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third-party-mirror/openjdk/jdk25u/HEAD/./src/hotspot/share/code/nmethod.cpp
blob: e4721485e8d249059457ac15cb7ddebf1add6d10 [file]
/*
* Copyright (c) 1997, 2025, 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 "asm/assembler.inline.hpp"
#include "code/codeCache.hpp"
#include "code/compiledIC.hpp"
#include "code/dependencies.hpp"
#include "code/nativeInst.hpp"
#include "code/nmethod.inline.hpp"
#include "code/scopeDesc.hpp"
#include "compiler/abstractCompiler.hpp"
#include "compiler/compilationLog.hpp"
#include "compiler/compileBroker.hpp"
#include "compiler/compileLog.hpp"
#include "compiler/compileTask.hpp"
#include "compiler/compilerDirectives.hpp"
#include "compiler/compilerOracle.hpp"
#include "compiler/directivesParser.hpp"
#include "compiler/disassembler.hpp"
#include "compiler/oopMap.inline.hpp"
#include "gc/shared/barrierSet.hpp"
#include "gc/shared/barrierSetNMethod.hpp"
#include "gc/shared/classUnloadingContext.hpp"
#include "gc/shared/collectedHeap.hpp"
#include "interpreter/bytecode.inline.hpp"
#include "jvm.h"
#include "logging/log.hpp"
#include "logging/logStream.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/access.inline.hpp"
#include "oops/klass.inline.hpp"
#include "oops/method.inline.hpp"
#include "oops/methodData.hpp"
#include "oops/oop.inline.hpp"
#include "oops/weakHandle.inline.hpp"
#include "prims/jvmtiImpl.hpp"
#include "prims/jvmtiThreadState.hpp"
#include "prims/methodHandles.hpp"
#include "runtime/continuation.hpp"
#include "runtime/atomic.hpp"
#include "runtime/deoptimization.hpp"
#include "runtime/flags/flagSetting.hpp"
#include "runtime/frame.inline.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/jniHandles.inline.hpp"
#include "runtime/orderAccess.hpp"
#include "runtime/os.hpp"
#include "runtime/safepointVerifiers.hpp"
#include "runtime/serviceThread.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/signature.hpp"
#include "runtime/threadWXSetters.inline.hpp"
#include "runtime/vmThread.hpp"
#include "utilities/align.hpp"
#include "utilities/copy.hpp"
#include "utilities/dtrace.hpp"
#include "utilities/events.hpp"
#include "utilities/globalDefinitions.hpp"
#include "utilities/resourceHash.hpp"
#include "utilities/xmlstream.hpp"
#if INCLUDE_JVMCI
#include "jvmci/jvmciRuntime.hpp"
#endif
#ifdef DTRACE_ENABLED
// Only bother with this argument setup if dtrace is available
#define DTRACE_METHOD_UNLOAD_PROBE(method) \
{ \
Method* m = (method); \
if (m != nullptr) { \
Symbol* klass_name = m->klass_name(); \
Symbol* name = m->name(); \
Symbol* signature = m->signature(); \
HOTSPOT_COMPILED_METHOD_UNLOAD( \
(char *) klass_name->bytes(), klass_name->utf8_length(), \
(char *) name->bytes(), name->utf8_length(), \
(char *) signature->bytes(), signature->utf8_length()); \
} \
}
#else // ndef DTRACE_ENABLED
#define DTRACE_METHOD_UNLOAD_PROBE(method)
#endif
// Cast from int value to narrow type
#define CHECKED_CAST(result, T, thing) \
result = static_cast<T>(thing); \
guarantee(static_cast<int>(result) == thing, "failed: %d != %d", static_cast<int>(result), thing);
//---------------------------------------------------------------------------------
// 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 {
uint nmethod_count;
uint total_nm_size;
uint total_immut_size;
uint total_mut_size;
uint relocation_size;
uint consts_size;
uint insts_size;
uint stub_size;
uint oops_size;
uint metadata_size;
uint dependencies_size;
uint nul_chk_table_size;
uint handler_table_size;
uint scopes_pcs_size;
uint scopes_data_size;
#if INCLUDE_JVMCI
uint speculations_size;
uint jvmci_data_size;
#endif
void note_nmethod(nmethod* nm) {
nmethod_count += 1;
total_nm_size += nm->size();
total_immut_size += nm->immutable_data_size();
total_mut_size += nm->mutable_data_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(const char* name) {
if (nmethod_count == 0) return;
tty->print_cr("Statistics for %u bytecoded nmethods for %s:", nmethod_count, name);
uint total_size = total_nm_size + total_immut_size + total_mut_size;
if (total_nm_size != 0) {
tty->print_cr(" total size = %u (100%%)", total_size);
tty->print_cr(" in CodeCache = %u (%f%%)", total_nm_size, (total_nm_size * 100.0f)/total_size);
}
uint header_size = (uint)(nmethod_count * sizeof(nmethod));
if (nmethod_count != 0) {
tty->print_cr(" header = %u (%f%%)", header_size, (header_size * 100.0f)/total_nm_size);
}
if (consts_size != 0) {
tty->print_cr(" constants = %u (%f%%)", consts_size, (consts_size * 100.0f)/total_nm_size);
}
if (insts_size != 0) {
tty->print_cr(" main code = %u (%f%%)", insts_size, (insts_size * 100.0f)/total_nm_size);
}
if (stub_size != 0) {
tty->print_cr(" stub code = %u (%f%%)", stub_size, (stub_size * 100.0f)/total_nm_size);
}
if (oops_size != 0) {
tty->print_cr(" oops = %u (%f%%)", oops_size, (oops_size * 100.0f)/total_nm_size);
}
if (total_mut_size != 0) {
tty->print_cr(" mutable data = %u (%f%%)", total_mut_size, (total_mut_size * 100.0f)/total_size);
}
if (relocation_size != 0) {
tty->print_cr(" relocation = %u (%f%%)", relocation_size, (relocation_size * 100.0f)/total_mut_size);
}
if (metadata_size != 0) {
tty->print_cr(" metadata = %u (%f%%)", metadata_size, (metadata_size * 100.0f)/total_mut_size);
}
#if INCLUDE_JVMCI
if (jvmci_data_size != 0) {
tty->print_cr(" JVMCI data = %u (%f%%)", jvmci_data_size, (jvmci_data_size * 100.0f)/total_mut_size);
}
#endif
if (total_immut_size != 0) {
tty->print_cr(" immutable data = %u (%f%%)", total_immut_size, (total_immut_size * 100.0f)/total_size);
}
if (dependencies_size != 0) {
tty->print_cr(" dependencies = %u (%f%%)", dependencies_size, (dependencies_size * 100.0f)/total_immut_size);
}
if (nul_chk_table_size != 0) {
tty->print_cr(" nul chk table = %u (%f%%)", nul_chk_table_size, (nul_chk_table_size * 100.0f)/total_immut_size);
}
if (handler_table_size != 0) {
tty->print_cr(" handler table = %u (%f%%)", handler_table_size, (handler_table_size * 100.0f)/total_immut_size);
}
if (scopes_pcs_size != 0) {
tty->print_cr(" scopes pcs = %u (%f%%)", scopes_pcs_size, (scopes_pcs_size * 100.0f)/total_immut_size);
}
if (scopes_data_size != 0) {
tty->print_cr(" scopes data = %u (%f%%)", scopes_data_size, (scopes_data_size * 100.0f)/total_immut_size);
}
#if INCLUDE_JVMCI
if (speculations_size != 0) {
tty->print_cr(" speculations = %u (%f%%)", speculations_size, (speculations_size * 100.0f)/total_immut_size);
}
#endif
}
};
struct native_nmethod_stats_struct {
uint native_nmethod_count;
uint native_total_size;
uint native_relocation_size;
uint native_insts_size;
uint native_oops_size;
uint 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 %u native nmethods:", native_nmethod_count);
if (native_total_size != 0) tty->print_cr(" N. total size = %u", native_total_size);
if (native_relocation_size != 0) tty->print_cr(" N. relocation = %u", native_relocation_size);
if (native_insts_size != 0) tty->print_cr(" N. main code = %u", native_insts_size);
if (native_oops_size != 0) tty->print_cr(" N. oops = %u", native_oops_size);
if (native_metadata_size != 0) tty->print_cr(" N. metadata = %u", native_metadata_size);
}
};
struct pc_nmethod_stats_struct {
uint pc_desc_init; // number of initialization of cache (= number of caches)
uint pc_desc_queries; // queries to nmethod::find_pc_desc
uint pc_desc_approx; // number of those which have approximate true
uint pc_desc_repeats; // number of _pc_descs[0] hits
uint pc_desc_hits; // number of LRU cache hits
uint pc_desc_tests; // total number of PcDesc examinations
uint pc_desc_searches; // total number of quasi-binary search steps
uint pc_desc_adds; // number of LUR cache insertions
void print_pc_stats() {
tty->print_cr("PcDesc Statistics: %u queries, %.2f comparisons per query",
pc_desc_queries,
(double)(pc_desc_tests + pc_desc_searches)
/ pc_desc_queries);
tty->print_cr(" caches=%d queries=%u/%u, hits=%u+%u, tests=%u+%u, adds=%u",
pc_desc_init,
pc_desc_queries, pc_desc_approx,
pc_desc_repeats, pc_desc_hits,
pc_desc_tests, pc_desc_searches, pc_desc_adds);
}
};
#ifdef COMPILER1
static java_nmethod_stats_struct c1_java_nmethod_stats;
#endif
#ifdef COMPILER2
static java_nmethod_stats_struct c2_java_nmethod_stats;
#endif
#if INCLUDE_JVMCI
static java_nmethod_stats_struct jvmci_java_nmethod_stats;
#endif
static java_nmethod_stats_struct unknown_java_nmethod_stats;
static native_nmethod_stats_struct native_nmethod_stats;
static pc_nmethod_stats_struct pc_nmethod_stats;
static void note_java_nmethod(nmethod* nm) {
#ifdef COMPILER1
if (nm->is_compiled_by_c1()) {
c1_java_nmethod_stats.note_nmethod(nm);
} else
#endif
#ifdef COMPILER2
if (nm->is_compiled_by_c2()) {
c2_java_nmethod_stats.note_nmethod(nm);
} else
#endif
#if INCLUDE_JVMCI
if (nm->is_compiled_by_jvmci()) {
jvmci_java_nmethod_stats.note_nmethod(nm);
} else
#endif
{
unknown_java_nmethod_stats.note_nmethod(nm);
}
}
#endif // !PRODUCT
//---------------------------------------------------------------------------------
ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
assert(pc != nullptr, "Must be non null");
assert(exception.not_null(), "Must be non null");
assert(handler != nullptr, "Must be non null");
_count = 0;
_exception_type = exception->klass();
_next = nullptr;
_purge_list_next = nullptr;
add_address_and_handler(pc,handler);
}
address ExceptionCache::match(Handle exception, address pc) {
assert(pc != nullptr,"Must be non null");
assert(exception.not_null(),"Must be non null");
if (exception->klass() == exception_type()) {
return (test_address(pc));
}
return nullptr;
}
bool ExceptionCache::match_exception_with_space(Handle exception) {
assert(exception.not_null(),"Must be non null");
if (exception->klass() == exception_type() && count() < cache_size) {
return true;
}
return false;
}
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 nullptr;
}
bool ExceptionCache::add_address_and_handler(address addr, address handler) {
if (test_address(addr) == handler) return true;
int index = count();
if (index < cache_size) {
set_pc_at(index, addr);
set_handler_at(index, handler);
increment_count();
return true;
}
return false;
}
ExceptionCache* ExceptionCache::next() {
return Atomic::load(&_next);
}
void ExceptionCache::set_next(ExceptionCache *ec) {
Atomic::store(&_next, ec);
}
//-----------------------------------------------------------------------------
// Helper used by both find_pc_desc methods.
static inline bool 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 {
// Do not look before the sentinel
assert(pc_offset > PcDesc::lower_offset_limit, "illegal pc_offset");
return pc_offset <= pc->pc_offset() && (pc-1)->pc_offset() < pc_offset;
}
}
void PcDescCache::init_to(PcDesc* initial_pc_desc) {
NOT_PRODUCT(++pc_nmethod_stats.pc_desc_init);
// initialize the cache by filling it with benign (non-null) values
assert(initial_pc_desc != nullptr && initial_pc_desc->pc_offset() == PcDesc::lower_offset_limit,
"must start with a sentinel");
for (int i = 0; i < cache_size; i++) {
_pc_descs[i] = initial_pc_desc;
}
}
PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
// 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];
assert(res != nullptr, "PcDesc cache should be initialized already");
// Approximate only here since PcDescContainer::find_pc_desc() checked for exact case.
if (approximate && 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 nullptr;
}
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)
static int 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;
}
bool nmethod::is_method_handle_return(address return_pc) {
if (!has_method_handle_invokes()) return false;
PcDesc* pd = pc_desc_at(return_pc);
if (pd == nullptr)
return false;
return pd->is_method_handle_invoke();
}
// Returns a string version of the method state.
const char* nmethod::state() const {
int state = get_state();
switch (state) {
case not_installed:
return "not installed";
case in_use:
return "in use";
case not_entrant:
return "not_entrant";
default:
fatal("unexpected method state: %d", state);
return nullptr;
}
}
void nmethod::set_deoptimized_done() {
ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
if (_deoptimization_status != deoptimize_done) { // can't go backwards
Atomic::store(&_deoptimization_status, deoptimize_done);
}
}
ExceptionCache* nmethod::exception_cache_acquire() const {
return Atomic::load_acquire(&_exception_cache);
}
void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
assert(new_entry != nullptr,"Must be non null");
assert(new_entry->next() == nullptr, "Must be null");
for (;;) {
ExceptionCache *ec = exception_cache();
if (ec != nullptr) {
Klass* ex_klass = ec->exception_type();
if (!ex_klass->is_loader_alive()) {
// We must guarantee that entries are not inserted with new next pointer
// edges to ExceptionCache entries with dead klasses, due to bad interactions
// with concurrent ExceptionCache cleanup. Therefore, the inserts roll
// the head pointer forward to the first live ExceptionCache, so that the new
// next pointers always point at live ExceptionCaches, that are not removed due
// to concurrent ExceptionCache cleanup.
ExceptionCache* next = ec->next();
if (Atomic::cmpxchg(&_exception_cache, ec, next) == ec) {
CodeCache::release_exception_cache(ec);
}
continue;
}
ec = exception_cache();
if (ec != nullptr) {
new_entry->set_next(ec);
}
}
if (Atomic::cmpxchg(&_exception_cache, ec, new_entry) == ec) {
return;
}
}
}
void nmethod::clean_exception_cache() {
// For each nmethod, only a single thread may call this cleanup function
// at the same time, whether called in STW cleanup or concurrent cleanup.
// Note that if the GC is processing exception cache cleaning in a concurrent phase,
// then a single writer may contend with cleaning up the head pointer to the
// first ExceptionCache node that has a Klass* that is alive. That is fine,
// as long as there is no concurrent cleanup of next pointers from concurrent writers.
// And the concurrent writers do not clean up next pointers, only the head.
// Also note that concurrent readers will walk through Klass* pointers that are not
// alive. That does not cause ABA problems, because Klass* is deleted after
// a handshake with all threads, after all stale ExceptionCaches have been
// unlinked. That is also when the CodeCache::exception_cache_purge_list()
// is deleted, with all ExceptionCache entries that were cleaned concurrently.
// That similarly implies that CAS operations on ExceptionCache entries do not
// suffer from ABA problems as unlinking and deletion is separated by a global
// handshake operation.
ExceptionCache* prev = nullptr;
ExceptionCache* curr = exception_cache_acquire();
while (curr != nullptr) {
ExceptionCache* next = curr->next();
if (!curr->exception_type()->is_loader_alive()) {
if (prev == nullptr) {
// Try to clean head; this is contended by concurrent inserts, that
// both lazily clean the head, and insert entries at the head. If
// the CAS fails, the operation is restarted.
if (Atomic::cmpxchg(&_exception_cache, curr, next) != curr) {
prev = nullptr;
curr = exception_cache_acquire();
continue;
}
} else {
// It is impossible to during cleanup connect the next pointer to
// an ExceptionCache that has not been published before a safepoint
// prior to the cleanup. Therefore, release is not required.
prev->set_next(next);
}
// prev stays the same.
CodeCache::release_exception_cache(curr);
} else {
prev = curr;
}
curr = next;
}
}
// public method for accessing the exception cache
// These are the public access methods.
address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
// We never grab a lock to read the exception cache, so we may
// have false negatives. This is okay, as it can only happen during
// the first few exception lookups for a given nmethod.
ExceptionCache* ec = exception_cache_acquire();
while (ec != nullptr) {
address ret_val;
if ((ret_val = ec->match(exception,pc)) != nullptr) {
return ret_val;
}
ec = ec->next();
}
return nullptr;
}
void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
// There are potential race conditions during exception cache updates, so we
// must own the ExceptionCache_lock before doing ANY modifications. Because
// we don't lock during reads, it is possible to have several threads attempt
// to update the cache with the same data. We need to check for already inserted
// copies of the current data before adding it.
MutexLocker ml(ExceptionCache_lock);
ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
if (target_entry == nullptr || !target_entry->add_address_and_handler(pc,handler)) {
target_entry = new ExceptionCache(exception,pc,handler);
add_exception_cache_entry(target_entry);
}
}
// private method for handling exception cache
// These methods are private, and used to manipulate the exception cache
// directly.
ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
ExceptionCache* ec = exception_cache_acquire();
while (ec != nullptr) {
if (ec->match_exception_with_space(exception)) {
return ec;
}
ec = ec->next();
}
return nullptr;
}
bool nmethod::is_at_poll_return(address pc) {
RelocIterator iter(this, pc, pc+1);
while (iter.next()) {
if (iter.type() == relocInfo::poll_return_type)
return true;
}
return false;
}
bool nmethod::is_at_poll_or_poll_return(address pc) {
RelocIterator iter(this, pc, pc+1);
while (iter.next()) {
relocInfo::relocType t = iter.type();
if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
return true;
}
return false;
}
void nmethod::verify_oop_relocations() {
// Ensure sure that the code matches the current oop values
RelocIterator iter(this, nullptr, nullptr);
while (iter.next()) {
if (iter.type() == relocInfo::oop_type) {
oop_Relocation* reloc = iter.oop_reloc();
if (!reloc->oop_is_immediate()) {
reloc->verify_oop_relocation();
}
}
}
}
ScopeDesc* nmethod::scope_desc_at(address pc) {
PcDesc* pd = pc_desc_at(pc);
guarantee(pd != nullptr, "scope must be present");
return new ScopeDesc(this, pd);
}
ScopeDesc* nmethod::scope_desc_near(address pc) {
PcDesc* pd = pc_desc_near(pc);
guarantee(pd != nullptr, "scope must be present");
return new ScopeDesc(this, pd);
}
address nmethod::oops_reloc_begin() const {
// If the method is not entrant then a JMP is plastered over the
// first few bytes. If an oop in the old code was there, that oop
// should not get GC'd. Skip the first few bytes of oops on
// not-entrant methods.
if (frame_complete_offset() != CodeOffsets::frame_never_safe &&
code_begin() + frame_complete_offset() >
verified_entry_point() + NativeJump::instruction_size)
{
// If we have a frame_complete_offset after the native jump, then there
// is no point trying to look for oops before that. This is a requirement
// for being allowed to scan oops concurrently.
return code_begin() + frame_complete_offset();
}
address low_boundary = verified_entry_point();
if (!is_in_use()) {
low_boundary += NativeJump::instruction_size;
// %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
// This means that the low_boundary is going to be a little too high.
// This shouldn't matter, since oops of non-entrant methods are never used.
// In fact, why are we bothering to look at oops in a non-entrant method??
}
return low_boundary;
}
// Method that knows how to preserve outgoing arguments at call. This method must be
// called with a frame corresponding to a Java invoke
void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
if (method() == nullptr) {
return;
}
// handle the case of an anchor explicitly set in continuation code that doesn't have a callee
JavaThread* thread = reg_map->thread();
if ((thread->has_last_Java_frame() && fr.sp() == thread->last_Java_sp())
JVMTI_ONLY(|| (method()->is_continuation_enter_intrinsic() && thread->on_monitor_waited_event()))) {
return;
}
if (!method()->is_native()) {
address pc = fr.pc();
bool has_receiver, has_appendix;
Symbol* signature;
// The method attached by JIT-compilers should be used, if present.
// Bytecode can be inaccurate in such case.
Method* callee = attached_method_before_pc(pc);
if (callee != nullptr) {
has_receiver = !(callee->access_flags().is_static());
has_appendix = false;
signature = callee->signature();
} else {
SimpleScopeDesc ssd(this, pc);
Bytecode_invoke call(methodHandle(Thread::current(), ssd.method()), ssd.bci());
has_receiver = call.has_receiver();
has_appendix = call.has_appendix();
signature = call.signature();
}
fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
} else if (method()->is_continuation_enter_intrinsic()) {
// This method only calls Continuation.enter()
Symbol* signature = vmSymbols::continuationEnter_signature();
fr.oops_compiled_arguments_do(signature, false, false, reg_map, f);
}
}
Method* nmethod::attached_method(address call_instr) {
assert(code_contains(call_instr), "not part of the nmethod");
RelocIterator iter(this, call_instr, call_instr + 1);
while (iter.next()) {
if (iter.addr() == call_instr) {
switch(iter.type()) {
case relocInfo::static_call_type: return iter.static_call_reloc()->method_value();
case relocInfo::opt_virtual_call_type: return iter.opt_virtual_call_reloc()->method_value();
case relocInfo::virtual_call_type: return iter.virtual_call_reloc()->method_value();
default: break;
}
}
}
return nullptr; // not found
}
Method* nmethod::attached_method_before_pc(address pc) {
if (NativeCall::is_call_before(pc)) {
NativeCall* ncall = nativeCall_before(pc);
return attached_method(ncall->instruction_address());
}
return nullptr; // not a call
}
void nmethod::clear_inline_caches() {
assert(SafepointSynchronize::is_at_safepoint(), "clearing of IC's only allowed at safepoint");
RelocIterator iter(this);
while (iter.next()) {
iter.reloc()->clear_inline_cache();
}
}
#ifdef ASSERT
// Check class_loader is alive for this bit of metadata.
class CheckClass : public MetadataClosure {
void do_metadata(Metadata* md) {
Klass* klass = nullptr;
if (md->is_klass()) {
klass = ((Klass*)md);
} else if (md->is_method()) {
klass = ((Method*)md)->method_holder();
} else if (md->is_methodData()) {
klass = ((MethodData*)md)->method()->method_holder();
} else if (md->is_methodCounters()) {
klass = ((MethodCounters*)md)->method()->method_holder();
} else {
md->print();
ShouldNotReachHere();
}
assert(klass->is_loader_alive(), "must be alive");
}
};
#endif // ASSERT
static void clean_ic_if_metadata_is_dead(CompiledIC *ic) {
ic->clean_metadata();
}
// Clean references to unloaded nmethods at addr from this one, which is not unloaded.
template <typename CallsiteT>
static void clean_if_nmethod_is_unloaded(CallsiteT* callsite, nmethod* from,
bool clean_all) {
CodeBlob* cb = CodeCache::find_blob(callsite->destination());
if (!cb->is_nmethod()) {
return;
}
nmethod* nm = cb->as_nmethod();
if (clean_all || !nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
callsite->set_to_clean();
}
}
// Cleans caches in nmethods that point to either classes that are unloaded
// or nmethods that are unloaded.
//
// Can be called either in parallel by G1 currently or after all
// nmethods are unloaded. Return postponed=true in the parallel case for
// inline caches found that point to nmethods that are not yet visited during
// the do_unloading walk.
void nmethod::unload_nmethod_caches(bool unloading_occurred) {
ResourceMark rm;
// Exception cache only needs to be called if unloading occurred
if (unloading_occurred) {
clean_exception_cache();
}
cleanup_inline_caches_impl(unloading_occurred, false);
#ifdef ASSERT
// Check that the metadata embedded in the nmethod is alive
CheckClass check_class;
metadata_do(&check_class);
#endif
}
void nmethod::run_nmethod_entry_barrier() {
BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
if (bs_nm != nullptr) {
// We want to keep an invariant that nmethods found through iterations of a Thread's
// nmethods found in safepoints have gone through an entry barrier and are not armed.
// By calling this nmethod entry barrier, it plays along and acts
// like any other nmethod found on the stack of a thread (fewer surprises).
nmethod* nm = this;
bool alive = bs_nm->nmethod_entry_barrier(nm);
assert(alive, "should be alive");
}
}
// Only called by whitebox test
void nmethod::cleanup_inline_caches_whitebox() {
assert_locked_or_safepoint(CodeCache_lock);
CompiledICLocker ic_locker(this);
cleanup_inline_caches_impl(false /* unloading_occurred */, true /* clean_all */);
}
address* nmethod::orig_pc_addr(const frame* fr) {
return (address*) ((address)fr->unextended_sp() + orig_pc_offset());
}
// Called to clean up after class unloading for live nmethods
void nmethod::cleanup_inline_caches_impl(bool unloading_occurred, bool clean_all) {
assert(CompiledICLocker::is_safe(this), "mt unsafe call");
ResourceMark rm;
// Find all calls in an nmethod and clear the ones that point to bad nmethods.
RelocIterator iter(this, oops_reloc_begin());
bool is_in_static_stub = false;
while(iter.next()) {
switch (iter.type()) {
case relocInfo::virtual_call_type:
if (unloading_occurred) {
// If class unloading occurred we first clear ICs where the cached metadata
// is referring to an unloaded klass or method.
clean_ic_if_metadata_is_dead(CompiledIC_at(&iter));
}
clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), this, clean_all);
break;
case relocInfo::opt_virtual_call_type:
case relocInfo::static_call_type:
clean_if_nmethod_is_unloaded(CompiledDirectCall::at(iter.reloc()), this, clean_all);
break;
case relocInfo::static_stub_type: {
is_in_static_stub = true;
break;
}
case relocInfo::metadata_type: {
// Only the metadata relocations contained in static/opt virtual call stubs
// contains the Method* passed to c2i adapters. It is the only metadata
// relocation that needs to be walked, as it is the one metadata relocation
// that violates the invariant that all metadata relocations have an oop
// in the compiled method (due to deferred resolution and code patching).
// This causes dead metadata to remain in compiled methods that are not
// unloading. Unless these slippery metadata relocations of the static
// stubs are at least cleared, subsequent class redefinition operations
// will access potentially free memory, and JavaThread execution
// concurrent to class unloading may call c2i adapters with dead methods.
if (!is_in_static_stub) {
// The first metadata relocation after a static stub relocation is the
// metadata relocation of the static stub used to pass the Method* to
// c2i adapters.
continue;
}
is_in_static_stub = false;
if (is_unloading()) {
// If the nmethod itself is dying, then it may point at dead metadata.
// Nobody should follow that metadata; it is strictly unsafe.
continue;
}
metadata_Relocation* r = iter.metadata_reloc();
Metadata* md = r->metadata_value();
if (md != nullptr && md->is_method()) {
Method* method = static_cast<Method*>(md);
if (!method->method_holder()->is_loader_alive()) {
Atomic::store(r->metadata_addr(), (Method*)nullptr);
if (!r->metadata_is_immediate()) {
r->fix_metadata_relocation();
}
}
}
break;
}
default:
break;
}
}
}
address nmethod::continuation_for_implicit_exception(address pc, bool for_div0_check) {
// Exception happened outside inline-cache check code => we are inside
// an active nmethod => use cpc to determine a return address
int exception_offset = int(pc - code_begin());
int cont_offset = ImplicitExceptionTable(this).continuation_offset( exception_offset );
#ifdef ASSERT
if (cont_offset == 0) {
Thread* thread = Thread::current();
ResourceMark rm(thread);
CodeBlob* cb = CodeCache::find_blob(pc);
assert(cb != nullptr && cb == this, "");
// Keep tty output consistent. To avoid ttyLocker, we buffer in stream, and print all at once.
stringStream ss;
ss.print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
print_on(&ss);
method()->print_codes_on(&ss);
print_code_on(&ss);
print_pcs_on(&ss);
tty->print("%s", ss.as_string()); // print all at once
}
#endif
if (cont_offset == 0) {
// Let the normal error handling report the exception
return nullptr;
}
if (cont_offset == exception_offset) {
#if INCLUDE_JVMCI
Deoptimization::DeoptReason deopt_reason = for_div0_check ? Deoptimization::Reason_div0_check : Deoptimization::Reason_null_check;
JavaThread *thread = JavaThread::current();
thread->set_jvmci_implicit_exception_pc(pc);
thread->set_pending_deoptimization(Deoptimization::make_trap_request(deopt_reason,
Deoptimization::Action_reinterpret));
return (SharedRuntime::deopt_blob()->implicit_exception_uncommon_trap());
#else
ShouldNotReachHere();
#endif
}
return code_begin() + cont_offset;
}
class HasEvolDependency : public MetadataClosure {
bool _has_evol_dependency;
public:
HasEvolDependency() : _has_evol_dependency(false) {}
void do_metadata(Metadata* md) {
if (md->is_method()) {
Method* method = (Method*)md;
if (method->is_old()) {
_has_evol_dependency = true;
}
}
}
bool has_evol_dependency() const { return _has_evol_dependency; }
};
bool nmethod::has_evol_metadata() {
// Check the metadata in relocIter and CompiledIC and also deoptimize
// any nmethod that has reference to old methods.
HasEvolDependency check_evol;
metadata_do(&check_evol);
if (check_evol.has_evol_dependency() && log_is_enabled(Debug, redefine, class, nmethod)) {
ResourceMark rm;
log_debug(redefine, class, nmethod)
("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on in nmethod metadata",
_method->method_holder()->external_name(),
_method->name()->as_C_string(),
_method->signature()->as_C_string(),
compile_id());
}
return check_evol.has_evol_dependency();
}
int nmethod::total_size() const {
return
consts_size() +
insts_size() +
stub_size() +
scopes_data_size() +
scopes_pcs_size() +
handler_table_size() +
nul_chk_table_size();
}
const char* nmethod::compile_kind() const {
if (is_osr_method()) return "osr";
if (method() != nullptr && is_native_method()) {
if (method()->is_continuation_native_intrinsic()) {
return "cnt";
}
return "c2n";
}
return nullptr;
}
const char* nmethod::compiler_name() const {
return compilertype2name(_compiler_type);
}
#ifdef ASSERT
class CheckForOopsClosure : public OopClosure {
bool _found_oop = false;
public:
virtual void do_oop(oop* o) { _found_oop = true; }
virtual void do_oop(narrowOop* o) { _found_oop = true; }
bool found_oop() { return _found_oop; }
};
class CheckForMetadataClosure : public MetadataClosure {
bool _found_metadata = false;
Metadata* _ignore = nullptr;
public:
CheckForMetadataClosure(Metadata* ignore) : _ignore(ignore) {}
virtual void do_metadata(Metadata* md) { if (md != _ignore) _found_metadata = true; }
bool found_metadata() { return _found_metadata; }
};
static void assert_no_oops_or_metadata(nmethod* nm) {
if (nm == nullptr) return;
assert(nm->oop_maps() == nullptr, "expectation");
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
static int required_mutable_data_size(CodeBuffer* code_buffer,
int jvmci_data_size = 0) {
return align_up(code_buffer->total_relocation_size(), oopSize) +
align_up(code_buffer->total_metadata_size(), oopSize) +
align_up(jvmci_data_size, oopSize);
}
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 = nullptr;
int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
{
MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
CodeOffsets offsets;
offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
if (exception_handler != -1) {
offsets.set_value(CodeOffsets::Exceptions, exception_handler);
}
int mutable_data_size = required_mutable_data_size(code_buffer);
// MH intrinsics are dispatch stubs which are compatible with NonNMethod space.
// IsUnloadingBehaviour::is_unloading needs to handle them separately.
bool allow_NonNMethod_space = method->can_be_allocated_in_NonNMethod_space();
nm = new (native_nmethod_size, allow_NonNMethod_space)
nmethod(method(), compiler_none, native_nmethod_size,
compile_id, &offsets,
code_buffer, frame_size,
basic_lock_owner_sp_offset,
basic_lock_sp_offset,
oop_maps, mutable_data_size);
DEBUG_ONLY( if (allow_NonNMethod_space) assert_no_oops_or_metadata(nm); )
NOT_PRODUCT(if (nm != nullptr) native_nmethod_stats.note_native_nmethod(nm));
}
if (nm != nullptr) {
// verify nmethod
DEBUG_ONLY(nm->verify();) // might block
nm->log_new_nmethod();
}
return nm;
}
nmethod* nmethod::new_nmethod(const methodHandle& method,
int compile_id,
int entry_bci,
CodeOffsets* offsets,
int orig_pc_offset,
DebugInformationRecorder* debug_info,
Dependencies* dependencies,
CodeBuffer* code_buffer, int frame_size,
OopMapSet* oop_maps,
ExceptionHandlerTable* handler_table,
ImplicitExceptionTable* nul_chk_table,
AbstractCompiler* compiler,
CompLevel comp_level
#if INCLUDE_JVMCI
, char* speculations,
int speculations_len,
JVMCINMethodData* jvmci_data
#endif
)
{
assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
code_buffer->finalize_oop_references(method);
// create nmethod
nmethod* nm = nullptr;
int nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
int immutable_data_size =
adjust_pcs_size(debug_info->pcs_size())
+ align_up((int)dependencies->size_in_bytes(), oopSize)
+ align_up(handler_table->size_in_bytes() , oopSize)
+ align_up(nul_chk_table->size_in_bytes() , oopSize)
#if INCLUDE_JVMCI
+ align_up(speculations_len , oopSize)
#endif
+ align_up(debug_info->data_size() , oopSize);
// First, allocate space for immutable data in C heap.
address immutable_data = nullptr;
if (immutable_data_size > 0) {
immutable_data = (address)os::malloc(immutable_data_size, mtCode);
if (immutable_data == nullptr) {
vm_exit_out_of_memory(immutable_data_size, OOM_MALLOC_ERROR, "nmethod: no space for immutable data");
return nullptr;
}
}
int mutable_data_size = required_mutable_data_size(code_buffer
JVMCI_ONLY(COMMA (compiler->is_jvmci() ? jvmci_data->size() : 0)));
{
MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
nm = new (nmethod_size, comp_level)
nmethod(method(), compiler->type(), nmethod_size, immutable_data_size, mutable_data_size,
compile_id, entry_bci, immutable_data, offsets, orig_pc_offset,
debug_info, dependencies, code_buffer, frame_size, oop_maps,
handler_table, nul_chk_table, compiler, comp_level
#if INCLUDE_JVMCI
, speculations,
speculations_len,
jvmci_data
#endif
);
if (nm != nullptr) {
// 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 {
InstanceKlass* ik = deps.context_type();
if (ik == nullptr) {
continue; // ignore things like evol_method
}
// record this nmethod as dependent on this klass
ik->add_dependent_nmethod(nm);
}
}
NOT_PRODUCT(if (nm != nullptr) note_java_nmethod(nm));
}
}
// Do verification and logging outside CodeCache_lock.
if (nm != nullptr) {
// Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
DEBUG_ONLY(nm->verify();)
nm->log_new_nmethod();
}
return nm;
}
// Fill in default values for various fields
void nmethod::init_defaults(CodeBuffer *code_buffer, CodeOffsets* offsets) {
// avoid uninitialized fields, even for short time periods
_exception_cache = nullptr;
_gc_data = nullptr;
_oops_do_mark_link = nullptr;
_compiled_ic_data = nullptr;
_is_unloading_state = 0;
_state = not_installed;
_has_unsafe_access = 0;
_has_method_handle_invokes = 0;
_has_wide_vectors = 0;
_has_monitors = 0;
_has_scoped_access = 0;
_has_flushed_dependencies = 0;
_is_unlinked = 0;
_load_reported = 0; // jvmti state
_deoptimization_status = not_marked;
// SECT_CONSTS is first in code buffer so the offset should be 0.
int consts_offset = code_buffer->total_offset_of(code_buffer->consts());
assert(consts_offset == 0, "const_offset: %d", consts_offset);
_stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
CHECKED_CAST(_entry_offset, uint16_t, (offsets->value(CodeOffsets::Entry)));
CHECKED_CAST(_verified_entry_offset, uint16_t, (offsets->value(CodeOffsets::Verified_Entry)));
_skipped_instructions_size = code_buffer->total_skipped_instructions_size();
}
// Post initialization
void nmethod::post_init() {
clear_unloading_state();
finalize_relocations();
Universe::heap()->register_nmethod(this);
DEBUG_ONLY(Universe::heap()->verify_nmethod(this));
CodeCache::commit(this);
}
// 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,
int mutable_data_size)
: CodeBlob("native nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, mutable_data_size),
_deoptimization_generation(0),
_gc_epoch(CodeCache::gc_epoch()),
_method(method),
_native_receiver_sp_offset(basic_lock_owner_sp_offset),
_native_basic_lock_sp_offset(basic_lock_sp_offset)
{
{
DEBUG_ONLY(NoSafepointVerifier nsv;)
assert_locked_or_safepoint(CodeCache_lock);
init_defaults(code_buffer, offsets);
_osr_entry_point = nullptr;
_pc_desc_container = nullptr;
_entry_bci = InvocationEntryBci;
_compile_id = compile_id;
_comp_level = CompLevel_none;
_compiler_type = type;
_orig_pc_offset = 0;
_num_stack_arg_slots = 0;
if (offsets->value(CodeOffsets::Exceptions) != -1) {
// Continuation enter intrinsic
_exception_offset = code_offset() + offsets->value(CodeOffsets::Exceptions);
} else {
_exception_offset = 0;
}
// Native wrappers do not have deopt handlers. Make the values
// something that will never match a pc like the nmethod vtable entry
_deopt_handler_offset = 0;
_deopt_mh_handler_offset = 0;
_unwind_handler_offset = 0;
CHECKED_CAST(_oops_size, uint16_t, align_up(code_buffer->total_oop_size(), oopSize));
uint16_t metadata_size;
CHECKED_CAST(metadata_size, uint16_t, align_up(code_buffer->total_metadata_size(), wordSize));
JVMCI_ONLY( _metadata_size = metadata_size; )
assert(_mutable_data_size == _relocation_size + metadata_size,
"wrong mutable data size: %d != %d + %d",
_mutable_data_size, _relocation_size, metadata_size);
// native wrapper does not have read-only data but we need unique not null address
_immutable_data = blob_end();
_immutable_data_size = 0;
_nul_chk_table_offset = 0;
_handler_table_offset = 0;
_scopes_pcs_offset = 0;
_scopes_data_offset = 0;
#if INCLUDE_JVMCI
_speculations_offset = 0;
#endif
code_buffer->copy_code_and_locs_to(this);
code_buffer->copy_values_to(this);
post_init();
}
if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
ttyLocker ttyl; // keep the following output all in one block
// This output goes directly to the tty, not the compiler log.
// To enable tools to match it up with the compilation activity,
// be sure to tag this tty output with the compile ID.
if (xtty != nullptr) {
xtty->begin_head("print_native_nmethod");
xtty->method(_method);
xtty->stamp();
xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
}
// Print the header part, then print the requested information.
// This is both handled in decode2(), called via print_code() -> decode()
if (PrintNativeNMethods) {
tty->print_cr("-------------------------- Assembly (native nmethod) ---------------------------");
print_code();
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
#if defined(SUPPORT_DATA_STRUCTS)
if (AbstractDisassembler::show_structs()) {
if (oop_maps != nullptr) {
tty->print("oop maps:"); // oop_maps->print_on(tty) outputs a cr() at the beginning
oop_maps->print_on(tty);
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
}
}
#endif
} else {
print(); // print the header part only.
}
#if defined(SUPPORT_DATA_STRUCTS)
if (AbstractDisassembler::show_structs()) {
if (PrintRelocations) {
print_relocations();
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
}
}
#endif
if (xtty != nullptr) {
xtty->tail("print_native_nmethod");
}
}
}
void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
}
void* nmethod::operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw () {
// Try MethodNonProfiled and MethodProfiled.
void* return_value = CodeCache::allocate(nmethod_size, CodeBlobType::MethodNonProfiled);
if (return_value != nullptr || !allow_NonNMethod_space) return return_value;
// Try NonNMethod or give up.
return CodeCache::allocate(nmethod_size, CodeBlobType::NonNMethod);
}
// For normal JIT compiled code
nmethod::nmethod(
Method* method,
CompilerType type,
int nmethod_size,
int immutable_data_size,
int mutable_data_size,
int compile_id,
int entry_bci,
address immutable_data,
CodeOffsets* offsets,
int orig_pc_offset,
DebugInformationRecorder* debug_info,
Dependencies* dependencies,
CodeBuffer *code_buffer,
int frame_size,
OopMapSet* oop_maps,
ExceptionHandlerTable* handler_table,
ImplicitExceptionTable* nul_chk_table,
AbstractCompiler* compiler,
CompLevel comp_level
#if INCLUDE_JVMCI
, char* speculations,
int speculations_len,
JVMCINMethodData* jvmci_data
#endif
)
: CodeBlob("nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false, mutable_data_size),
_deoptimization_generation(0),
_gc_epoch(CodeCache::gc_epoch()),
_method(method),
_osr_link(nullptr)
{
assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
{
DEBUG_ONLY(NoSafepointVerifier nsv;)
assert_locked_or_safepoint(CodeCache_lock);
init_defaults(code_buffer, offsets);
_osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
_entry_bci = entry_bci;
_compile_id = compile_id;
_comp_level = comp_level;
_compiler_type = type;
_orig_pc_offset = orig_pc_offset;
_num_stack_arg_slots = entry_bci != InvocationEntryBci ? 0 : _method->constMethod()->num_stack_arg_slots();
set_ctable_begin(header_begin() + content_offset());
#if INCLUDE_JVMCI
if (compiler->is_jvmci()) {
// JVMCI might not produce any stub sections
if (offsets->value(CodeOffsets::Exceptions) != -1) {
_exception_offset = code_offset() + offsets->value(CodeOffsets::Exceptions);
} else {
_exception_offset = -1;
}
if (offsets->value(CodeOffsets::Deopt) != -1) {
_deopt_handler_offset = code_offset() + offsets->value(CodeOffsets::Deopt);
} else {
_deopt_handler_offset = -1;
}
if (offsets->value(CodeOffsets::DeoptMH) != -1) {
_deopt_mh_handler_offset = code_offset() + offsets->value(CodeOffsets::DeoptMH);
} else {
_deopt_mh_handler_offset = -1;
}
} else
#endif
{
// Exception handler and deopt handler are in the stub section
assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
_exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
_deopt_handler_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
if (offsets->value(CodeOffsets::DeoptMH) != -1) {
_deopt_mh_handler_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
} else {
_deopt_mh_handler_offset = -1;
}
}
if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
// C1 generates UnwindHandler at the end of instructions section.
// Calculate positive offset as distance between the start of stubs section
// (which is also the end of instructions section) and the start of the handler.
int unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
CHECKED_CAST(_unwind_handler_offset, int16_t, (_stub_offset - unwind_handler_offset));
} else {
_unwind_handler_offset = -1;
}
CHECKED_CAST(_oops_size, uint16_t, align_up(code_buffer->total_oop_size(), oopSize));
uint16_t metadata_size;
CHECKED_CAST(metadata_size, uint16_t, align_up(code_buffer->total_metadata_size(), wordSize));
JVMCI_ONLY( _metadata_size = metadata_size; )
int jvmci_data_size = 0 JVMCI_ONLY( + align_up(compiler->is_jvmci() ? jvmci_data->size() : 0, oopSize));
assert(_mutable_data_size == _relocation_size + metadata_size + jvmci_data_size,
"wrong mutable data size: %d != %d + %d + %d",
_mutable_data_size, _relocation_size, metadata_size, jvmci_data_size);
assert(nmethod_size == data_end() - header_begin(), "wrong nmethod size: %d != %d",
nmethod_size, (int)(code_end() - header_begin()));
_immutable_data_size = immutable_data_size;
if (immutable_data_size > 0) {
assert(immutable_data != nullptr, "required");
_immutable_data = immutable_data;
} else {
// We need unique not null address
_immutable_data = blob_end();
}
CHECKED_CAST(_nul_chk_table_offset, uint16_t, (align_up((int)dependencies->size_in_bytes(), oopSize)));
CHECKED_CAST(_handler_table_offset, uint16_t, (_nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize)));
_scopes_pcs_offset = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
_scopes_data_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
#if INCLUDE_JVMCI
_speculations_offset = _scopes_data_offset + align_up(debug_info->data_size(), oopSize);
DEBUG_ONLY( int immutable_data_end_offset = _speculations_offset + align_up(speculations_len, oopSize); )
#else
DEBUG_ONLY( int immutable_data_end_offset = _scopes_data_offset + align_up(debug_info->data_size(), oopSize); )
#endif
assert(immutable_data_end_offset <= immutable_data_size, "wrong read-only data size: %d > %d",
immutable_data_end_offset, immutable_data_size);
// Copy code and relocation info
code_buffer->copy_code_and_locs_to(this);
// Copy oops and metadata
code_buffer->copy_values_to(this);
dependencies->copy_to(this);
// Copy PcDesc and ScopeDesc data
debug_info->copy_to(this);
// Create cache after PcDesc data is copied - it will be used to initialize cache
_pc_desc_container = new PcDescContainer(scopes_pcs_begin());
#if INCLUDE_JVMCI
if (compiler->is_jvmci()) {
// Initialize the JVMCINMethodData object inlined into nm
jvmci_nmethod_data()->copy(jvmci_data);
}
#endif
// 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
post_init();
// 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());
const char* nm_kind = compile_kind();
if (nm_kind != nullptr) 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() != nullptr) {
const char* jvmci_name = jvmci_nmethod_data()->name();
if (jvmci_name != nullptr) {
log->print(" jvmci_mirror_name='");
log->text("%s", jvmci_name);
log->print("'");
}
}
#endif
}
#define LOG_OFFSET(log, name) \
if (p2i(name##_end()) - p2i(name##_begin())) \
log->print(" " XSTR(name) "_offset='%zd'" , \
p2i(name##_begin()) - p2i(this))
void nmethod::log_new_nmethod() const {
if (LogCompilation && xtty != nullptr) {
ttyLocker ttyl;
xtty->begin_elem("nmethod");
log_identity(xtty);
xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
LOG_OFFSET(xtty, relocation);
LOG_OFFSET(xtty, consts);
LOG_OFFSET(xtty, insts);
LOG_OFFSET(xtty, stub);
LOG_OFFSET(xtty, scopes_data);
LOG_OFFSET(xtty, scopes_pcs);
LOG_OFFSET(xtty, dependencies);
LOG_OFFSET(xtty, handler_table);
LOG_OFFSET(xtty, nul_chk_table);
LOG_OFFSET(xtty, oops);
LOG_OFFSET(xtty, metadata);
xtty->method(method());
xtty->stamp();
xtty->end_elem();
}
}
#undef LOG_OFFSET
// Print out more verbose output usually for a newly created nmethod.
void nmethod::print_on_with_msg(outputStream* st, const char* msg) const {
if (st != nullptr) {
ttyLocker ttyl;
if (WizardMode) {
CompileTask::print(st, this, msg, /*short_form:*/ true);
st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
} else {
CompileTask::print(st, this, msg, /*short_form:*/ false);
}
}
}
void nmethod::maybe_print_nmethod(const DirectiveSet* directive) {
bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
print_nmethod(printnmethods);
}
}
void nmethod::print_nmethod(bool printmethod) {
ttyLocker ttyl; // keep the following output all in one block
if (xtty != nullptr) {
xtty->begin_head("print_nmethod");
log_identity(xtty);
xtty->stamp();
xtty->end_head();
}
// Print the header part, then print the requested information.
// This is both handled in decode2().
if (printmethod) {
ResourceMark m;
if (is_compiled_by_c1()) {
tty->cr();
tty->print_cr("============================= C1-compiled nmethod ==============================");
}
if (is_compiled_by_jvmci()) {
tty->cr();
tty->print_cr("=========================== JVMCI-compiled nmethod =============================");
}
tty->print_cr("----------------------------------- Assembly -----------------------------------");
decode2(tty);
#if defined(SUPPORT_DATA_STRUCTS)
if (AbstractDisassembler::show_structs()) {
// Print the oops from the underlying CodeBlob as well.
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
print_oops(tty);
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
print_metadata(tty);
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
print_pcs_on(tty);
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
if (oop_maps() != nullptr) {
tty->print("oop maps:"); // oop_maps()->print_on(tty) outputs a cr() at the beginning
oop_maps()->print_on(tty);
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
}
}
#endif
} else {
print(); // print the header part only.
}
#if defined(SUPPORT_DATA_STRUCTS)
if (AbstractDisassembler::show_structs()) {
methodHandle mh(Thread::current(), _method);
if (printmethod || PrintDebugInfo || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDebugInfo)) {
print_scopes();
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
}
if (printmethod || PrintRelocations || CompilerOracle::has_option(mh, CompileCommandEnum::PrintRelocations)) {
print_relocations();
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
}
if (printmethod || PrintDependencies || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDependencies)) {
print_dependencies_on(tty);
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
}
if (printmethod || PrintExceptionHandlers) {
print_handler_table();
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
print_nul_chk_table();
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
}
if (printmethod) {
print_recorded_oops();
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
print_recorded_metadata();
tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
}
}
#endif
if (xtty != nullptr) {
xtty->tail("print_nmethod");
}
}
// Promote one word from an assembly-time handle to a live embedded oop.
inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
if (handle == nullptr ||
// 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(nullptr, nullptr, /*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();
jobject obj = *reinterpret_cast<jobject*>(dest);
initialize_immediate_oop(dest, obj);
}
// Refresh the oop-related bits of this instruction.
reloc->fix_oop_relocation();
} else if (iter.type() == relocInfo::metadata_type) {
metadata_Relocation* reloc = iter.metadata_reloc();
reloc->fix_metadata_relocation();
}
}
}
static void install_post_call_nop_displacement(nmethod* nm, address pc) {
NativePostCallNop* nop = nativePostCallNop_at((address) pc);
intptr_t cbaddr = (intptr_t) nm;
intptr_t offset = ((intptr_t) pc) - cbaddr;
int oopmap_slot = nm->oop_maps()->find_slot_for_offset(int((intptr_t) pc - (intptr_t) nm->code_begin()));
if (oopmap_slot < 0) { // this can happen at asynchronous (non-safepoint) stackwalks
log_debug(codecache)("failed to find oopmap for cb: " INTPTR_FORMAT " offset: %d", cbaddr, (int) offset);
} else if (!nop->patch(oopmap_slot, offset)) {
log_debug(codecache)("failed to encode %d %d", oopmap_slot, (int) offset);
}
}
void nmethod::finalize_relocations() {
NoSafepointVerifier nsv;
GrowableArray<NativeMovConstReg*> virtual_call_data;
// 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::virtual_call_type) {
virtual_call_Relocation* r = iter.virtual_call_reloc();
NativeMovConstReg* value = nativeMovConstReg_at(r->cached_value());
virtual_call_data.append(value);
} else 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);
}
}
if (virtual_call_data.length() > 0) {
// We allocate a block of CompiledICData per nmethod so the GC can purge this faster.
_compiled_ic_data = new CompiledICData[virtual_call_data.length()];
CompiledICData* next_data = _compiled_ic_data;
for (NativeMovConstReg* value : virtual_call_data) {
value->set_data((intptr_t)next_data);
next_data++;
}
}
}
void nmethod::make_deoptimized() {
if (!Continuations::enabled()) {
// Don't deopt this again.
set_deoptimized_done();
return;
}
assert(method() == nullptr || can_be_deoptimized(), "");
CompiledICLocker ml(this);
assert(CompiledICLocker::is_safe(this), "mt unsafe call");
// If post call nops have been already patched, we can just bail-out.
if (has_been_deoptimized()) {
return;
}
ResourceMark rm;
RelocIterator iter(this, oops_reloc_begin());
while (iter.next()) {
switch (iter.type()) {
case relocInfo::virtual_call_type: {
CompiledIC *ic = CompiledIC_at(&iter);
address pc = ic->end_of_call();
NativePostCallNop* nop = nativePostCallNop_at(pc);
if (nop != nullptr) {
nop->make_deopt();
}
assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
break;
}
case relocInfo::static_call_type:
case relocInfo::opt_virtual_call_type: {
CompiledDirectCall *csc = CompiledDirectCall::at(iter.reloc());
address pc = csc->end_of_call();
NativePostCallNop* nop = nativePostCallNop_at(pc);
//tty->print_cr(" - static pc %p", pc);
if (nop != nullptr) {
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.
set_deoptimized_done();
}
void nmethod::verify_clean_inline_caches() {
assert(CompiledICLocker::is_safe(this), "mt unsafe call");
ResourceMark rm;
RelocIterator iter(this, oops_reloc_begin());
while(iter.next()) {
switch(iter.type()) {
case relocInfo::virtual_call_type: {
CompiledIC *ic = CompiledIC_at(&iter);
CodeBlob *cb = CodeCache::find_blob(ic->destination());
assert(cb != nullptr, "destination not in CodeBlob?");
nmethod* nm = cb->as_nmethod_or_null();
if (nm != nullptr) {
// Verify that inline caches pointing to bad nmethods are clean
if (!nm->is_in_use() || nm->is_unloading()) {
assert(ic->is_clean(), "IC should be clean");
}
}
break;
}
case relocInfo::static_call_type:
case relocInfo::opt_virtual_call_type: {
CompiledDirectCall *cdc = CompiledDirectCall::at(iter.reloc());
CodeBlob *cb = CodeCache::find_blob(cdc->destination());
assert(cb != nullptr, "destination not in CodeBlob?");
nmethod* nm = cb->as_nmethod_or_null();
if (nm != nullptr) {
// Verify that inline caches pointing to bad nmethods are clean
if (!nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
assert(cdc->is_clean(), "IC should be clean");
}
}
break;
}
default:
break;
}
}
}
void nmethod::mark_as_maybe_on_stack() {
Atomic::store(&_gc_epoch, CodeCache::gc_epoch());
}
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 == nullptr) return;
MethodData* mdo = m->method_data();
if (mdo == nullptr) return;
// There is a benign race here. See comments in methodData.hpp.
mdo->inc_decompile_count();
}
bool nmethod::try_transition(signed char new_state_int) {
signed char new_state = new_state_int;
assert_lock_strong(NMethodState_lock);
signed char old_state = _state;
if (old_state >= new_state) {
// Ensure monotonicity of transitions.
return false;
}
Atomic::store(&_state, new_state);
return true;
}
void nmethod::invalidate_osr_method() {
assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
// Remove from list of active nmethods
if (method() != nullptr) {
method()->method_holder()->remove_osr_nmethod(this);
}
}
void nmethod::log_state_change(ChangeReason change_reason) const {
if (LogCompilation) {
if (xtty != nullptr) {
ttyLocker ttyl; // keep the following output all in one block
xtty->begin_elem("make_not_entrant thread='%zu' reason='%s'",
os::current_thread_id(), change_reason_to_string(change_reason));
log_identity(xtty);
xtty->stamp();
xtty->end_elem();
}
}
ResourceMark rm;
stringStream ss(NEW_RESOURCE_ARRAY(char, 256), 256);
ss.print("made not entrant: %s", change_reason_to_string(change_reason));
CompileTask::print_ul(this, ss.freeze());
if (PrintCompilation) {
print_on_with_msg(tty, ss.freeze());
}
}
void nmethod::unlink_from_method() {
if (method() != nullptr) {
method()->unlink_code(this);
}
}
// Invalidate code
bool nmethod::make_not_entrant(ChangeReason change_reason) {
// 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.
return false;
}
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.
return false;
}
{
// Enter critical section. Does not block for safepoint.
ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), 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.
return false;
}
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();
}
// Change state
bool success = try_transition(not_entrant);
assert(success, "Transition can't fail");
// Log the transition once
log_state_change(change_reason);
// Remove nmethod from method.
unlink_from_method();
} // leave critical region under NMethodState_lock
#if INCLUDE_JVMCI
// Invalidate can't occur while holding the NMethodState_lock
JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
if (nmethod_data != nullptr) {
nmethod_data->invalidate_nmethod_mirror(this);
}
#endif
#ifdef ASSERT
if (is_osr_method() && method() != nullptr) {
// 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
return true;
}
// For concurrent GCs, there must be a handshake between unlink and flush
void nmethod::unlink() {
if (is_unlinked()) {
// Already unlinked.
return;
}
flush_dependencies();
// unlink_from_method will take the NMethodState_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();
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 != nullptr) {
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.
ClassUnloadingContext::context()->register_unlinked_nmethod(this);
}
void nmethod::purge(bool unregister_nmethod) {
MutexLocker ml(CodeCache_lock, Mutex::_no_safepoint_check_flag);
// completely deallocate this method
Events::log_nmethod_flush(Thread::current(), "flushing %s nmethod " INTPTR_FORMAT, is_osr_method() ? "osr" : "", p2i(this));
LogTarget(Debug, codecache) lt;
if (lt.is_enabled()) {
ResourceMark rm;
LogStream ls(lt);
const char* method_name = method()->name()->as_C_string();
const size_t codecache_capacity = CodeCache::capacity()/1024;
const size_t codecache_free_space = CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024;
ls.print("Flushing nmethod %6d/" INTPTR_FORMAT ", level=%d, osr=%d, cold=%d, epoch=" UINT64_FORMAT ", cold_count=" UINT64_FORMAT ". "
"Cache capacity: %zuKb, free space: %zuKb. method %s (%s)",
_compile_id, p2i(this), _comp_level, is_osr_method(), is_cold(), _gc_epoch, CodeCache::cold_gc_count(),
codecache_capacity, codecache_free_space, method_name, compiler_name());
}
// 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 != nullptr) {
ExceptionCache* next = ec->next();
delete ec;
ec = next;
}
if (_pc_desc_container != nullptr) {
delete _pc_desc_container;
}
delete[] _compiled_ic_data;
if (_immutable_data != blob_end()) {
os::free(_immutable_data);
_immutable_data = blob_end(); // Valid not null address
}
if (unregister_nmethod) {
Universe::heap()->unregister_nmethod(this);
}
CodeCache::unregister_old_nmethod(this);
JVMCI_ONLY( _metadata_size = 0; )
CodeBlob::purge();
}
oop nmethod::oop_at(int index) const {
if (index == 0) {
return nullptr;
}
BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
return bs_nm->oop_load_no_keepalive(this, index);
}
oop nmethod::oop_at_phantom(int index) const {
if (index == 0) {
return nullptr;
}
BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
return bs_nm->oop_load_phantom(this, index);
}
//
// 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(true);
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 {
InstanceKlass* ik = deps.context_type();
if (ik == nullptr) {
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.
ik->clean_dependency_context();
}
}
}
}
void nmethod::post_compiled_method(CompileTask* task) {
task->mark_success();
task->set_nm_content_size(content_size());
task->set_nm_insts_size(insts_size());
task->set_nm_total_size(total_size());
// JVMTI -- compiled method notification (must be done outside lock)
post_compiled_method_load_event();
if (CompilationLog::log() != nullptr) {
CompilationLog::log()->log_nmethod(JavaThread::current(), this);
}
const DirectiveSet* directive = task->directive();
maybe_print_nmethod(directive);
}
// ------------------------------------------------------------------
// 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;
Method* m = method();
HOTSPOT_COMPILED_METHOD_LOAD(
(char *) m->klass_name()->bytes(),
m->klass_name()->utf8_length(),
(char *) m->name()->bytes(),
m->name()->utf8_length(),
(char *) m->signature()->bytes(),
m->signature()->utf8_length(),
insts_begin(), insts_size());
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 == nullptr) {
// 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);
}
}
}
void nmethod::post_compiled_method_unload() {
assert(_method != nullptr, "just checking");
DTRACE_METHOD_UNLOAD_PROBE(method());
// 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() != nullptr) {
Metadata* md = r->metadata_value();
if (md != _method) f->do_metadata(md);
}
} else if (iter.type() == relocInfo::virtual_call_type) {
// Check compiledIC holders associated with this nmethod
ResourceMark rm;
CompiledIC *ic = CompiledIC_at(&iter);
ic->metadata_do(f);
}
}
}
// Visit the metadata section
for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
if (*p == Universe::non_oop_word() || *p == nullptr) continue; // skip non-oops
Metadata* md = *p;
f->do_metadata(md);
}
// Visit metadata not embedded in the other places.
if (_method != nullptr) 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
return false;
}
if (!is_maybe_on_stack() && is_not_entrant()) {
// Not entrant nmethods that are not on any stack can just
// be removed
return true;
}
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.
return false;
}
if (!UseCodeCacheFlushing) {
// Bail out if we don't heuristically remove nmethods
return false;
}
// 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.
class IsUnloadingState: public AllStatic {
static const uint8_t _is_unloading_mask = 1;
static const uint8_t _is_unloading_shift = 0;
static const uint8_t _unloading_cycle_mask = 6;
static const uint8_t _unloading_cycle_shift = 1;
static uint8_t set_is_unloading(uint8_t state, bool value) {
state &= (uint8_t)~_is_unloading_mask;
if (value) {
state |= 1 << _is_unloading_shift;
}
assert(is_unloading(state) == value, "unexpected unloading cycle overflow");
return state;
}
static uint8_t set_unloading_cycle(uint8_t state, uint8_t value) {
state &= (uint8_t)~_unloading_cycle_mask;
state |= (uint8_t)(value << _unloading_cycle_shift);
assert(unloading_cycle(state) == value, "unexpected unloading cycle overflow");
return state;
}
public:
static bool is_unloading(uint8_t state) { return (state & _is_unloading_mask) >> _is_unloading_shift == 1; }
static uint8_t unloading_cycle(uint8_t state) { return (state & _unloading_cycle_mask) >> _unloading_cycle_shift; }
static uint8_t create(bool is_unloading, uint8_t unloading_cycle) {
uint8_t state = 0;
state = set_is_unloading(state, is_unloading);
state = set_unloading_cycle(state, unloading_cycle);
return state;
}
};
bool nmethod::is_unloading() {
uint8_t state = Atomic::load(&_is_unloading_state);
bool state_is_unloading = IsUnloadingState::is_unloading(state);
if (state_is_unloading) {
return true;
}
uint8_t state_unloading_cycle = IsUnloadingState::unloading_cycle(state);
uint8_t current_cycle = CodeCache::unloading_cycle();
if (state_unloading_cycle == current_cycle) {
return false;
}
// 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);
}
}
void nmethod::clear_unloading_state() {
uint8_t state = IsUnloadingState::create(false, CodeCache::unloading_cycle());
Atomic::store(&_is_unloading_state, 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 {
unload_nmethod_caches(unloading_occurred);
BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
if (bs_nm != nullptr) {
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() != nullptr) {
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();
BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
bs_nm->disarm(this);
// There's an assumption made that this function is not used by GCs that
// relocate objects, and therefore we don't call fix_oop_relocations.
}
nmethod* volatile nmethod::_oops_do_mark_nmethods;
void nmethod::oops_do_log_change(const char* state) {
LogTarget(Trace, gc, nmethod) lt;
if (lt.is_enabled()) {
LogStream ls(lt);
CompileTask::print(&ls, this, state, true /* short_form */);
}
}
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 == nullptr, "adding to global list as weak done must always succeed.");
return true;
}
return false;
}
bool nmethod::oops_do_try_claim_weak_request() {
assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
if ((_oops_do_mark_link == nullptr) &&
(Atomic::replace_if_null(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag)))) {
oops_do_log_change("oops_do, mark weak request");
return true;
}
return false;
}
void nmethod::oops_do_set_strong_done(nmethod* old_head) {
_oops_do_mark_link = mark_link(old_head, claim_strong_done_tag);
}
nmethod::oops_do_mark_link* nmethod::oops_do_try_claim_strong_done() {
assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, mark_link(nullptr, claim_weak_request_tag), mark_link(this, claim_strong_done_tag));
if (old_next == nullptr) {
oops_do_log_change("oops_do, mark strong done");
}
return old_next;
}
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");
return true;
}
return false;
}
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 == nullptr) {
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 nullptr;
} 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 == nullptr) {
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 == nullptr) {
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 == nullptr) {
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.
}
void nmethod::oops_do_marking_prologue() {
assert_at_safepoint();
log_trace(gc, nmethod)("oops_do_marking_prologue");
assert(_oops_do_mark_nmethods == nullptr, "must be empty");
}
void nmethod::oops_do_marking_epilogue() {
assert_at_safepoint();
nmethod* next = _oops_do_mark_nmethods;
_oops_do_mark_nmethods = nullptr;
if (next != nullptr) {
nmethod* cur;
do {
cur = next;
next = extract_nmethod(cur->_oops_do_mark_link);
cur->_oops_do_mark_link = nullptr;
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");
}
inline bool 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_offset != -1), "must have deopt mh handler");
int size = count * sizeof(PcDesc);
assert(scopes_pcs_size() >= size, "oob");
memcpy(scopes_pcs_begin(), pcs, size);
// 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");
}
void nmethod::copy_scopes_data(u_char* buffer, int size) {
assert(scopes_data_size() >= size, "oob");
memcpy(scopes_data_begin(), buffer, size);
}
#ifdef ASSERT
static PcDesc* linear_search(int pc_offset, bool approximate, PcDesc* lower, PcDesc* upper) {
PcDesc* res = nullptr;
assert(lower != nullptr && lower->pc_offset() == PcDesc::lower_offset_limit,
"must start with a sentinel");
// lower + 1 to exclude initial sentinel
for (PcDesc* p = lower + 1; 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 == nullptr) {
res = p;
} else {
res = (PcDesc*) badAddress;
}
}
}
return res;
}
#endif
#ifndef PRODUCT
// Version of method to collect statistic
PcDesc* PcDescContainer::find_pc_desc(address pc, bool approximate, address code_begin,
PcDesc* lower, PcDesc* upper) {
++pc_nmethod_stats.pc_desc_queries;
if (approximate) ++pc_nmethod_stats.pc_desc_approx;
PcDesc* desc = _pc_desc_cache.last_pc_desc();
assert(desc != nullptr, "PcDesc cache should be initialized already");
if (desc->pc_offset() == (pc - code_begin)) {
// Cached value matched
++pc_nmethod_stats.pc_desc_tests;
++pc_nmethod_stats.pc_desc_repeats;
return desc;
}
return find_pc_desc_internal(pc, approximate, code_begin, lower, upper);
}
#endif
// Finds a PcDesc with real-pc equal to "pc"
PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, address code_begin,
PcDesc* lower_incl, PcDesc* upper_incl) {
if ((pc < code_begin) ||
(pc - code_begin) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
return nullptr; // PC is wildly out of range
}
int pc_offset = (int) (pc - code_begin);
// 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 != nullptr) {
assert(res == linear_search(pc_offset, approximate, lower_incl, upper_incl), "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 = lower_incl; // this is initial sentinel
PcDesc* upper = upper_incl - 1; // exclude final sentinel
if (lower >= upper) return nullptr; // 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)
const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ DEBUG_ONLY(-1);
const int 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
if (match_desc(upper, pc_offset, approximate)) {
assert(upper == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
if (!Thread::current_in_asgct()) {
// we don't want to modify the cache if we're in ASGCT
// which is typically called in a signal handler
_pc_desc_cache.add_pc_desc(upper);
}
return upper;
} else {
assert(nullptr == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
return nullptr;
}
}
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) != nullptr) {
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) return true;
}
return false;
}
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");
}
// -----------------------------------------------------------------------------
// Verification
class VerifyOopsClosure: public OopClosure {
nmethod* _nm;
bool _ok;
public:
VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
bool ok() { return _ok; }
virtual void 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;
}
}
virtual void 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("find_nmethod 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) != nullptr, "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 == nullptr, "_oops_do_mark_link for %s should be nullptr but is " PTR_FORMAT,
nm->method()->external_name(), p2i(_oops_do_mark_link));
verify_scopes();
CompiledICLocker nm_verify(this);
VerifyMetadataClosure vmc;
metadata_do(&vmc);
}
void nmethod::verify_interrupt_point(address call_site, bool is_inline_cache) {
// Verify IC only when nmethod installation is finished.
if (!is_not_installed()) {
if (CompiledICLocker::is_safe(this)) {
if (is_inline_cache) {
CompiledIC_at(this, call_site);
} else {
CompiledDirectCall::at(call_site);
}
} else {
CompiledICLocker ml_verify(this);
if (is_inline_cache) {
CompiledIC_at(this, call_site);
} else {
CompiledDirectCall::at(call_site);
}
}
}
HandleMark hm(Thread::current());
PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
assert(pd != nullptr, "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(this);
while (iter.next()) {
address stub = nullptr;
switch (iter.type()) {
case relocInfo::virtual_call_type:
verify_interrupt_point(iter.addr(), true /* is_inline_cache */);
break;
case relocInfo::opt_virtual_call_type:
stub = iter.opt_virtual_call_reloc()->static_stub();
verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
break;
case relocInfo::static_call_type:
stub = iter.static_call_reloc()->static_stub();
verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
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 == nullptr || stub_contains(stub), "static call stub outside stub section");
}
}
// -----------------------------------------------------------------------------
// Printing operations
void nmethod::print_on_impl(outputStream* st) const {
ResourceMark rm;
st->print("Compiled method ");
if (is_compiled_by_c1()) {
st->print("(c1) ");
} else if (is_compiled_by_c2()) {
st->print("(c2) ");
} else if (is_compiled_by_jvmci()) {
st->print("(JVMCI) ");
} else {
st->print("(n/a) ");
}
print_on_with_msg(st, nullptr);
if (WizardMode) {
st->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
st->print(" for method " INTPTR_FORMAT , p2i(method()));
st->print(" { ");
st->print_cr("%s ", state());
st->print_cr("}:");
}
if (size () > 0) st->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(this),
p2i(this) + size(),
size());
if (consts_size () > 0) st->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(consts_begin()),
p2i(consts_end()),
consts_size());
if (insts_size () > 0) st->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(insts_begin()),
p2i(insts_end()),
insts_size());
if (stub_size () > 0) st->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(stub_begin()),
p2i(stub_end()),
stub_size());
if (oops_size () > 0) st->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(oops_begin()),
p2i(oops_end()),
oops_size());
if (mutable_data_size() > 0) st->print_cr(" mutable data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(mutable_data_begin()),
p2i(mutable_data_end()),
mutable_data_size());
if (relocation_size() > 0) st->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(relocation_begin()),
p2i(relocation_end()),
relocation_size());
if (metadata_size () > 0) st->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(metadata_begin()),
p2i(metadata_end()),
metadata_size());
#if INCLUDE_JVMCI
if (jvmci_data_size () > 0) st->print_cr(" JVMCI data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(jvmci_data_begin()),
p2i(jvmci_data_end()),
jvmci_data_size());
#endif
if (immutable_data_size() > 0) st->print_cr(" immutable data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(immutable_data_begin()),
p2i(immutable_data_end()),
immutable_data_size());
if (dependencies_size () > 0) st->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(dependencies_begin()),
p2i(dependencies_end()),
dependencies_size());
if (nul_chk_table_size() > 0) st->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(nul_chk_table_begin()),
p2i(nul_chk_table_end()),
nul_chk_table_size());
if (handler_table_size() > 0) st->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(handler_table_begin()),
p2i(handler_table_end()),
handler_table_size());
if (scopes_pcs_size () > 0) st->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(scopes_pcs_begin()),
p2i(scopes_pcs_end()),
scopes_pcs_size());
if (scopes_data_size () > 0) st->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(scopes_data_begin()),
p2i(scopes_data_end()),
scopes_data_size());
#if INCLUDE_JVMCI
if (speculations_size () > 0) st->print_cr(" speculations [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
p2i(speculations_begin()),
p2i(speculations_end()),
speculations_size());
#endif
}
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_on(outputStream* out) {
ResourceMark rm;
stringStream st;
st.print_cr("Dependencies:");
for (Dependencies::DepStream deps(this); deps.next(); ) {
deps.print_dependency(&st);
InstanceKlass* ctxk = deps.context_type();
if (ctxk != nullptr) {
if (ctxk->is_dependent_nmethod(this)) {
st.print_cr(" [nmethod<=klass]%s", ctxk->external_name());
}
}
deps.log_dependency(); // put it into the xml log also
}
out->print_raw(st.as_string());
}
#endif
#if defined(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((unsigned char*)p, (unsigned char*)oops_begin(), (unsigned char*)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 == nullptr) {
st->print_cr("nullptr-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((unsigned char*)p, (unsigned char*)metadata_begin(), (unsigned char*)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;
ScopeDesc* sd = scope_desc_at(p->real_pc(this));
while (sd != nullptr) {
sd->print_on(st, p); // print output ends with a newline
sd = sd->sender();
}
}
} else {
st->print_cr(" <list empty>");
}
}
#endif
#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_on(tty);
}
#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_handler_table() {
ExceptionHandlerTable(this).print(code_begin());
}
void nmethod::print_nul_chk_table() {
ImplicitExceptionTable(this).print(code_begin());
}
void nmethod::print_recorded_oop(int log_n, int i) {
void* value;
if (i == 0) {
value = nullptr;
} 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));
if (value == Universe::non_oop_word()) {
tty->print("non-oop word");
} else {
if (value == nullptr) {
tty->print("nullptr-oop");
} else {
oop_at(i)->print_value_on(tty);
}
}
tty->cr();
}
void nmethod::print_recorded_oops() {
const int n = oops_count();
const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
tty->print("Recorded oops:");
if (n > 0) {
tty->cr();
for (int i = 0; i < n; i++) {
print_recorded_oop(log_n, i);
}
} else {
tty->print_cr(" <list empty>");
}
}
void nmethod::print_recorded_metadata() {
const int n = metadata_count();
const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
tty->print("Recorded metadata:");
if (n > 0) {
tty->cr();
for (int i = 0; i < n; i++) {
Metadata* m = metadata_at(i);
tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(m));
if (m == (Metadata*)Universe::non_oop_word()) {
tty->print("non-metadata word");
} else if (m == nullptr) {
tty->print("nullptr-oop");
} else {
Metadata::print_value_on_maybe_null(tty, m);
}
tty->cr();
}
} else {
tty->print_cr(" <list empty>");
}
}
#endif
#if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
void nmethod::print_constant_pool(outputStream* st) {
//-----------------------------------
//---< Print the constant pool >---
//-----------------------------------
int consts_size = this->consts_size();
if ( consts_size > 0 ) {
unsigned char* cstart = this->consts_begin();
unsigned char* cp = cstart;
unsigned char* cend = cp + consts_size;
unsigned int bytes_per_line = 4;
unsigned int CP_alignment = 8;
unsigned int n;
st->cr();
//---< 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 = (int)((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;
#if defined(SUPPORT_ABSTRACT_ASSEMBLY) && ! defined(SUPPORT_ASSEMBLY)
const bool use_compressed_format = true;
const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
AbstractDisassembler::show_block_comment());
#else
const bool use_compressed_format = Disassembler::is_abstract();
const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
AbstractDisassembler::show_block_comment());
#endif
st->cr();
this->print_on(st);
st->cr();
#if defined(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
#if defined(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;
const int instr_maxlen = Assembler::instr_maxlen();
const uint tabspacing = 8;
unsigned char* start = this->code_begin();
unsigned char* p = this->code_begin();
unsigned char* end = this->code_end();
unsigned char* pss = p; // start of a code section (used for offsets)
if ((start == nullptr) || (end == nullptr)) {
st->print_cr("PrintAssembly not possible due to uninitialized section pointers");
return;
}
#endif
#if defined(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]");
const char* header = nullptr;
address p0 = p;
while (p < end) {
address pp = p;
while ((p < end) && (header == nullptr)) {
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 = nullptr;
} else if (header != nullptr) {
st->bol();
st->print_cr("%s", header);
header = nullptr;
}
}
//---< Close the output (Marker for post-mortem disassembler) >---
st->bol();
st->print_cr("[/MachCode]");
return;
}
#endif
#if defined(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 != nullptr)) {
const int 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)) >---
unsigned char* 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 >---
unsigned char* p0 = p;
p = Disassembler::decode_instruction_abstract(p, st, instruction_size_in_bytes, instr_maxlen);
compressed_format_idx += (int)(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
}
#if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
RelocIterator iter(this, begin, end);
bool have_one = false;
while (iter.next()) {
have_one = true;
switch (iter.type()) {
case relocInfo::none: {
// Skip it and check next
break;
}
case relocInfo::oop_type: {
// Get a non-resizable resource-allocated stringStream.
// Our callees make use of (nested) ResourceMarks.
stringStream st(NEW_RESOURCE_ARRAY(char, 1024), 1024);
oop_Relocation* r = iter.oop_reloc();
oop obj = r->oop_value();
st.print("oop(");
if (obj == nullptr) st.print("nullptr");
else obj->print_value_on(&st);
st.print(")");
return st.as_string();
}
case relocInfo::metadata_type: {
stringStream st;
metadata_Relocation* r = iter.metadata_reloc();
Metadata* obj = r->metadata_value();
st.print("metadata(");
if (obj == nullptr) st.print("nullptr");
else obj->print_value_on(&st);
st.print(")");
return st.as_string();
}
case relocInfo::runtime_call_type:
case relocInfo::runtime_call_w_cp_type: {
stringStream st;
st.print("runtime_call");
CallRelocation* r = (CallRelocation*)iter.reloc();
address dest = r->destination();
if (StubRoutines::contains(dest)) {
StubCodeDesc* desc = StubCodeDesc::desc_for(dest);
if (desc == nullptr) {
desc = StubCodeDesc::desc_for(dest + frame::pc_return_offset);
}
if (desc != nullptr) {
st.print(" Stub::%s", desc->name());
return st.as_string();
}
}
CodeBlob* cb = CodeCache::find_blob(dest);
if (cb != nullptr) {
st.print(" %s", cb->name());
} else {
ResourceMark rm;
const int buflen = 1024;
char* buf = NEW_RESOURCE_ARRAY(char, buflen);
int offset;
if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
st.print(" %s", buf);
if (offset != 0) {
st.print("+%d", offset);
}
}
}
return st.as_string();
}
case relocInfo::virtual_call_type: {
stringStream st;
st.print_raw("virtual_call");
virtual_call_Relocation* r = iter.virtual_call_reloc();
Method* m = r->method_value();
if (m != nullptr) {
assert(m->is_method(), "");
m->print_short_name(&st);
}
return st.as_string();
}
case relocInfo::opt_virtual_call_type: {
stringStream st;
st.print_raw("optimized virtual_call");
opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
Method* m = r->method_value();
if (m != nullptr) {
assert(m->is_method(), "");
m->print_short_name(&st);
}
return st.as_string();
}
case relocInfo::static_call_type: {
stringStream st;
st.print_raw("static_call");
static_call_Relocation* r = iter.static_call_reloc();
Method* m = r->method_value();
if (m != nullptr) {
assert(m->is_method(), "");
m->print_short_name(&st);
}
return st.as_string();
}
case relocInfo::static_stub_type: return "static_stub";
case relocInfo::external_word_type: return "external_word";
case relocInfo::internal_word_type: return "internal_word";
case relocInfo::section_word_type: return "section_word";
case relocInfo::poll_type: return "poll";
case relocInfo::poll_return_type: return "poll_return";
case relocInfo::trampoline_stub_type: return "trampoline_stub";
case relocInfo::entry_guard_type: return "entry_guard";
case relocInfo::post_call_nop_type: return "post_call_nop";
case relocInfo::barrier_type: {
barrier_Relocation* const reloc = iter.barrier_reloc();
stringStream st;
st.print("barrier format=%d", reloc->format());
return st.as_string();
}
case relocInfo::type_mask: return "type_bit_mask";
default: {
stringStream st;
st.print("unknown relocInfo=%d", (int) iter.type());
return st.as_string();
}
}
}
return have_one ? "other" : nullptr;
}
// Return the last scope in (begin..end]
ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
PcDesc* p = pc_desc_near(begin+1);
if (p != nullptr && p->real_pc(this) <= end) {
return new ScopeDesc(this, p);
}
return nullptr;
}
const char* nmethod::nmethod_section_label(address pos) const {
const char* label = nullptr;
if (pos == code_begin()) label = "[Instructions begin]";
if (pos == entry_point()) label = "[Entry Point]";
if (pos == verified_entry_point()) label = "[Verified Entry Point]";
if (has_method_handle_invokes() && (pos == deopt_mh_handler_begin())) label = "[Deopt MH Handler Code]";
if (pos == consts_begin() && pos != insts_begin()) label = "[Constants]";
// Check stub_code before checking exception_handler or deopt_handler.
if (pos == this->stub_begin()) label = "[Stub Code]";
if (JVMCI_ONLY(_exception_offset >= 0 &&) pos == exception_begin()) label = "[Exception Handler]";
if (JVMCI_ONLY(_deopt_handler_offset != -1 &&) pos == deopt_handler_begin()) label = "[Deopt Handler Code]";
return label;
}
void nmethod::print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels) const {
if (print_section_labels) {
const char* label = nmethod_section_label(block_begin);
if (label != nullptr) {
stream->bol();
stream->print_cr("%s", label);
}
}
if (block_begin == entry_point()) {
Method* m = method();
if (m != nullptr) {
stream->print(" # ");
m->print_value_on(stream);
stream->cr();
}
if (m != nullptr && !is_osr_method()) {
ResourceMark rm;
int sizeargs = m->size_of_parameters();
BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
{
int sig_index = 0;
if (!m->is_static())
sig_bt[sig_index++] = T_OBJECT; // 'this'
for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
BasicType t = ss.type();
sig_bt[sig_index++] = t;
if (type2size[t] == 2) {
sig_bt[sig_index++] = T_VOID;
} else {
assert(type2size[t] == 1, "size is 1 or 2");
}
}
assert(sig_index == sizeargs, "");
}
const char* spname = "sp"; // make arch-specific?
SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs);
int stack_slot_offset = this->frame_size() * wordSize;
int tab1 = 14, tab2 = 24;
int sig_index = 0;
int arg_index = (m->is_static() ? 0 : -1);
bool did_old_sp = false;
for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
bool at_this = (arg_index == -1);
bool at_old_sp = false;
BasicType t = (at_this ? T_OBJECT : ss.type());
assert(t == sig_bt[sig_index], "sigs in sync");
if (at_this)
stream->print(" # this: ");
else
stream->print(" # parm%d: ", arg_index);
stream->move_to(tab1);
VMReg fst = regs[sig_index].first();
VMReg snd = regs[sig_index].second();
if (fst->is_reg()) {
stream->print("%s", fst->name());
if (snd->is_valid()) {
stream->print(":%s", snd->name());
}
} else if (fst->is_stack()) {
int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
if (offset == stack_slot_offset) at_old_sp = true;
stream->print("[%s+0x%x]", spname, offset);
} else {
stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
}
stream->print(" ");
stream->move_to(tab2);
stream->print("= ");
if (at_this) {
m->method_holder()->print_value_on(stream);
} else {
bool did_name = false;
if (!at_this && ss.is_reference()) {
Symbol* name = ss.as_symbol();
name->print_value_on(stream);
did_name = true;
}
if (!did_name)
stream->print("%s", type2name(t));
}
if (at_old_sp) {
stream->print(" (%s of caller)", spname);
did_old_sp = true;
}
stream->cr();
sig_index += type2size[t];
arg_index += 1;
if (!at_this) ss.next();
}
if (!did_old_sp) {
stream->print(" # ");
stream->move_to(tab1);
stream->print("[%s+0x%x]", spname, stack_slot_offset);
stream->print(" (%s of caller)", spname);
stream->cr();
}
}
}
}
// Returns whether this nmethod has code comments.
bool nmethod::has_code_comment(address begin, address end) {
// scopes?
ScopeDesc* sd = scope_desc_in(begin, end);
if (sd != nullptr) return true;
// relocations?
const char* str = reloc_string_for(begin, end);
if (str != nullptr) return true;
// implicit exceptions?
int cont_offset = ImplicitExceptionTable(this).continuation_offset((uint)(begin - code_begin()));
if (cont_offset != 0) return true;
return false;
}
void nmethod::print_code_comment_on(outputStream* st, int column, address begin, address end) {
ImplicitExceptionTable implicit_table(this);
int pc_offset = (int)(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 != nullptr) {
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 != nullptr) {
st->move_to(column, 6, 0);
if (sd->bci() == SynchronizationEntryBCI) {
st->print(";*synchronization entry");
} else if (sd->bci() == AfterBci) {
st->print(";* method exit (unlocked if synchronized)");
} else if (sd->bci() == UnwindBci) {
st->print(";* unwind (locked if synchronized)");
} else if (sd->bci() == AfterExceptionBci) {
st->print(";* unwind (unlocked if synchronized)");
} else if (sd->bci() == UnknownBci) {
st->print(";* unknown");
} else if (sd->bci() == InvalidFrameStateBci) {
st->print(";* invalid frame state");
} else {
if (sd->method() == nullptr) {
st->print("method is nullptr");
} else if (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() != nullptr)
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() != nullptr)
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 != nullptr; sd = sd->sender()) {
st->move_to(column, 6, 0);
st->print("; -");
if (sd->should_reexecute()) {
st->print(" (reexecute)");
}
if (sd->method() == nullptr) {
st->print("method is nullptr");
} 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;
const char* str = reloc_string_for(begin, end);
if (str != nullptr) {
if (sd != nullptr) st->cr();
st->move_to(column, 6, 0);
st->print("; {%s}", str);
}
}
#endif
address nmethod::call_instruction_address(address pc) const {
if (NativeCall::is_call_before(pc)) {
NativeCall *ncall = nativeCall_before(pc);
return ncall->instruction_address();
}
return nullptr;
}
void nmethod::print_value_on_impl(outputStream* st) const {
st->print_cr("nmethod");
#if defined(SUPPORT_DATA_STRUCTS)
print_on_with_msg(st, nullptr);
#endif
}
#ifndef PRODUCT
void nmethod::print_calls(outputStream* st) {
RelocIterator iter(this);
while (iter.next()) {
switch (iter.type()) {
case relocInfo::virtual_call_type: {
CompiledICLocker ml_verify(this);
CompiledIC_at(&iter)->print();
break;
}
case relocInfo::static_call_type:
case relocInfo::opt_virtual_call_type:
st->print_cr("Direct call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
CompiledDirectCall::at(iter.reloc())->print();
break;
default:
break;
}
}
}
void nmethod::print_statistics() {
ttyLocker ttyl;
if (xtty != nullptr) xtty->head("statistics type='nmethod'");
native_nmethod_stats.print_native_nmethod_stats();
#ifdef COMPILER1
c1_java_nmethod_stats.print_nmethod_stats("C1");
#endif
#ifdef COMPILER2
c2_java_nmethod_stats.print_nmethod_stats("C2");
#endif
#if INCLUDE_JVMCI
jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
#endif
unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
DebugInformationRecorder::print_statistics();
pc_nmethod_stats.print_pc_stats();
Dependencies::print_statistics();
ExternalsRecorder::print_statistics();
if (xtty != nullptr) xtty->tail("statistics");
}
#endif // !PRODUCT
#if INCLUDE_JVMCI
void nmethod::update_speculation(JavaThread* thread) {
jlong speculation = thread->pending_failed_speculation();
if (speculation != 0) {
guarantee(jvmci_nmethod_data() != nullptr, "failed speculation in nmethod without failed speculation list");
jvmci_nmethod_data()->add_failed_speculation(this, speculation);
thread->set_pending_failed_speculation(0);
}
}
const char* nmethod::jvmci_name() {
if (jvmci_nmethod_data() != nullptr) {
return jvmci_nmethod_data()->name();
}
return nullptr;
}
#endif