < metadata_end(); p++) { if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
Metadata* md = *p;
f->do_metadata(md);
}
// Visit metadata not embedded in the other places. if (_method != NULL) f->do_metadata(_method);
}
// Heuristic for nuking nmethods even though their oops are live. // Main purpose is to reduce code cache pressure and get rid of // nmethods that don't seem to be all that relevant any longer. bool nmethod::is_cold() { if (!MethodFlushing || is_native_method() || is_not_installed()) { // No heuristic unloading at all returnfalse;
}
if (!is_maybe_on_stack() && is_not_entrant()) { // Not entrant nmethods that are not on any stack can just // be removed returntrue;
}
BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod(); if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) { // On platforms that don't support nmethod entry barriers, we can't // trust the temporal aspect of the gc epochs. So we can't detect // cold nmethods on such platforms. returnfalse;
}
if (!UseCodeCacheFlushing) { // Bail out if we don't heuristically remove nmethods returnfalse;
}
// Other code can be phased out more gradually after N GCs return CodeCache::previous_completed_gc_marking_cycle() > _gc_epoch + 2 * CodeCache::cold_gc_count();
}
// The _is_unloading_state encodes a tuple comprising the unloading cycle // and the result of IsUnloadingBehaviour::is_unloading() for that cycle. // This is the bit layout of the _is_unloading_state byte: 00000CCU // CC refers to the cycle, which has 2 bits, and U refers to the result of // IsUnloadingBehaviour::is_unloading() for that unloading cycle.
// The IsUnloadingBehaviour is responsible for calculating if the nmethod // should be unloaded. This can be either because there is a dead oop, // or because is_cold() heuristically determines it is time to unload.
state_unloading_cycle = current_cycle;
state_is_unloading = IsUnloadingBehaviour::is_unloading(this);
uint8_t new_state = IsUnloadingState::create(state_is_unloading, state_unloading_cycle);
// Note that if an nmethod has dead oops, everyone will agree that the // nmethod is_unloading. However, the is_cold heuristics can yield // different outcomes, so we guard the computed result with a CAS // to ensure all threads have a shared view of whether an nmethod // is_unloading or not.
uint8_t found_state = Atomic::cmpxchg(&_is_unloading_state, state, new_state, memory_order_relaxed);
if (found_state == state) { // First to change state, we win return state_is_unloading;
} else { // State already set, so use it return IsUnloadingState::is_unloading(found_state);
}
}
// This is called at the end of the strong tracing/marking phase of a // GC to unload an nmethod if it contains otherwise unreachable // oops or is heuristically found to be not important. void nmethod::do_unloading(bool unloading_occurred) { // Make sure the oop's ready to receive visitors if (is_unloading()) {
unlink();
} else {
guarantee(unload_nmethod_caches(unloading_occurred), "Should not need transition stubs");
BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod(); if (bs_nm != NULL) {
bs_nm->disarm(this);
}
}
}
void nmethod::oops_do(OopClosure* f, bool allow_dead) { // Prevent extra code cache walk for platforms that don't have immediate oops. if (relocInfo::mustIterateImmediateOopsInCode()) {
RelocIterator iter(this, oops_reloc_begin());
while (iter.next()) { if (iter.type() == relocInfo::oop_type ) {
oop_Relocation* r = iter.oop_reloc(); // In this loop, we must only follow those oops directly embedded in // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
assert(1 == (r->oop_is_immediate()) +
(r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), "oop must be found in exactly one place"); if (r->oop_is_immediate() && r->oop_value() != NULL) {
f->do_oop(r->oop_addr());
}
}
}
}
// Scopes // This includes oop constants not inlined in the code stream. for (oop* p = oops_begin(); p < oops_end(); p++) { if (*p == Universe::non_oop_word()) continue; // skip non-oops
f->do_oop(p);
}
}
void nmethod::follow_nmethod(OopIterateClosure* cl) { // Process oops in the nmethod
oops_do(cl);
// CodeCache unloading support
mark_as_maybe_on_stack();
bool nmethod::oops_do_try_claim() { if (oops_do_try_claim_weak_request()) {
nmethod* result = oops_do_try_add_to_list_as_weak_done();
assert(result == NULL, "adding to global list as weak done must always succeed."); returntrue;
} returnfalse;
}
bool nmethod::oops_do_try_claim_weak_request() {
assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
if ((_oops_do_mark_link == NULL) &&
(Atomic::replace_if_null(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag)))) {
oops_do_log_change("oops_do, mark weak request"); returntrue;
} returnfalse;
}
nmethod::oops_do_mark_link* nmethod::oops_do_try_add_strong_request(nmethod::oops_do_mark_link* next) {
assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
assert(next == mark_link(this, claim_weak_request_tag), "Should be claimed as weak");
oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, next, mark_link(this, claim_strong_request_tag)); if (old_next == next) {
oops_do_log_change("oops_do, mark strong request");
} return old_next;
}
bool nmethod::oops_do_try_claim_weak_done_as_strong_done(nmethod::oops_do_mark_link* next) {
assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
assert(extract_state(next) == claim_weak_done_tag, "Should be claimed as weak done");
oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, next, mark_link(extract_nmethod(next), claim_strong_done_tag)); if (old_next == next) {
oops_do_log_change("oops_do, mark weak done -> mark strong done"); returntrue;
} returnfalse;
}
nmethod* nmethod::oops_do_try_add_to_list_as_weak_done() {
assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
assert(extract_state(_oops_do_mark_link) == claim_weak_request_tag ||
extract_state(_oops_do_mark_link) == claim_strong_request_tag, "must be but is nmethod " PTR_FORMAT " %u", p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
nmethod* old_head = Atomic::xchg(&_oops_do_mark_nmethods, this); // Self-loop if needed. if (old_head == NULL) {
old_head = this;
} // Try to install end of list and weak done tag. if (Atomic::cmpxchg(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag), mark_link(old_head, claim_weak_done_tag)) == mark_link(this, claim_weak_request_tag)) {
oops_do_log_change("oops_do, mark weak done"); return NULL;
} else { return old_head;
}
}
void nmethod::oops_do_add_to_list_as_strong_done() {
assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
nmethod* old_head = Atomic::xchg(&_oops_do_mark_nmethods, this); // Self-loop if needed. if (old_head == NULL) {
old_head = this;
}
assert(_oops_do_mark_link == mark_link(this, claim_strong_done_tag), "must be but is nmethod " PTR_FORMAT " state %u",
p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
oops_do_set_strong_done(old_head);
}
void nmethod::oops_do_process_weak(OopsDoProcessor* p) { if (!oops_do_try_claim_weak_request()) { // Failed to claim for weak processing.
oops_do_log_change("oops_do, mark weak request fail"); return;
}
p->do_regular_processing(this);
nmethod* old_head = oops_do_try_add_to_list_as_weak_done(); if (old_head == NULL) { return;
}
oops_do_log_change("oops_do, mark weak done fail"); // Adding to global list failed, another thread added a strong request.
assert(extract_state(_oops_do_mark_link) == claim_strong_request_tag, "must be but is %u", extract_state(_oops_do_mark_link));
oops_do_log_change("oops_do, mark weak request -> mark strong done");
oops_do_set_strong_done(old_head); // Do missing strong processing.
p->do_remaining_strong_processing(this);
}
void nmethod::oops_do_process_strong(OopsDoProcessor* p) {
oops_do_mark_link* next_raw = oops_do_try_claim_strong_done(); if (next_raw == NULL) {
p->do_regular_processing(this);
oops_do_add_to_list_as_strong_done(); return;
} // Claim failed. Figure out why and handle it. if (oops_do_has_weak_request(next_raw)) {
oops_do_mark_link* old = next_raw; // Claim failed because being weak processed (state == "weak request"). // Try to request deferred strong processing.
next_raw = oops_do_try_add_strong_request(old); if (next_raw == old) { // Successfully requested deferred strong processing. return;
} // Failed because of a concurrent transition. No longer in "weak request" state.
} if (oops_do_has_any_strong_state(next_raw)) { // Already claimed for strong processing or requested for such. return;
} if (oops_do_try_claim_weak_done_as_strong_done(next_raw)) { // Successfully claimed "weak done" as "strong done". Do the missing marking.
p->do_remaining_strong_processing(this); return;
} // Claim failed, some other thread got it.
}
nmethod* next = _oops_do_mark_nmethods;
_oops_do_mark_nmethods = NULL; if (next != NULL) {
nmethod* cur; do {
cur = next;
next = extract_nmethod(cur->_oops_do_mark_link);
cur->_oops_do_mark_link = NULL;
DEBUG_ONLY(cur->verify_oop_relocations());
LogTarget(Trace, gc, nmethod) lt; if (lt.is_enabled()) {
LogStream ls(lt);
CompileTask::print(&ls, cur, "oops_do, unmark", /*short_form:*/ true);
} // End if self-loop has been detected.
} while (cur != next);
}
log_trace(gc, nmethod)("oops_do_marking_epilogue");
}
inlinebool includes(void* p, void* from, void* to) { return from <= p && p < to;
}
void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
assert(count >= 2, "must be sentinel values, at least");
#ifdef ASSERT // must be sorted and unique; we do a binary search in find_pc_desc() int prev_offset = pcs[0].pc_offset();
assert(prev_offset == PcDesc::lower_offset_limit, "must start with a sentinel"); for (int i = 1; i < count; i++) { int this_offset = pcs[i].pc_offset();
assert(this_offset > prev_offset, "offsets must be sorted");
prev_offset = this_offset;
}
assert(prev_offset == PcDesc::upper_offset_limit, "must end with a sentinel"); #endif//ASSERT
// Search for MethodHandle invokes and tag the nmethod. for (int i = 0; i < count; i++) { if (pcs[i].is_method_handle_invoke()) {
set_has_method_handle_invokes(true); break;
}
}
assert(has_method_handle_invokes() == (_deopt_mh_handler_begin != NULL), "must have deopt mh handler");
// Adjust the final sentinel downward.
PcDesc* last_pc = &scopes_pcs_begin()[count-1];
assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
last_pc->set_pc_offset(content_size() + 1); for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) { // Fill any rounding gaps with copies of the last record.
last_pc[1] = last_pc[0];
} // The following assert could fail if sizeof(PcDesc) is not // an integral multiple of oopSize (the rounding term). // If it fails, change the logic to always allocate a multiple // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
}
#ifdef ASSERT static PcDesc* linear_search(const PcDescSearch& search, int pc_offset, bool approximate) {
PcDesc* lower = search.scopes_pcs_begin();
PcDesc* upper = search.scopes_pcs_end();
lower += 1; // exclude initial sentinel
PcDesc* res = NULL; for (PcDesc* p = lower; p < upper; p++) {
NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests); // don't count this call to match_desc if (match_desc(p, pc_offset, approximate)) { if (res == NULL)
res = p; else
res = (PcDesc*) badAddress;
}
} return res;
} #endif
// Finds a PcDesc with real-pc equal to "pc"
PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, const PcDescSearch& search) {
address base_address = search.code_begin(); if ((pc < base_address) ||
(pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) { return NULL; // PC is wildly out of range
} int pc_offset = (int) (pc - base_address);
// Check the PcDesc cache if it contains the desired PcDesc // (This as an almost 100% hit rate.)
PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate); if (res != NULL) {
assert(res == linear_search(search, pc_offset, approximate), "cache ok"); return res;
}
// Fallback algorithm: quasi-linear search for the PcDesc // Find the last pc_offset less than the given offset. // The successor must be the required match, if there is a match at all. // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
PcDesc* lower = search.scopes_pcs_begin();
PcDesc* upper = search.scopes_pcs_end();
upper -= 1; // exclude final sentinel if (lower >= upper) return NULL; // native method; no PcDescs at all
#define assert_LU_OK \ /* invariant on lower..upper during the following search: */ \
assert(lower->pc_offset() < pc_offset, "sanity"); \
assert(upper->pc_offset() >= pc_offset, "sanity")
assert_LU_OK;
// Use the last successful return as a split point.
PcDesc* mid = _pc_desc_cache.last_pc_desc();
NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches); if (mid->pc_offset() < pc_offset) {
lower = mid;
} else {
upper = mid;
}
// Take giant steps at first (4096, then 256, then 16, then 1) constint LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1); constint RADIX = (1 << LOG2_RADIX); for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) { while ((mid = lower + step) < upper) {
assert_LU_OK;
NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches); if (mid->pc_offset() < pc_offset) {
lower = mid;
} else {
upper = mid; break;
}
}
assert_LU_OK;
}
// Sneak up on the value with a linear search of length ~16. while (true) {
assert_LU_OK;
mid = lower + 1;
NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches); if (mid->pc_offset() < pc_offset) {
lower = mid;
} else {
upper = mid; break;
}
} #undef assert_LU_OK
// Iterate over live nmethods and check dependencies of all nmethods that are not // marked for deoptimization. A particular dependency is only checked once.
NMethodIterator iter(NMethodIterator::only_not_unloading); while(iter.next()) {
nmethod* nm = iter.method(); // Only notify for live nmethods if (!nm->is_marked_for_deoptimization()) { for (Dependencies::DepStream deps(nm); deps.next(); ) { // Construct abstraction of a dependency.
DependencySignature* current_sig = new DependencySignature(deps);
// Determine if dependency is already checked. table->put(...) returns // 'true' if the dependency is added (i.e., was not in the hashtable). if (table->put(*current_sig, 1)) { if (deps.check_dependency() != NULL) { // Dependency checking failed. Print out information about the failed // dependency and finally fail with an assert. We can fail here, since // dependency checking is never done in a product build.
tty->print_cr("Failed dependency:");
changes.print();
nm->print();
nm->print_dependencies();
assert(false, "Should have been marked for deoptimization");
}
}
}
}
}
}
bool nmethod::check_dependency_on(DepChange& changes) { // What has happened: // 1) a new class dependee has been added // 2) dependee and all its super classes have been marked bool found_check = false; // set true if we are upset for (Dependencies::DepStream deps(this); deps.next(); ) { // Evaluate only relevant dependencies. if (deps.spot_check_dependency_at(changes) != NULL) {
found_check = true;
NOT_DEBUG(break);
}
} return found_check;
}
// Called from mark_for_deoptimization, when dependee is invalidated. bool nmethod::is_dependent_on_method(Method* dependee) { for (Dependencies::DepStream deps(this); deps.next(); ) { if (deps.type() != Dependencies::evol_method) continue;
Method* method = deps.method_argument(0); if (method == dependee) returntrue;
} returnfalse;
}
void nmethod_init() { // make sure you didn't forget to adjust the filler fields
assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
}
class VerifyOopsClosure: public OopClosure {
nmethod* _nm; bool _ok; public:
VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { } bool ok() { return _ok; } virtualvoid do_oop(oop* p) { if (oopDesc::is_oop_or_null(*p)) return; // Print diagnostic information before calling print_nmethod(). // Assertions therein might prevent call from returning.
tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm)); if (_ok) {
_nm->print_nmethod(true);
_ok = false;
}
} virtualvoid do_oop(narrowOop* p) { ShouldNotReachHere(); }
};
class VerifyMetadataClosure: public MetadataClosure { public: void do_metadata(Metadata* md) { if (md->is_method()) {
Method* method = (Method*)md;
assert(!method->is_old(), "Should not be installing old methods");
}
}
};
void nmethod::verify() { if (is_not_entrant()) return;
// Make sure all the entry points are correctly aligned for patching.
NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
// assert(oopDesc::is_oop(method()), "must be valid");
ResourceMark rm;
if (!CodeCache::contains(this)) {
fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
}
if(is_native_method() ) return;
nmethod* nm = CodeCache::find_nmethod(verified_entry_point()); if (nm != this) {
fatal("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
}
for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { if (! p->verify(this)) {
tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
}
}
#ifdef ASSERT #if INCLUDE_JVMCI
{ // Verify that implicit exceptions that deoptimize have a PcDesc and OopMap
ImmutableOopMapSet* oms = oop_maps();
ImplicitExceptionTable implicit_table(this); for (uint i = 0; i < implicit_table.len(); i++) { int exec_offset = (int) implicit_table.get_exec_offset(i); if (implicit_table.get_exec_offset(i) == implicit_table.get_cont_offset(i)) {
assert(pc_desc_at(code_begin() + exec_offset) != NULL, "missing PcDesc"); bool found = false; for (int i = 0, imax = oms->count(); i < imax; i++) { if (oms->pair_at(i)->pc_offset() == exec_offset) {
found = true; break;
}
}
assert(found, "missing oopmap");
}
}
} #endif #endif
VerifyOopsClosure voc(this);
oops_do(&voc);
assert(voc.ok(), "embedded oops must be OK");
Universe::heap()->verify_nmethod(this);
assert(_oops_do_mark_link == NULL, "_oops_do_mark_link for %s should be NULL but is " PTR_FORMAT,
nm->method()->external_name(), p2i(_oops_do_mark_link));
verify_scopes();
// Verify IC only when nmethod installation is finished. if (!is_not_installed()) { if (CompiledICLocker::is_safe(this)) {
CompiledIC_at(this, call_site);
} else {
CompiledICLocker ml_verify(this);
CompiledIC_at(this, call_site);
}
}
HandleMark hm(Thread::current());
PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
assert(pd != NULL, "PcDesc must exist"); for (ScopeDesc* sd = new ScopeDesc(this, pd);
!sd->is_top(); sd = sd->sender()) {
sd->verify();
}
}
void nmethod::verify_scopes() { if( !method() ) return; // Runtime stubs have no scope if (method()->is_native()) return; // Ignore stub methods. // iterate through all interrupt point // and verify the debug information is valid.
RelocIterator iter((nmethod*)this); while (iter.next()) {
address stub = NULL; switch (iter.type()) { case relocInfo::virtual_call_type:
verify_interrupt_point(iter.addr()); break; case relocInfo::opt_virtual_call_type:
stub = iter.opt_virtual_call_reloc()->static_stub();
verify_interrupt_point(iter.addr()); break; case relocInfo::static_call_type:
stub = iter.static_call_reloc()->static_stub(); //verify_interrupt_point(iter.addr()); break; case relocInfo::runtime_call_type: case relocInfo::runtime_call_w_cp_type: {
address destination = iter.reloc()->value(); // Right now there is no way to find out which entries support // an interrupt point. It would be nice if we had this // information in a table. break;
} default: break;
}
assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
}
}
void nmethod::print_code() {
ResourceMark m;
ttyLocker ttyl; // Call the specialized decode method of this class.
decode(tty);
}
#ifndef PRODUCT // called InstanceKlass methods are available only then. Declared as PRODUCT_RETURN
void nmethod::print_dependencies() {
ResourceMark rm;
ttyLocker ttyl; // keep the following output all in one block
tty->print_cr("Dependencies:"); for (Dependencies::DepStream deps(this); deps.next(); ) {
deps.print_dependency();
Klass* ctxk = deps.context_type(); if (ctxk != NULL) { if (ctxk->is_instance_klass() && InstanceKlass::cast(ctxk)->is_dependent_nmethod(this)) {
tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
}
}
deps.log_dependency(); // put it into the xml log also
}
} #endif
#ifdefined(SUPPORT_DATA_STRUCTS)
// Print the oops from the underlying CodeBlob. void nmethod::print_oops(outputStream* st) {
ResourceMark m;
st->print("Oops:"); if (oops_begin() < oops_end()) {
st->cr(); for (oop* p = oops_begin(); p < oops_end(); p++) {
Disassembler::print_location((unsignedchar*)p, (unsignedchar*)oops_begin(), (unsignedchar*)oops_end(), st, true, false);
st->print(PTR_FORMAT " ", *((uintptr_t*)p)); if (Universe::contains_non_oop_word(p)) {
st->print_cr("NON_OOP"); continue; // skip non-oops
} if (*p == NULL) {
st->print_cr("NULL-oop"); continue; // skip non-oops
}
(*p)->print_value_on(st);
st->cr();
}
} else {
st->print_cr(" <list empty>");
}
}
// Print metadata pool. void nmethod::print_metadata(outputStream* st) {
ResourceMark m;
st->print("Metadata:"); if (metadata_begin() < metadata_end()) {
st->cr(); for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
Disassembler::print_location((unsignedchar*)p, (unsignedchar*)metadata_begin(), (unsignedchar*)metadata_end(), st, true, false);
st->print(PTR_FORMAT " ", *((uintptr_t*)p)); if (*p && *p != Universe::non_oop_word()) {
(*p)->print_value_on(st);
}
st->cr();
}
} else {
st->print_cr(" <list empty>");
}
}
#ifndef PRODUCT // ScopeDesc::print_on() is available only then. Declared as PRODUCT_RETURN void nmethod::print_scopes_on(outputStream* st) { // Find the first pc desc for all scopes in the code and print it.
ResourceMark rm;
st->print("scopes:"); if (scopes_pcs_begin() < scopes_pcs_end()) {
st->cr(); for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) { if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null) continue;
#ifndef PRODUCT // RelocIterator does support printing only then. void nmethod::print_relocations() {
ResourceMark m; // in case methods get printed via the debugger
tty->print_cr("relocations:");
RelocIterator iter(this);
iter.print();
} #endif
void nmethod::print_pcs_on(outputStream* st) {
ResourceMark m; // in case methods get printed via debugger
st->print("pc-bytecode offsets:"); if (scopes_pcs_begin() < scopes_pcs_end()) {
st->cr(); for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
p->print_on(st, this); // print output ends with a newline
}
} else {
st->print_cr(" <list empty>");
}
}
void nmethod::print_recorded_oop(int log_n, int i) { void* value;
if (i == 0) {
value = NULL;
} else { // Be careful around non-oop words. Don't create an oop // with that value, or it will assert in verification code. if (Universe::contains_non_oop_word(oop_addr_at(i))) {
value = Universe::non_oop_word();
} else {
value = oop_at(i);
}
}
tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(value));
//---< print CP header to make clear what's printed >--- if( ((uintptr_t)cp&(CP_alignment-1)) == 0 ) {
n = bytes_per_line;
st->print_cr("[Constant Pool]");
Disassembler::print_location(cp, cstart, cend, st, true, true);
Disassembler::print_hexdata(cp, n, st, true);
st->cr();
} else {
n = (uintptr_t)cp&(bytes_per_line-1);
st->print_cr("[Constant Pool (unaligned)]");
}
//---< print CP contents, bytes_per_line at a time >--- while (cp < cend) {
Disassembler::print_location(cp, cstart, cend, st, true, false);
Disassembler::print_hexdata(cp, n, st, false);
cp += n;
n = bytes_per_line;
st->cr();
}
//---< Show potential alignment gap between constant pool and code >---
cend = code_begin(); if( cp < cend ) {
n = 4;
st->print_cr("[Code entry alignment]"); while (cp < cend) {
Disassembler::print_location(cp, cstart, cend, st, false, false);
cp += n;
st->cr();
}
}
} else {
st->print_cr("[Constant Pool (empty)]");
}
st->cr();
}
#endif
// Disassemble this nmethod. // Print additional debug information, if requested. This could be code // comments, block comments, profiling counters, etc. // The undisassembled format is useful no disassembler library is available. // The resulting hex dump (with markers) can be disassembled later, or on // another system, when/where a disassembler library is available. void nmethod::decode2(outputStream* ost) const {
// Called from frame::back_trace_with_decode without ResourceMark.
ResourceMark rm;
// Make sure we have a valid stream to print on.
outputStream* st = ost ? ost : tty;
// Decoding an nmethod can write to a PcDescCache (see PcDescCache::add_pc_desc)
MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, Thread::current());)
st->cr();
this->print(st);
st->cr();
#ifdefined(SUPPORT_ASSEMBLY) //---------------------------------- //---< Print real disassembly >--- //---------------------------------- if (! use_compressed_format) {
st->print_cr("[Disassembly]");
Disassembler::decode(const_cast<nmethod*>(this), st);
st->bol();
st->print_cr("[/Disassembly]"); return;
} #endif
#ifdefined(SUPPORT_ABSTRACT_ASSEMBLY)
// Compressed undisassembled disassembly format. // The following status values are defined/supported: // = 0 - currently at bol() position, nothing printed yet on current line. // = 1 - currently at position after print_location(). // > 1 - in the midst of printing instruction stream bytes. int compressed_format_idx = 0; int code_comment_column = 0; constint instr_maxlen = Assembler::instr_maxlen(); const uint tabspacing = 8; unsignedchar* start = this->code_begin(); unsignedchar* p = this->code_begin(); unsignedchar* end = this->code_end(); unsignedchar* pss = p; // start of a code section (used for offsets)
if ((start == NULL) || (end == NULL)) {
st->print_cr("PrintAssembly not possible due to uninitialized section pointers"); return;
} #endif
#ifdefined(SUPPORT_ABSTRACT_ASSEMBLY) //---< plain abstract disassembly, no comments or anything, just section headers >--- if (use_compressed_format && ! compressed_with_comments) { const_cast<nmethod*>(this)->print_constant_pool(st);
//---< Open the output (Marker for post-mortem disassembler) >---
st->print_cr("[MachCode]"); constchar* header = NULL;
address p0 = p; while (p < end) {
address pp = p; while ((p < end) && (header == NULL)) {
header = nmethod_section_label(p);
pp = p;
p += Assembler::instr_len(p);
} if (pp > p0) {
AbstractDisassembler::decode_range_abstract(p0, pp, start, end, st, Assembler::instr_maxlen());
p0 = pp;
p = pp;
header = NULL;
} elseif (header != NULL) {
st->bol();
st->print_cr("%s", header);
header = NULL;
}
} //---< Close the output (Marker for post-mortem disassembler) >---
st->bol();
st->print_cr("[/MachCode]"); return;
} #endif
#ifdefined(SUPPORT_ABSTRACT_ASSEMBLY) //---< abstract disassembly with comments and section headers merged in >--- if (compressed_with_comments) { const_cast<nmethod*>(this)->print_constant_pool(st);
//---< Open the output (Marker for post-mortem disassembler) >---
st->print_cr("[MachCode]"); while ((p < end) && (p != NULL)) { constint instruction_size_in_bytes = Assembler::instr_len(p);
//---< Block comments for nmethod. Interrupts instruction stream, if any. >--- // Outputs a bol() before and a cr() after, but only if a comment is printed. // Prints nmethod_section_label as well. if (AbstractDisassembler::show_block_comment()) {
print_block_comment(st, p); if (st->position() == 0) {
compressed_format_idx = 0;
}
}
//---< New location information after line break >--- if (compressed_format_idx == 0) {
code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
compressed_format_idx = 1;
}
//---< Code comment for current instruction. Address range [p..(p+len)) >--- unsignedchar* p_end = p + (ssize_t)instruction_size_in_bytes;
S390_ONLY(if (p_end > end) p_end = end;) // avoid getting past the end
if (AbstractDisassembler::show_comment() && const_cast<nmethod*>(this)->has_code_comment(p, p_end)) { //---< interrupt instruction byte stream for code comment >--- if (compressed_format_idx > 1) {
st->cr(); // interrupt byte stream
st->cr(); // add an empty line
code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
} const_cast<nmethod*>(this)->print_code_comment_on(st, code_comment_column, p, p_end );
st->bol();
compressed_format_idx = 0;
}
//---< New location information after line break >--- if (compressed_format_idx == 0) {
code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
compressed_format_idx = 1;
}
//---< Nicely align instructions for readability >--- if (compressed_format_idx > 1) {
Disassembler::print_delimiter(st);
}
//---< Now, finally, print the actual instruction bytes >--- unsignedchar* p0 = p;
p = Disassembler::decode_instruction_abstract(p, st, instruction_size_in_bytes, instr_maxlen);
compressed_format_idx += p - p0;
if (Disassembler::start_newline(compressed_format_idx-1)) {
st->cr();
compressed_format_idx = 0;
}
} //---< Close the output (Marker for post-mortem disassembler) >---
st->bol();
st->print_cr("[/MachCode]"); return;
} #endif
}
// implicit exceptions? int cont_offset = ImplicitExceptionTable(this).continuation_offset(begin - code_begin()); if (cont_offset != 0) returntrue;
returnfalse;
}
void nmethod::print_code_comment_on(outputStream* st, int column, address begin, address end) {
ImplicitExceptionTable implicit_table(this); int pc_offset = begin - code_begin(); int cont_offset = implicit_table.continuation_offset(pc_offset); bool oop_map_required = false; if (cont_offset != 0) {
st->move_to(column, 6, 0); if (pc_offset == cont_offset) {
st->print("; implicit exception: deoptimizes");
oop_map_required = true;
} else {
st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
}
}
// Find an oopmap in (begin, end]. We use the odd half-closed // interval so that oop maps and scope descs which are tied to the // byte after a call are printed with the call itself. OopMaps // associated with implicit exceptions are printed with the implicit // instruction.
address base = code_begin();
ImmutableOopMapSet* oms = oop_maps(); if (oms != NULL) { for (int i = 0, imax = oms->count(); i < imax; i++) { const ImmutableOopMapPair* pair = oms->pair_at(i); const ImmutableOopMap* om = pair->get_from(oms);
address pc = base + pair->pc_offset(); if (pc >= begin) { #if INCLUDE_JVMCI bool is_implicit_deopt = implicit_table.continuation_offset(pair->pc_offset()) == (uint) pair->pc_offset(); #else bool is_implicit_deopt = false; #endif if (is_implicit_deopt ? pc == begin : pc > begin && pc <= end) {
st->move_to(column, 6, 0);
st->print("; ");
om->print_on(st);
oop_map_required = false;
}
} if (pc > end) { break;
}
}
}
assert(!oop_map_required, "missed oopmap");
Thread* thread = Thread::current();
// Print any debug info present at this pc.
ScopeDesc* sd = scope_desc_in(begin, end); if (sd != NULL) {
st->move_to(column, 6, 0); if (sd->bci() == SynchronizationEntryBCI) {
st->print(";*synchronization entry");
} elseif (sd->bci() == AfterBci) {
st->print(";* method exit (unlocked if synchronized)");
} elseif (sd->bci() == UnwindBci) {
st->print(";* unwind (locked if synchronized)");
} elseif (sd->bci() == AfterExceptionBci) {
st->print(";* unwind (unlocked if synchronized)");
} elseif (sd->bci() == UnknownBci) {
st->print(";* unknown");
} elseif (sd->bci() == InvalidFrameStateBci) {
st->print(";* invalid frame state");
} else { if (sd->method() == NULL) {
st->print("method is NULL");
} elseif (sd->method()->is_native()) {
st->print("method is native");
} else {
Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
st->print(";*%s", Bytecodes::name(bc)); switch (bc) { case Bytecodes::_invokevirtual: case Bytecodes::_invokespecial: case Bytecodes::_invokestatic: case Bytecodes::_invokeinterface:
{
Bytecode_invoke invoke(methodHandle(thread, sd->method()), sd->bci());
st->print(" "); if (invoke.name() != NULL)
invoke.name()->print_symbol_on(st); else
st->print("<UNKNOWN>"); break;
} case Bytecodes::_getfield: case Bytecodes::_putfield: case Bytecodes::_getstatic: case Bytecodes::_putstatic:
{
Bytecode_field field(methodHandle(thread, sd->method()), sd->bci());
st->print(" "); if (field.name() != NULL)
field.name()->print_symbol_on(st); else
st->print("<UNKNOWN>");
} default: break;
}
}
st->print(" {reexecute=%d rethrow=%d return_oop=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop());
}
// Print all scopes for (;sd != NULL; sd = sd->sender()) {
st->move_to(column, 6, 0);
st->print("; -"); if (sd->should_reexecute()) {
st->print(" (reexecute)");
} if (sd->method() == NULL) {
st->print("method is NULL");
} else {
sd->method()->print_short_name(st);
} int lineno = sd->method()->line_number_from_bci(sd->bci()); if (lineno != -1) {
st->print("@%d (line %d)", sd->bci(), lineno);
} else {
st->print("@%d", sd->bci());
}
st->cr();
}
}
// Print relocation information // Prevent memory leak: allocating without ResourceMark.
ResourceMark rm; constchar* str = reloc_string_for(begin, end); if (str != NULL) { if (sd != NULL) st->cr();
st->move_to(column, 6, 0);
st->print("; {%s}", str);
}
}
#endif
class DirectNativeCallWrapper: public NativeCallWrapper { private:
NativeCall* _call;
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