JDK14/Java14源码在线阅读
/*
* Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "asm/codeBuffer.hpp"
#include "c1/c1_CodeStubs.hpp"
#include "c1/c1_Defs.hpp"
#include "c1/c1_FrameMap.hpp"
#include "c1/c1_LIRAssembler.hpp"
#include "c1/c1_MacroAssembler.hpp"
#include "c1/c1_Runtime1.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/vmSymbols.hpp"
#include "code/codeBlob.hpp"
#include "code/compiledIC.hpp"
#include "code/pcDesc.hpp"
#include "code/scopeDesc.hpp"
#include "code/vtableStubs.hpp"
#include "compiler/compilationPolicy.hpp"
#include "compiler/disassembler.hpp"
#include "gc/shared/barrierSet.hpp"
#include "gc/shared/c1/barrierSetC1.hpp"
#include "gc/shared/collectedHeap.hpp"
#include "interpreter/bytecode.hpp"
#include "interpreter/interpreter.hpp"
#include "jfr/support/jfrIntrinsics.hpp"
#include "logging/log.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/oopFactory.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/access.inline.hpp"
#include "oops/objArrayOop.inline.hpp"
#include "oops/objArrayKlass.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/atomic.hpp"
#include "runtime/biasedLocking.hpp"
#include "runtime/fieldDescriptor.inline.hpp"
#include "runtime/frame.inline.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/threadCritical.hpp"
#include "runtime/vframe.inline.hpp"
#include "runtime/vframeArray.hpp"
#include "runtime/vm_version.hpp"
#include "utilities/copy.hpp"
#include "utilities/events.hpp"
// Implementation of StubAssembler
StubAssembler::StubAssembler(CodeBuffer* code, const char * name, int stub_id) : C1_MacroAssembler(code) {
_name = name;
_must_gc_arguments = false;
_frame_size = no_frame_size;
_num_rt_args = 0;
_stub_id = stub_id;
}
void StubAssembler::set_info(const char* name, bool must_gc_arguments) {
_name = name;
_must_gc_arguments = must_gc_arguments;
}
void StubAssembler::set_frame_size(int size) {
if (_frame_size == no_frame_size) {
_frame_size = size;
}
assert(_frame_size == size, "can't change the frame size");
}
void StubAssembler::set_num_rt_args(int args) {
if (_num_rt_args == 0) {
_num_rt_args = args;
}
assert(_num_rt_args == args, "can't change the number of args");
}
// Implementation of Runtime1
CodeBlob* Runtime1::_blobs[Runtime1::number_of_ids];
const char *Runtime1::_blob_names[] = {
RUNTIME1_STUBS(STUB_NAME, LAST_STUB_NAME)
};
#ifndef PRODUCT
// statistics
int Runtime1::_generic_arraycopy_cnt = 0;
int Runtime1::_generic_arraycopystub_cnt = 0;
int Runtime1::_arraycopy_slowcase_cnt = 0;
int Runtime1::_arraycopy_checkcast_cnt = 0;
int Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
int Runtime1::_new_type_array_slowcase_cnt = 0;
int Runtime1::_new_object_array_slowcase_cnt = 0;
int Runtime1::_new_instance_slowcase_cnt = 0;
int Runtime1::_new_multi_array_slowcase_cnt = 0;
int Runtime1::_monitorenter_slowcase_cnt = 0;
int Runtime1::_monitorexit_slowcase_cnt = 0;
int Runtime1::_patch_code_slowcase_cnt = 0;
int Runtime1::_throw_range_check_exception_count = 0;
int Runtime1::_throw_index_exception_count = 0;
int Runtime1::_throw_div0_exception_count = 0;
int Runtime1::_throw_null_pointer_exception_count = 0;
int Runtime1::_throw_class_cast_exception_count = 0;
int Runtime1::_throw_incompatible_class_change_error_count = 0;
int Runtime1::_throw_array_store_exception_count = 0;
int Runtime1::_throw_count = 0;
static int _byte_arraycopy_stub_cnt = 0;
static int _short_arraycopy_stub_cnt = 0;
static int _int_arraycopy_stub_cnt = 0;
static int _long_arraycopy_stub_cnt = 0;
static int _oop_arraycopy_stub_cnt = 0;
address Runtime1::arraycopy_count_address(BasicType type) {
switch (type) {
case T_BOOLEAN:
case T_BYTE: return (address)&_byte_arraycopy_stub_cnt;
case T_CHAR:
case T_SHORT: return (address)&_short_arraycopy_stub_cnt;
case T_FLOAT:
case T_INT: return (address)&_int_arraycopy_stub_cnt;
case T_DOUBLE:
case T_LONG: return (address)&_long_arraycopy_stub_cnt;
case T_ARRAY:
case T_OBJECT: return (address)&_oop_arraycopy_stub_cnt;
default:
ShouldNotReachHere();
return NULL;
}
}
#endif
// Simple helper to see if the caller of a runtime stub which
// entered the VM has been deoptimized
static bool caller_is_deopted() {
JavaThread* thread = JavaThread::current();
RegisterMap reg_map(thread, false);
frame runtime_frame = thread->last_frame();
frame caller_frame = runtime_frame.sender(®_map);
assert(caller_frame.is_compiled_frame(), "must be compiled");
return caller_frame.is_deoptimized_frame();
}
// Stress deoptimization
static void deopt_caller() {
if ( !caller_is_deopted()) {
JavaThread* thread = JavaThread::current();
RegisterMap reg_map(thread, false);
frame runtime_frame = thread->last_frame();
frame caller_frame = runtime_frame.sender(®_map);
Deoptimization::deoptimize_frame(thread, caller_frame.id());
assert(caller_is_deopted(), "Must be deoptimized");
}
}
class StubIDStubAssemblerCodeGenClosure: public StubAssemblerCodeGenClosure {
private:
Runtime1::StubID _id;
public:
StubIDStubAssemblerCodeGenClosure(Runtime1::StubID id) : _id(id) {}
virtual OopMapSet* generate_code(StubAssembler* sasm) {
return Runtime1::generate_code_for(_id, sasm);
}
};
CodeBlob* Runtime1::generate_blob(BufferBlob* buffer_blob, int stub_id, const char* name, bool expect_oop_map, StubAssemblerCodeGenClosure* cl) {
ResourceMark rm;
// create code buffer for code storage
CodeBuffer code(buffer_blob);
OopMapSet* oop_maps;
int frame_size;
bool must_gc_arguments;
Compilation::setup_code_buffer(&code, 0);
// create assembler for code generation
StubAssembler* sasm = new StubAssembler(&code, name, stub_id);
// generate code for runtime stub
oop_maps = cl->generate_code(sasm);
assert(oop_maps == NULL || sasm->frame_size() != no_frame_size,
"if stub has an oop map it must have a valid frame size");
assert(!expect_oop_map || oop_maps != NULL, "must have an oopmap");
// align so printing shows nop's instead of random code at the end (SimpleStubs are aligned)
sasm->align(BytesPerWord);
// make sure all code is in code buffer
sasm->flush();
frame_size = sasm->frame_size();
must_gc_arguments = sasm->must_gc_arguments();
// create blob - distinguish a few special cases
CodeBlob* blob = RuntimeStub::new_runtime_stub(name,
&code,
CodeOffsets::frame_never_safe,
frame_size,
oop_maps,
must_gc_arguments);
assert(blob != NULL, "blob must exist");
return blob;
}
void Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubID id) {
assert(0 <= id && id < number_of_ids, "illegal stub id");
bool expect_oop_map = true;
#ifdef ASSERT
// Make sure that stubs that need oopmaps have them
switch (id) {
// These stubs don't need to have an oopmap
case dtrace_object_alloc_id:
case slow_subtype_check_id:
case fpu2long_stub_id:
case unwind_exception_id:
case counter_overflow_id:
#if defined(SPARC) || defined(PPC32)
case handle_exception_nofpu_id: // Unused on sparc
#endif
expect_oop_map = false;
break;
default:
break;
}
#endif
StubIDStubAssemblerCodeGenClosure cl(id);
CodeBlob* blob = generate_blob(buffer_blob, id, name_for(id), expect_oop_map, &cl);
// install blob
_blobs[id] = blob;
}
void Runtime1::initialize(BufferBlob* blob) {
// platform-dependent initialization
initialize_pd();
// generate stubs
for (int id = 0; id < number_of_ids; id++) generate_blob_for(blob, (StubID)id);
// printing
#ifndef PRODUCT
if (PrintSimpleStubs) {
ResourceMark rm;
for (int id = 0; id < number_of_ids; id++) {
_blobs[id]->print();
if (_blobs[id]->oop_maps() != NULL) {
_blobs[id]->oop_maps()->print();
}
}
}
#endif
BarrierSetC1* bs = BarrierSet::barrier_set()->barrier_set_c1();
bs->generate_c1_runtime_stubs(blob);
}
CodeBlob* Runtime1::blob_for(StubID id) {
assert(0 <= id && id < number_of_ids, "illegal stub id");
return _blobs[id];
}
const char* Runtime1::name_for(StubID id) {
assert(0 <= id && id < number_of_ids, "illegal stub id");
return _blob_names[id];
}
const char* Runtime1::name_for_address(address entry) {
for (int id = 0; id < number_of_ids; id++) {
if (entry == entry_for((StubID)id)) return name_for((StubID)id);
}
BarrierSetC1* bsc1 = BarrierSet::barrier_set()->barrier_set_c1();
const char* name = bsc1->rtcall_name_for_address(entry);
if (name != NULL) {
return name;
}
#define FUNCTION_CASE(a, f) \
if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f)) return #f
FUNCTION_CASE(entry, os::javaTimeMillis);
FUNCTION_CASE(entry, os::javaTimeNanos);
FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
FUNCTION_CASE(entry, SharedRuntime::d2f);
FUNCTION_CASE(entry, SharedRuntime::d2i);
FUNCTION_CASE(entry, SharedRuntime::d2l);
FUNCTION_CASE(entry, SharedRuntime::dcos);
FUNCTION_CASE(entry, SharedRuntime::dexp);
FUNCTION_CASE(entry, SharedRuntime::dlog);
FUNCTION_CASE(entry, SharedRuntime::dlog10);
FUNCTION_CASE(entry, SharedRuntime::dpow);
FUNCTION_CASE(entry, SharedRuntime::drem);
FUNCTION_CASE(entry, SharedRuntime::dsin);
FUNCTION_CASE(entry, SharedRuntime::dtan);
FUNCTION_CASE(entry, SharedRuntime::f2i);
FUNCTION_CASE(entry, SharedRuntime::f2l);
FUNCTION_CASE(entry, SharedRuntime::frem);
FUNCTION_CASE(entry, SharedRuntime::l2d);
FUNCTION_CASE(entry, SharedRuntime::l2f);
FUNCTION_CASE(entry, SharedRuntime::ldiv);
FUNCTION_CASE(entry, SharedRuntime::lmul);
FUNCTION_CASE(entry, SharedRuntime::lrem);
FUNCTION_CASE(entry, SharedRuntime::lrem);
FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
FUNCTION_CASE(entry, is_instance_of);
FUNCTION_CASE(entry, trace_block_entry);
#ifdef JFR_HAVE_INTRINSICS
FUNCTION_CASE(entry, JFR_TIME_FUNCTION);
#endif
FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32());
FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32C());
FUNCTION_CASE(entry, StubRoutines::vectorizedMismatch());
FUNCTION_CASE(entry, StubRoutines::dexp());
FUNCTION_CASE(entry, StubRoutines::dlog());
FUNCTION_CASE(entry, StubRoutines::dlog10());
FUNCTION_CASE(entry, StubRoutines::dpow());
FUNCTION_CASE(entry, StubRoutines::dsin());
FUNCTION_CASE(entry, StubRoutines::dcos());
FUNCTION_CASE(entry, StubRoutines::dtan());
#undef FUNCTION_CASE
// Soft float adds more runtime names.
return pd_name_for_address(entry);
}
JRT_ENTRY(void, Runtime1::new_instance(JavaThread* thread, Klass* klass))
NOT_PRODUCT(_new_instance_slowcase_cnt++;)
assert(klass->is_klass(), "not a class");
Handle holder(THREAD, klass->klass_holder()); // keep the klass alive
InstanceKlass* h = InstanceKlass::cast(klass);
h->check_valid_for_instantiation(true, CHECK);
// make sure klass is initialized
h->initialize(CHECK);
// allocate instance and return via TLS
oop obj = h->allocate_instance(CHECK);
thread->set_vm_result(obj);
JRT_END
JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* thread, Klass* klass, jint length))
NOT_PRODUCT(_new_type_array_slowcase_cnt++;)
// Note: no handle for klass needed since they are not used
// anymore after new_typeArray() and no GC can happen before.
// (This may have to change if this code changes!)
assert(klass->is_klass(), "not a class");
BasicType elt_type = TypeArrayKlass::cast(klass)->element_type();
oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
thread->set_vm_result(obj);
// This is pretty rare but this runtime patch is stressful to deoptimization
// if we deoptimize here so force a deopt to stress the path.
if (DeoptimizeALot) {
deopt_caller();
}
JRT_END
JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* thread, Klass* array_klass, jint length))
NOT_PRODUCT(_new_object_array_slowcase_cnt++;)
// Note: no handle for klass needed since they are not used
// anymore after new_objArray() and no GC can happen before.
// (This may have to change if this code changes!)
assert(array_klass->is_klass(), "not a class");
Handle holder(THREAD, array_klass->klass_holder()); // keep the klass alive
Klass* elem_klass = ObjArrayKlass::cast(array_klass)->element_klass();
objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
thread->set_vm_result(obj);
// This is pretty rare but this runtime patch is stressful to deoptimization
// if we deoptimize here so force a deopt to stress the path.
if (DeoptimizeALot) {
deopt_caller();
}
JRT_END
JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* thread, Klass* klass, int rank, jint* dims))
NOT_PRODUCT(_new_multi_array_slowcase_cnt++;)
assert(klass->is_klass(), "not a class");
assert(rank >= 1, "rank must be nonzero");
Handle holder(THREAD, klass->klass_holder()); // keep the klass alive
oop obj = ArrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
thread->set_vm_result(obj);
JRT_END
JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* thread, StubID id))
tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", id);
JRT_END
JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* thread, oopDesc* obj))
ResourceMark rm(thread);
const char* klass_name = obj->klass()->external_name();
SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayStoreException(), klass_name);
JRT_END
// counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
// associated with the top activation record. The inlinee (that is possibly included in the enclosing
// method) method oop is passed as an argument. In order to do that it is embedded in the code as
// a constant.
static nmethod* counter_overflow_helper(JavaThread* THREAD, int branch_bci, Method* m) {
nmethod* osr_nm = NULL;
methodHandle method(THREAD, m);
RegisterMap map(THREAD, false);
frame fr = THREAD->last_frame().sender(&map);
nmethod* nm = (nmethod*) fr.cb();
assert(nm!= NULL && nm->is_nmethod(), "Sanity check");
methodHandle enclosing_method(THREAD, nm->method());
CompLevel level = (CompLevel)nm->comp_level();
int bci = InvocationEntryBci;
if (branch_bci != InvocationEntryBci) {
// Compute destination bci
address pc = method()->code_base() + branch_bci;
Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
int offset = 0;
switch (branch) {
case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
case Bytecodes::_if_icmple: case Bytecodes::_ifle:
case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
offset = (int16_t)Bytes::get_Java_u2(pc + 1);
break;
case Bytecodes::_goto_w:
offset = Bytes::get_Java_u4(pc + 1);
break;
default: ;
}
bci = branch_bci + offset;
}
assert(!HAS_PENDING_EXCEPTION, "Should not have any exceptions pending");
osr_nm = CompilationPolicy::policy()->event(enclosing_method, method, branch_bci, bci, level, nm, THREAD);
assert(!HAS_PENDING_EXCEPTION, "Event handler should not throw any exceptions");
return osr_nm;
}
JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* thread, int bci, Method* method))
nmethod* osr_nm;
JRT_BLOCK
osr_nm = counter_overflow_helper(thread, bci, method);
if (osr_nm != NULL) {
RegisterMap map(thread, false);
frame fr = thread->last_frame().sender(&map);
Deoptimization::deoptimize_frame(thread, fr.id());
}
JRT_BLOCK_END
return NULL;
JRT_END
extern void vm_exit(int code);
// Enter this method from compiled code handler below. This is where we transition
// to VM mode. This is done as a helper routine so that the method called directly
// from compiled code does not have to transition to VM. This allows the entry
// method to see if the nmethod that we have just looked up a handler for has
// been deoptimized while we were in the vm. This simplifies the assembly code
// cpu directories.
//
// We are entering here from exception stub (via the entry method below)
// If there is a compiled exception handler in this method, we will continue there;
// otherwise we will unwind the stack and continue at the caller of top frame method
// Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
// control the area where we can allow a safepoint. After we exit the safepoint area we can
// check to see if the handler we are going to return is now in a nmethod that has
// been deoptimized. If that is the case we return the deopt blob
// unpack_with_exception entry instead. This makes life for the exception blob easier
// because making that same check and diverting is painful from assembly language.
JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* thread, oopDesc* ex, address pc, nmethod*& nm))
// Reset method handle flag.
thread->set_is_method_handle_return(false);
Handle exception(thread, ex);
nm = CodeCache::find_nmethod(pc);
assert(nm != NULL, "this is not an nmethod");
// Adjust the pc as needed/
if (nm->is_deopt_pc(pc)) {
RegisterMap map(thread, false);
frame exception_frame = thread->last_frame().sender(&map);
// if the frame isn't deopted then pc must not correspond to the caller of last_frame
assert(exception_frame.is_deoptimized_frame(), "must be deopted");
pc = exception_frame.pc();
}
#ifdef ASSERT
assert(exception.not_null(), "NULL exceptions should be handled by throw_exception");
// Check that exception is a subclass of Throwable, otherwise we have a VerifyError
if (!(exception->is_a(SystemDictionary::Throwable_klass()))) {
if (ExitVMOnVerifyError) vm_exit(-1);
ShouldNotReachHere();
}
#endif
// Check the stack guard pages and reenable them if necessary and there is
// enough space on the stack to do so. Use fast exceptions only if the guard
// pages are enabled.
bool guard_pages_enabled = thread->stack_guards_enabled();
if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
if (JvmtiExport::can_post_on_exceptions()) {
// To ensure correct notification of exception catches and throws
// we have to deoptimize here. If we attempted to notify the
// catches and throws during this exception lookup it's possible
// we could deoptimize on the way out of the VM and end back in
// the interpreter at the throw site. This would result in double
// notifications since the interpreter would also notify about
// these same catches and throws as it unwound the frame.
RegisterMap reg_map(thread);
frame stub_frame = thread->last_frame();
frame caller_frame = stub_frame.sender(®_map);
// We don't really want to deoptimize the nmethod itself since we
// can actually continue in the exception handler ourselves but I
// don't see an easy way to have the desired effect.
Deoptimization::deoptimize_frame(thread, caller_frame.id());
assert(caller_is_deopted(), "Must be deoptimized");
return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
}
// ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
if (guard_pages_enabled) {
address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
if (fast_continuation != NULL) {
// Set flag if return address is a method handle call site.
thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
return fast_continuation;
}
}
// If the stack guard pages are enabled, check whether there is a handler in
// the current method. Otherwise (guard pages disabled), force an unwind and
// skip the exception cache update (i.e., just leave continuation==NULL).
address continuation = NULL;
if (guard_pages_enabled) {
// New exception handling mechanism can support inlined methods
// with exception handlers since the mappings are from PC to PC
// debugging support
// tracing
if (log_is_enabled(Info, exceptions)) {
ResourceMark rm;
stringStream tempst;
assert(nm->method() != NULL, "Unexpected NULL method()");
tempst.print("compiled method <%s>\n"
" at PC" INTPTR_FORMAT " for thread " INTPTR_FORMAT,
nm->method()->print_value_string(), p2i(pc), p2i(thread));
Exceptions::log_exception(exception, tempst.as_string());
}
// for AbortVMOnException flag
Exceptions::debug_check_abort(exception);
// Clear out the exception oop and pc since looking up an
// exception handler can cause class loading, which might throw an
// exception and those fields are expected to be clear during
// normal bytecode execution.
thread->clear_exception_oop_and_pc();
bool recursive_exception = false;
continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false, recursive_exception);
// If an exception was thrown during exception dispatch, the exception oop may have changed
thread->set_exception_oop(exception());
thread->set_exception_pc(pc);
// the exception cache is used only by non-implicit exceptions
// Update the exception cache only when there didn't happen
// another exception during the computation of the compiled
// exception handler. Checking for exception oop equality is not
// sufficient because some exceptions are pre-allocated and reused.
if (continuation != NULL && !recursive_exception) {
nm->add_handler_for_exception_and_pc(exception, pc, continuation);
}
}
thread->set_vm_result(exception());
// Set flag if return address is a method handle call site.
thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
if (log_is_enabled(Info, exceptions)) {
ResourceMark rm;
log_info(exceptions)("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT
" for exception thrown at PC " PTR_FORMAT,
p2i(thread), p2i(continuation), p2i(pc));
}
return continuation;
JRT_END
// Enter this method from compiled code only if there is a Java exception handler
// in the method handling the exception.
// We are entering here from exception stub. We don't do a normal VM transition here.
// We do it in a helper. This is so we can check to see if the nmethod we have just
// searched for an exception handler has been deoptimized in the meantime.
address Runtime1::exception_handler_for_pc(JavaThread* thread) {
oop exception = thread->exception_oop();
address pc = thread->exception_pc();
// Still in Java mode
DEBUG_ONLY(ResetNoHandleMark rnhm);
nmethod* nm = NULL;
address continuation = NULL;
{
// Enter VM mode by calling the helper
ResetNoHandleMark rnhm;
continuation = exception_handler_for_pc_helper(thread, exception, pc, nm);
}
// Back in JAVA, use no oops DON'T safepoint
// Now check to see if the nmethod we were called from is now deoptimized.
// If so we must return to the deopt blob and deoptimize the nmethod
if (nm != NULL && caller_is_deopted()) {
continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
}
assert(continuation != NULL, "no handler found");
return continuation;
}
JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* thread, int index, arrayOopDesc* a))
NOT_PRODUCT(_throw_range_check_exception_count++;)
const int len = 35;
assert(len < strlen("Index %d out of bounds for length %d"), "Must allocate more space for message.");
char message[2 * jintAsStringSize + len];
sprintf(message, "Index %d out of bounds for length %d", index, a->length());
SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
JRT_END
JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* thread, int index))
NOT_PRODUCT(_throw_index_exception_count++;)
char message[16];
sprintf(message, "%d", index);
SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
JRT_END
JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* thread))
NOT_PRODUCT(_throw_div0_exception_count++;)
SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
JRT_END
JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* thread))
NOT_PRODUCT(_throw_null_pointer_exception_count++;)
SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_NullPointerException());
JRT_END
JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* thread, oopDesc* object))
NOT_PRODUCT(_throw_class_cast_exception_count++;)
ResourceMark rm(thread);
char* message = SharedRuntime::generate_class_cast_message(
thread, object->klass());
SharedRuntime::throw_and_post_jvmti_exception(
thread, vmSymbols::java_lang_ClassCastException(), message);
JRT_END
JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* thread))
NOT_PRODUCT(_throw_incompatible_class_change_error_count++;)
ResourceMark rm(thread);
SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IncompatibleClassChangeError());
JRT_END
JRT_ENTRY_NO_ASYNC(void, Runtime1::monitorenter(JavaThread* thread, oopDesc* obj, BasicObjectLock* lock))
NOT_PRODUCT(_monitorenter_slowcase_cnt++;)
if (PrintBiasedLockingStatistics) {
Atomic::inc(BiasedLocking::slow_path_entry_count_addr());
}
Handle h_obj(thread, obj);
if (!UseFastLocking) {
lock->set_obj(obj);
}
assert(obj == lock->obj(), "must match");
ObjectSynchronizer::enter(h_obj, lock->lock(), THREAD);
JRT_END
JRT_LEAF(void, Runtime1::monitorexit(JavaThread* thread, BasicObjectLock* lock))
NOT_PRODUCT(_monitorexit_slowcase_cnt++;)
assert(thread == JavaThread::current(), "threads must correspond");
assert(thread->last_Java_sp(), "last_Java_sp must be set");
// monitorexit is non-blocking (leaf routine) => no exceptions can be thrown
EXCEPTION_MARK;
oop obj = lock->obj();
assert(oopDesc::is_oop(obj), "must be NULL or an object");
ObjectSynchronizer::exit(obj, lock->lock(), THREAD);
JRT_END
// Cf. OptoRuntime::deoptimize_caller_frame
JRT_ENTRY(void, Runtime1::deoptimize(JavaThread* thread, jint trap_request))
// Called from within the owner thread, so no need for safepoint
RegisterMap reg_map(thread, false);
frame stub_frame = thread->last_frame();
assert(stub_frame.is_runtime_frame(), "Sanity check");
frame caller_frame = stub_frame.sender(®_map);
nmethod* nm = caller_frame.cb()->as_nmethod_or_null();
assert(nm != NULL, "Sanity check");
methodHandle method(thread, nm->method());
assert(nm == CodeCache::find_nmethod(caller_frame.pc()), "Should be the same");
Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
if (action == Deoptimization::Action_make_not_entrant) {
if (nm->make_not_entrant()) {
if (reason == Deoptimization::Reason_tenured) {
MethodData* trap_mdo = Deoptimization::get_method_data(thread, method, true /*create_if_missing*/);
if (trap_mdo != NULL) {
trap_mdo->inc_tenure_traps();
}
}
}
}
// Deoptimize the caller frame.
Deoptimization::deoptimize_frame(thread, caller_frame.id());
// Return to the now deoptimized frame.
JRT_END
#ifndef DEOPTIMIZE_WHEN_PATCHING
static Klass* resolve_field_return_klass(const methodHandle& caller, int bci, TRAPS) {
Bytecode_field field_access(caller, bci);
// This can be static or non-static field access
Bytecodes::Code code = field_access.code();
// We must load class, initialize class and resolve the field
fieldDescriptor result; // initialize class if needed
constantPoolHandle constants(THREAD, caller->constants());
LinkResolver::resolve_field_access(result, constants, field_access.index(), caller, Bytecodes::java_code(code), CHECK_NULL);
return result.field_holder();
}
//
// This routine patches sites where a class wasn't loaded or
// initialized at the time the code was generated. It handles
// references to classes, fields and forcing of initialization. Most
// of the cases are straightforward and involving simply forcing
// resolution of a class, rewriting the instruction stream with the
// needed constant and replacing the call in this function with the
// patched code. The case for static field is more complicated since
// the thread which is in the process of initializing a class can
// access it's static fields but other threads can't so the code
// either has to deoptimize when this case is detected or execute a
// check that the current thread is the initializing thread. The
// current
//
// Patches basically look like this:
//
//
// patch_site: jmp patch stub ;; will be patched
// continue: ...
// ...
// ...
// ...
//
// They have a stub which looks like this:
//
// ;; patch body
// movl <const>, reg (for class constants)
// <or> movl [reg1 + <const>], reg (for field offsets)
// <or> movl reg, [reg1 + <const>] (for field offsets)
// <being_init offset> <bytes to copy> <bytes to skip>
// patch_stub: call Runtime1::patch_code (through a runtime stub)
// jmp patch_site
//
//
// A normal patch is done by rewriting the patch body, usually a move,
// and then copying it into place over top of the jmp instruction
// being careful to flush caches and doing it in an MP-safe way. The
// constants following the patch body are used to find various pieces
// of the patch relative to the call site for Runtime1::patch_code.
// The case for getstatic and putstatic is more complicated because
// getstatic and putstatic have special semantics when executing while
// the class is being initialized. getstatic/putstatic on a class
// which is being_initialized may be executed by the initializing
// thread but other threads have to block when they execute it. This
// is accomplished in compiled code by executing a test of the current
// thread against the initializing thread of the class. It's emitted
// as boilerplate in their stub which allows the patched code to be
// executed before it's copied back into the main body of the nmethod.
//
// being_init: get_thread(<tmp reg>
// cmpl [reg1 + <init_thread_offset>], <tmp reg>
// jne patch_stub
// movl [reg1 + <const>], reg (for field offsets) <or>
// movl reg, [reg1 + <const>] (for field offsets)
// jmp continue
// <being_init offset> <bytes to copy> <bytes to skip>
// patch_stub: jmp Runtim1::patch_code (through a runtime stub)
// jmp patch_site
//
// If the class is being initialized the patch body is rewritten and
// the patch site is rewritten to jump to being_init, instead of
// patch_stub. Whenever this code is executed it checks the current
// thread against the intializing thread so other threads will enter
// the runtime and end up blocked waiting the class to finish
// initializing inside the calls to resolve_field below. The
// initializing class will continue on it's way. Once the class is
// fully_initialized, the intializing_thread of the class becomes
// NULL, so the next thread to execute this code will fail the test,
// call into patch_code and complete the patching process by copying
// the patch body back into the main part of the nmethod and resume
// executing.
// NB:
//
// Patchable instruction sequences inherently exhibit race conditions,
// where thread A is patching an instruction at the same time thread B
// is executing it. The algorithms we use ensure that any observation
// that B can make on any intermediate states during A's patching will
// always end up with a correct outcome. This is easiest if there are
// few or no intermediate states. (Some inline caches have two
// related instructions that must be patched in tandem. For those,
// intermediate states seem to be unavoidable, but we will get the
// right answer from all possible observation orders.)
//
// When patching the entry instruction at the head of a method, or a
// linkable call instruction inside of a method, we try very hard to
// use a patch sequence which executes as a single memory transaction.
// This means, in practice, that when thread A patches an instruction,
// it should patch a 32-bit or 64-bit word that somehow overlaps the
// instruction or is contained in it. We believe that memory hardware
// will never break up such a word write, if it is naturally aligned
// for the word being written. We also know that some CPUs work very
// hard to create atomic updates even of naturally unaligned words,
// but we don't want to bet the farm on this always working.
//
// Therefore, if there is any chance of a race condition, we try to
// patch only naturally aligned words, as single, full-word writes.
JRT_ENTRY(void, Runtime1::patch_code(JavaThread* thread, Runtime1::StubID stub_id ))
NOT_PRODUCT(_patch_code_slowcase_cnt++;)
ResourceMark rm(thread);
RegisterMap reg_map(thread, false);
frame runtime_frame = thread->last_frame();
frame caller_frame = runtime_frame.sender(®_map);
// last java frame on stack
vframeStream vfst(thread, true);
assert(!vfst.at_end(), "Java frame must exist");
methodHandle caller_method(THREAD, vfst.method());
// Note that caller_method->code() may not be same as caller_code because of OSR's
// Note also that in the presence of inlining it is not guaranteed
// that caller_method() == caller_code->method()
int bci = vfst.bci();
Bytecodes::Code code = caller_method()->java_code_at(bci);
// this is used by assertions in the access_field_patching_id
BasicType patch_field_type = T_ILLEGAL;
bool deoptimize_for_volatile = false;
bool deoptimize_for_atomic = false;
int patch_field_offset = -1;
Klass* init_klass = NULL; // klass needed by load_klass_patching code
Klass* load_klass = NULL; // klass needed by load_klass_patching code
Handle mirror(THREAD, NULL); // oop needed by load_mirror_patching code
Handle appendix(THREAD, NULL); // oop needed by appendix_patching code
bool load_klass_or_mirror_patch_id =
(stub_id == Runtime1::load_klass_patching_id || stub_id == Runtime1::load_mirror_patching_id);
if (stub_id == Runtime1::access_field_patching_id) {
Bytecode_field field_access(caller_method, bci);
fieldDescriptor result; // initialize class if needed
Bytecodes::Code code = field_access.code();
constantPoolHandle constants(THREAD, caller_method->constants());
LinkResolver::resolve_field_access(result, constants, field_access.index(), caller_method, Bytecodes::java_code(code), CHECK);
patch_field_offset = result.offset();
// If we're patching a field which is volatile then at compile it
// must not have been know to be volatile, so the generated code
// isn't correct for a volatile reference. The nmethod has to be
// deoptimized so that the code can be regenerated correctly.
// This check is only needed for access_field_patching since this
// is the path for patching field offsets. load_klass is only
// used for patching references to oops which don't need special
// handling in the volatile case.
deoptimize_for_volatile = result.access_flags().is_volatile();
// If we are patching a field which should be atomic, then
// the generated code is not correct either, force deoptimizing.
// We need to only cover T_LONG and T_DOUBLE fields, as we can
// break access atomicity only for them.
// Strictly speaking, the deoptimization on 64-bit platforms
// is unnecessary, and T_LONG stores on 32-bit platforms need
// to be handled by special patching code when AlwaysAtomicAccesses
// becomes product feature. At this point, we are still going
// for the deoptimization for consistency against volatile
// accesses.
patch_field_type = result.field_type();
deoptimize_for_atomic = (AlwaysAtomicAccesses && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG));
} else if (load_klass_or_mirror_patch_id) {
Klass* k = NULL;
switch (code) {
case Bytecodes::_putstatic:
case Bytecodes::_getstatic:
{ Klass* klass = resolve_field_return_klass(caller_method, bci, CHECK);
init_klass = klass;
mirror = Handle(THREAD, klass->java_mirror());
}
break;
case Bytecodes::_new:
{ Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
k = caller_method->constants()->klass_at(bnew.index(), CHECK);
}
break;
case Bytecodes::_multianewarray:
{ Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
k = caller_method->constants()->klass_at(mna.index(), CHECK);
}
break;
case Bytecodes::_instanceof:
{ Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
k = caller_method->constants()->klass_at(io.index(), CHECK);
}
break;
case Bytecodes::_checkcast:
{ Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
k = caller_method->constants()->klass_at(cc.index(), CHECK);
}
break;
case Bytecodes::_anewarray:
{ Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
Klass* ek = caller_method->constants()->klass_at(anew.index(), CHECK);
k = ek->array_klass(CHECK);
}
break;
case Bytecodes::_ldc:
case Bytecodes::_ldc_w:
{
Bytecode_loadconstant cc(caller_method, bci);
oop m = cc.resolve_constant(CHECK);
mirror = Handle(THREAD, m);
}
break;
default: fatal("unexpected bytecode for load_klass_or_mirror_patch_id");
}
load_klass = k;
} else if (stub_id == load_appendix_patching_id) {
Bytecode_invoke bytecode(caller_method, bci);
Bytecodes::Code bc = bytecode.invoke_code();
CallInfo info;
constantPoolHandle pool(thread, caller_method->constants());
int index = bytecode.index();
LinkResolver::resolve_invoke(info, Handle(), pool, index, bc, CHECK);
switch (bc) {
case Bytecodes::_invokehandle: {
int cache_index = ConstantPool::decode_cpcache_index(index, true);
assert(cache_index >= 0 && cache_index < pool->cache()->length(), "unexpected cache index");
ConstantPoolCacheEntry* cpce = pool->cache()->entry_at(cache_index);
cpce->set_method_handle(pool, info);
appendix = Handle(THREAD, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
break;
}
case Bytecodes::_invokedynamic: {
ConstantPoolCacheEntry* cpce = pool->invokedynamic_cp_cache_entry_at(index);
cpce->set_dynamic_call(pool, info);
appendix = Handle(THREAD, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
break;
}
default: fatal("unexpected bytecode for load_appendix_patching_id");
}
} else {
ShouldNotReachHere();
}
if (deoptimize_for_volatile || deoptimize_for_atomic) {
// At compile time we assumed the field wasn't volatile/atomic but after
// loading it turns out it was volatile/atomic so we have to throw the
// compiled code out and let it be regenerated.
if (TracePatching) {
if (deoptimize_for_volatile) {
tty->print_cr("Deoptimizing for patching volatile field reference");
}
if (deoptimize_for_atomic) {
tty->print_cr("Deoptimizing for patching atomic field reference");
}
}
// It's possible the nmethod was invalidated in the last
// safepoint, but if it's still alive then make it not_entrant.
nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
if (nm != NULL) {
nm->make_not_entrant();
}
Deoptimization::deoptimize_frame(thread, caller_frame.id());
// Return to the now deoptimized frame.
}
// Now copy code back
{
MutexLocker ml_patch (Patching_lock, Mutex::_no_safepoint_check_flag);
//
// Deoptimization may have happened while we waited for the lock.
// In that case we don't bother to do any patching we just return
// and let the deopt happen
if (!caller_is_deopted()) {
NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
address instr_pc = jump->jump_destination();
NativeInstruction* ni = nativeInstruction_at(instr_pc);
if (ni->is_jump() ) {
// the jump has not been patched yet
// The jump destination is slow case and therefore not part of the stubs
// (stubs are only for StaticCalls)
// format of buffer
// ....
// instr byte 0 <-- copy_buff
// instr byte 1
// ..
// instr byte n-1
// n
// .... <-- call destination
address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
unsigned char* byte_count = (unsigned char*) (stub_location - 1);
unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
address copy_buff = stub_location - *byte_skip - *byte_count;
address being_initialized_entry = stub_location - *being_initialized_entry_offset;
if (TracePatching) {
ttyLocker ttyl;
tty->print_cr(" Patching %s at bci %d at address " INTPTR_FORMAT " (%s)", Bytecodes::name(code), bci,
p2i(instr_pc), (stub_id == Runtime1::access_field_patching_id) ? "field" : "klass");
nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
assert(caller_code != NULL, "nmethod not found");
// NOTE we use pc() not original_pc() because we already know they are
// identical otherwise we'd have never entered this block of code
const ImmutableOopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
assert(map != NULL, "null check");
map->print();
tty->cr();
Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
}
// depending on the code below, do_patch says whether to copy the patch body back into the nmethod
bool do_patch = true;
if (stub_id == Runtime1::access_field_patching_id) {
// The offset may not be correct if the class was not loaded at code generation time.
// Set it now.
NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
assert(patch_field_offset >= 0, "illegal offset");
n_move->add_offset_in_bytes(patch_field_offset);
} else if (load_klass_or_mirror_patch_id) {
// If a getstatic or putstatic is referencing a klass which
// isn't fully initialized, the patch body isn't copied into
// place until initialization is complete. In this case the
// patch site is setup so that any threads besides the
// initializing thread are forced to come into the VM and
// block.
do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
InstanceKlass::cast(init_klass)->is_initialized();
NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
if (jump->jump_destination() == being_initialized_entry) {
assert(do_patch == true, "initialization must be complete at this point");
} else {
// patch the instruction <move reg, klass>
NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
assert(n_copy->data() == 0 ||
n_copy->data() == (intptr_t)Universe::non_oop_word(),
"illegal init value");
if (stub_id == Runtime1::load_klass_patching_id) {
assert(load_klass != NULL, "klass not set");
n_copy->set_data((intx) (load_klass));
} else {
assert(mirror() != NULL, "klass not set");
// Don't need a G1 pre-barrier here since we assert above that data isn't an oop.
n_copy->set_data(cast_from_oop<intx>(mirror()));
}
if (TracePatching) {
Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
}
}
} else if (stub_id == Runtime1::load_appendix_patching_id) {
NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
assert(n_copy->data() == 0 ||
n_copy->data() == (intptr_t)Universe::non_oop_word(),
"illegal init value");
n_copy->set_data(cast_from_oop<intx>(appendix()));
if (TracePatching) {
Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
}
} else {
ShouldNotReachHere();
}
#if defined(SPARC) || defined(PPC32)
if (load_klass_or_mirror_patch_id ||
stub_id == Runtime1::load_appendix_patching_id) {
// Update the location in the nmethod with the proper
// metadata. When the code was generated, a NULL was stuffed
// in the metadata table and that table needs to be update to
// have the right value. On intel the value is kept
// directly in the instruction instead of in the metadata
// table, so set_data above effectively updated the value.
nmethod* nm = CodeCache::find_nmethod(instr_pc);
assert(nm != NULL, "invalid nmethod_pc");
RelocIterator mds(nm, copy_buff, copy_buff + 1);
bool found = false;
while (mds.next() && !found) {
if (mds.type() == relocInfo::oop_type) {
assert(stub_id == Runtime1::load_mirror_patching_id ||
stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
oop_Relocation* r = mds.oop_reloc();
oop* oop_adr = r->oop_addr();
*oop_adr = stub_id == Runtime1::load_mirror_patching_id ? mirror() : appendix();
r->fix_oop_relocation();
found = true;
} else if (mds.type() == relocInfo::metadata_type) {
assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
metadata_Relocation* r = mds.metadata_reloc();
Metadata** metadata_adr = r->metadata_addr();
*metadata_adr = load_klass;
r->fix_metadata_relocation();
found = true;
}
}
assert(found, "the metadata must exist!");
}
#endif
if (do_patch) {
// replace instructions
// first replace the tail, then the call
#ifdef ARM
if((load_klass_or_mirror_patch_id ||
stub_id == Runtime1::load_appendix_patching_id) &&
nativeMovConstReg_at(copy_buff)->is_pc_relative()) {
nmethod* nm = CodeCache::find_nmethod(instr_pc);
address addr = NULL;
assert(nm != NULL, "invalid nmethod_pc");
RelocIterator mds(nm, copy_buff, copy_buff + 1);
while (mds.next()) {
if (mds.type() == relocInfo::oop_type) {
assert(stub_id == Runtime1::load_mirror_patching_id ||
stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
oop_Relocation* r = mds.oop_reloc();
addr = (address)r->oop_addr();
break;
} else if (mds.type() == relocInfo::metadata_type) {
assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
metadata_Relocation* r = mds.metadata_reloc();
addr = (address)r->metadata_addr();
break;
}
}
assert(addr != NULL, "metadata relocation must exist");
copy_buff -= *byte_count;
NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
n_copy2->set_pc_relative_offset(addr, instr_pc);
}
#endif
for (int i = NativeGeneralJump::instruction_size; i < *byte_count; i++) {
address ptr = copy_buff + i;
int a_byte = (*ptr) & 0xFF;
address dst = instr_pc + i;
*(unsigned char*)dst = (unsigned char) a_byte;
}
ICache::invalidate_range(instr_pc, *byte_count);
NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
if (load_klass_or_mirror_patch_id ||
stub_id == Runtime1::load_appendix_patching_id) {
relocInfo::relocType rtype =
(stub_id == Runtime1::load_klass_patching_id) ?
relocInfo::metadata_type :
relocInfo::oop_type;
// update relocInfo to metadata
nmethod* nm = CodeCache::find_nmethod(instr_pc);
assert(nm != NULL, "invalid nmethod_pc");
// The old patch site is now a move instruction so update
// the reloc info so that it will get updated during
// future GCs.
RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
relocInfo::none, rtype);
#ifdef SPARC
// Sparc takes two relocations for an metadata so update the second one.
address instr_pc2 = instr_pc + NativeMovConstReg::add_offset;
RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
relocInfo::none, rtype);
#endif
#ifdef PPC32
{ address instr_pc2 = instr_pc + NativeMovConstReg::lo_offset;
RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
relocInfo::none, rtype);
}
#endif
}
} else {
ICache::invalidate_range(copy_buff, *byte_count);
NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
}
}
}
}
// If we are patching in a non-perm oop, make sure the nmethod
// is on the right list.
{
MutexLocker ml_code (CodeCache_lock, Mutex::_no_safepoint_check_flag);
nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
guarantee(nm != NULL, "only nmethods can contain non-perm oops");
// Since we've patched some oops in the nmethod,
// (re)register it with the heap.
Universe::heap()->register_nmethod(nm);
}
JRT_END
#else // DEOPTIMIZE_WHEN_PATCHING
JRT_ENTRY(void, Runtime1::patch_code(JavaThread* thread, Runtime1::StubID stub_id ))
RegisterMap reg_map(thread, false);
NOT_PRODUCT(_patch_code_slowcase_cnt++;)
if (TracePatching) {
tty->print_cr("Deoptimizing because patch is needed");
}
frame runtime_frame = thread->last_frame();
frame caller_frame = runtime_frame.sender(®_map);
// It's possible the nmethod was invalidated in the last
// safepoint, but if it's still alive then make it not_entrant.
nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
if (nm != NULL) {
nm->make_not_entrant();
}
Deoptimization::deoptimize_frame(thread, caller_frame.id());
// Return to the now deoptimized frame.
JRT_END
#endif // DEOPTIMIZE_WHEN_PATCHING
//
// Entry point for compiled code. We want to patch a nmethod.
// We don't do a normal VM transition here because we want to
// know after the patching is complete and any safepoint(s) are taken
// if the calling nmethod was deoptimized. We do this by calling a
// helper method which does the normal VM transition and when it
// completes we can check for deoptimization. This simplifies the
// assembly code in the cpu directories.
//
int Runtime1::move_klass_patching(JavaThread* thread) {
//
// NOTE: we are still in Java
//
Thread* THREAD = thread;
debug_only(NoHandleMark nhm;)
{
// Enter VM mode
ResetNoHandleMark rnhm;
patch_code(thread, load_klass_patching_id);
}
// Back in JAVA, use no oops DON'T safepoint
// Return true if calling code is deoptimized
return caller_is_deopted();
}
int Runtime1::move_mirror_patching(JavaThread* thread) {
//
// NOTE: we are still in Java
//
Thread* THREAD = thread;
debug_only(NoHandleMark nhm;)
{
// Enter VM mode
ResetNoHandleMark rnhm;
patch_code(thread, load_mirror_patching_id);
}
// Back in JAVA, use no oops DON'T safepoint
// Return true if calling code is deoptimized
return caller_is_deopted();
}
int Runtime1::move_appendix_patching(JavaThread* thread) {
//
// NOTE: we are still in Java
//
Thread* THREAD = thread;
debug_only(NoHandleMark nhm;)
{
// Enter VM mode
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