/* * Copyright (c) 1999, 2010, 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 "incls/_precompiled.incl" #include "incls/_c1_Runtime1.cpp.incl" // 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::_primitive_arraycopy_cnt = 0; int Runtime1::_oop_arraycopy_cnt = 0; int Runtime1::_arraycopy_slowcase_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; #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); // bypass VM_DeoptimizeFrame and deoptimize the frame directly Deoptimization::deoptimize_frame(thread, caller_frame.id()); assert(caller_is_deopted(), "Must be deoptimized"); } } void Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubID id) { assert(0 <= id && id < number_of_ids, "illegal stub id"); ResourceMark rm; // create code buffer for code storage CodeBuffer code(buffer_blob->instructions_begin(), buffer_blob->instructions_size()); Compilation::setup_code_buffer(&code, 0); // create assembler for code generation StubAssembler* sasm = new StubAssembler(&code, name_for(id), id); // generate code for runtime stub OopMapSet* oop_maps; oop_maps = generate_code_for(id, sasm); assert(oop_maps == NULL || sasm->frame_size() != no_frame_size, "if stub has an oop map it must have a valid frame size"); #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 g1_pre_barrier_slow_id: case g1_post_barrier_slow_id: case slow_subtype_check_id: case fpu2long_stub_id: case unwind_exception_id: #ifndef TIERED case counter_overflow_id: // Not generated outside the tiered world #endif #ifdef SPARC case handle_exception_nofpu_id: // Unused on sparc #endif break; // All other stubs should have oopmaps default: assert(oop_maps != NULL, "must have an oopmap"); } #endif // 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(); // create blob - distinguish a few special cases CodeBlob* blob = RuntimeStub::new_runtime_stub(name_for(id), &code, CodeOffsets::frame_never_safe, sasm->frame_size(), oop_maps, sasm->must_gc_arguments()); // install blob assert(blob != NULL, "blob must exist"); _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 } 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); } #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, trace_block_entry); #undef FUNCTION_CASE return ""; } JRT_ENTRY(void, Runtime1::new_instance(JavaThread* thread, klassOopDesc* klass)) NOT_PRODUCT(_new_instance_slowcase_cnt++;) assert(oop(klass)->is_klass(), "not a class"); instanceKlassHandle h(thread, 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, klassOopDesc* 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(oop(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, klassOopDesc* 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(oop(array_klass)->is_klass(), "not a class"); klassOop 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, klassOopDesc* klass, int rank, jint* dims)) NOT_PRODUCT(_new_multi_array_slowcase_cnt++;) assert(oop(klass)->is_klass(), "not a class"); assert(rank >= 1, "rank must be nonzero"); 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)) THROW(vmSymbolHandles::java_lang_ArrayStoreException()); JRT_END JRT_ENTRY(void, Runtime1::post_jvmti_exception_throw(JavaThread* thread)) if (JvmtiExport::can_post_on_exceptions()) { vframeStream vfst(thread, true); address bcp = vfst.method()->bcp_from(vfst.bci()); JvmtiExport::post_exception_throw(thread, vfst.method(), bcp, thread->exception_oop()); } JRT_END #ifdef TIERED JRT_ENTRY(void, Runtime1::counter_overflow(JavaThread* thread, int bci)) RegisterMap map(thread, false); frame fr = thread->last_frame().sender(&map); nmethod* nm = (nmethod*) fr.cb(); assert(nm!= NULL && nm->is_nmethod(), "what?"); methodHandle method(thread, nm->method()); if (bci == 0) { // invocation counter overflow if (!Tier1CountOnly) { CompilationPolicy::policy()->method_invocation_event(method, CHECK); } else { method()->invocation_counter()->reset(); } } else { if (!Tier1CountOnly) { // Twe have a bci but not the destination bci and besides a backedge // event is more for OSR which we don't want here. CompilationPolicy::policy()->method_invocation_event(method, CHECK); } else { method()->backedge_counter()->reset(); } } JRT_END #endif // TIERED 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)) 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"); assert(exception->is_oop(), "just checking"); // 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_yellow_zone_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. VM_DeoptimizeFrame deopt(thread, caller_frame.id()); VMThread::execute(&deopt); return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls(); } // ExceptionCache is used only for exceptions at call and not for implicit exceptions if (guard_pages_enabled) { address fast_continuation = nm->handler_for_exception_and_pc(exception, pc); if (fast_continuation != NULL) { if (fast_continuation == ExceptionCache::unwind_handler()) fast_continuation = NULL; 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 (TraceExceptions) { ttyLocker ttyl; ResourceMark rm; tty->print_cr("Exception <%s> (0x%x) thrown in compiled method <%s> at PC " PTR_FORMAT " for thread 0x%x", exception->print_value_string(), (address)exception(), nm->method()->print_value_string(), pc, thread); } // for AbortVMOnException flag NOT_PRODUCT(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->set_exception_oop(NULL); thread->set_exception_pc(NULL); continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false); // 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 if (continuation == NULL) { nm->add_handler_for_exception_and_pc(exception, pc, ExceptionCache::unwind_handler()); } else { nm->add_handler_for_exception_and_pc(exception, pc, continuation); } } thread->set_vm_result(exception()); if (TraceExceptions) { ttyLocker ttyl; ResourceMark rm; tty->print_cr("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT " for exception thrown at PC " PTR_FORMAT, thread, continuation, 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(); } return continuation; } JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* thread, int index)) NOT_PRODUCT(_throw_range_check_exception_count++;) Events::log("throw_range_check"); char message[jintAsStringSize]; sprintf(message, "%d", index); 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++;) Events::log("throw_index"); 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, Klass::cast(object->klass())->external_name()); 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); assert(h_obj()->is_oop(), "must be NULL or an object"); if (UseBiasedLocking) { // Retry fast entry if bias is revoked to avoid unnecessary inflation ObjectSynchronizer::fast_enter(h_obj, lock->lock(), true, CHECK); } else { if (UseFastLocking) { // When using fast locking, the compiled code has already tried the fast case assert(obj == lock->obj(), "must match"); ObjectSynchronizer::slow_enter(h_obj, lock->lock(), THREAD); } else { lock->set_obj(obj); ObjectSynchronizer::fast_enter(h_obj, lock->lock(), false, 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(obj->is_oop(), "must be NULL or an object"); if (UseFastLocking) { // When using fast locking, the compiled code has already tried the fast case ObjectSynchronizer::slow_exit(obj, lock->lock(), THREAD); } else { ObjectSynchronizer::fast_exit(obj, lock->lock(), THREAD); } JRT_END static klassOop resolve_field_return_klass(methodHandle caller, int bci, TRAPS) { Bytecode_field* field_access = Bytecode_field_at(caller, bci); // This can be static or non-static field access Bytecodes::Code code = field_access->code(); // We must load class, initialize class and resolvethe field FieldAccessInfo result; // initialize class if needed constantPoolHandle constants(THREAD, caller->constants()); LinkResolver::resolve_field(result, constants, field_access->index(), Bytecodes::java_code(code), false, CHECK_NULL); return result.klass()(); } // // 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 , reg (for class constants) // movl [reg1 + ], reg (for field offsets) // movl reg, [reg1 + ] (for field offsets) // // 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( // cmpl [reg1 + ], // jne patch_stub // movl [reg1 + ], reg (for field offsets) // movl reg, [reg1 + ] (for field offsets) // jmp continue // // 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. // // 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(); Events::log("patch_code @ " INTPTR_FORMAT , caller_frame.pc()); Bytecodes::Code code = Bytecode_at(caller_method->bcp_from(bci))->java_code(); #ifndef PRODUCT // this is used by assertions in the access_field_patching_id BasicType patch_field_type = T_ILLEGAL; #endif // PRODUCT bool deoptimize_for_volatile = false; int patch_field_offset = -1; KlassHandle init_klass(THREAD, klassOop(NULL)); // klass needed by access_field_patching code Handle load_klass(THREAD, NULL); // oop needed by load_klass_patching code if (stub_id == Runtime1::access_field_patching_id) { Bytecode_field* field_access = Bytecode_field_at(caller_method, bci); FieldAccessInfo result; // initialize class if needed Bytecodes::Code code = field_access->code(); constantPoolHandle constants(THREAD, caller_method->constants()); LinkResolver::resolve_field(result, constants, field_access->index(), Bytecodes::java_code(code), false, CHECK); patch_field_offset = result.field_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(); #ifndef PRODUCT patch_field_type = result.field_type(); #endif } else if (stub_id == Runtime1::load_klass_patching_id) { oop k; switch (code) { case Bytecodes::_putstatic: case Bytecodes::_getstatic: { klassOop klass = resolve_field_return_klass(caller_method, bci, CHECK); // Save a reference to the class that has to be checked for initialization init_klass = KlassHandle(THREAD, klass); k = klass; } break; case Bytecodes::_new: { Bytecode_new* bnew = Bytecode_new_at(caller_method->bcp_from(bci)); k = caller_method->constants()->klass_at(bnew->index(), CHECK); } break; case Bytecodes::_multianewarray: { Bytecode_multianewarray* mna = Bytecode_multianewarray_at(caller_method->bcp_from(bci)); k = caller_method->constants()->klass_at(mna->index(), CHECK); } break; case Bytecodes::_instanceof: { Bytecode_instanceof* io = Bytecode_instanceof_at(caller_method->bcp_from(bci)); k = caller_method->constants()->klass_at(io->index(), CHECK); } break; case Bytecodes::_checkcast: { Bytecode_checkcast* cc = Bytecode_checkcast_at(caller_method->bcp_from(bci)); k = caller_method->constants()->klass_at(cc->index(), CHECK); } break; case Bytecodes::_anewarray: { Bytecode_anewarray* anew = Bytecode_anewarray_at(caller_method->bcp_from(bci)); klassOop ek = caller_method->constants()->klass_at(anew->index(), CHECK); k = Klass::cast(ek)->array_klass(CHECK); } break; case Bytecodes::_ldc: case Bytecodes::_ldc_w: { Bytecode_loadconstant* cc = Bytecode_loadconstant_at(caller_method, bci); k = cc->resolve_constant(CHECK); assert(k != NULL && !k->is_klass(), "must be class mirror or other Java constant"); } break; default: Unimplemented(); } // convert to handle load_klass = Handle(THREAD, k); } else { ShouldNotReachHere(); } if (deoptimize_for_volatile) { // At compile time we assumed the field wasn't volatile but after // loading it turns out it was volatile so we have to throw the // compiled code out and let it be regenerated. if (TracePatching) { tty->print_cr("Deoptimizing for patching volatile 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(); } VM_DeoptimizeFrame deopt(thread, caller_frame.id()); VMThread::execute(&deopt); // Return to the now deoptimized frame. } // If we are patching in a non-perm oop, make sure the nmethod // is on the right list. if (ScavengeRootsInCode && load_klass.not_null() && load_klass->is_scavengable()) { MutexLockerEx 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"); if (!nm->on_scavenge_root_list()) CodeCache::add_scavenge_root_nmethod(nm); } // Now copy code back { MutexLockerEx 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) { tty->print_cr(" Patching %s at bci %d at address 0x%x (%s)", Bytecodes::name(code), bci, 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 OopMap* 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 (stub_id == Runtime1::load_klass_patching_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 NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff); assert(n_copy->data() == 0, "illegal init value"); assert(load_klass() != NULL, "klass not set"); n_copy->set_data((intx) (load_klass())); if (TracePatching) { Disassembler::decode(copy_buff, copy_buff + *byte_count, tty); } #ifdef SPARC // Update the oop location in the nmethod with the proper // oop. When the code was generated, a NULL was stuffed // in the oop 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 oop // table, so set_data above effectively updated the value. nmethod* nm = CodeCache::find_nmethod(instr_pc); assert(nm != NULL, "invalid nmethod_pc"); RelocIterator oops(nm, copy_buff, copy_buff + 1); bool found = false; while (oops.next() && !found) { if (oops.type() == relocInfo::oop_type) { oop_Relocation* r = oops.oop_reloc(); oop* oop_adr = r->oop_addr(); *oop_adr = load_klass(); r->fix_oop_relocation(); found = true; } } assert(found, "the oop must exist!"); #endif } } else { ShouldNotReachHere(); } if (do_patch) { // replace instructions // first replace the tail, then the call for (int i = NativeCall::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 (stub_id == Runtime1::load_klass_patching_id) { // update relocInfo to oop 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, relocInfo::oop_type); #ifdef SPARC // Sparc takes two relocations for an oop 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, relocInfo::oop_type); #endif } } else { ICache::invalidate_range(copy_buff, *byte_count); NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry); } } } } JRT_END // // 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(); } // // 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::access_field_patching(JavaThread* thread) { // // NOTE: we are still in Java // Thread* THREAD = thread; debug_only(NoHandleMark nhm;) { // Enter VM mode ResetNoHandleMark rnhm; patch_code(thread, access_field_patching_id); } // Back in JAVA, use no oops DON'T safepoint // Return true if calling code is deoptimized return caller_is_deopted(); JRT_END JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id)) // for now we just print out the block id tty->print("%d ", block_id); JRT_END // Array copy return codes. enum { ac_failed = -1, // arraycopy failed ac_ok = 0 // arraycopy succeeded }; // Below length is the # elements copied. template int obj_arraycopy_work(oopDesc* src, T* src_addr, oopDesc* dst, T* dst_addr, int length) { // For performance reasons, we assume we are using a card marking write // barrier. The assert will fail if this is not the case. // Note that we use the non-virtual inlineable variant of write_ref_array. BarrierSet* bs = Universe::heap()->barrier_set(); assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt"); assert(bs->has_write_ref_array_pre_opt(), "For pre-barrier as well."); if (src == dst) { // same object, no check bs->write_ref_array_pre(dst_addr, length); Copy::conjoint_oops_atomic(src_addr, dst_addr, length); bs->write_ref_array((HeapWord*)dst_addr, length); return ac_ok; } else { klassOop bound = objArrayKlass::cast(dst->klass())->element_klass(); klassOop stype = objArrayKlass::cast(src->klass())->element_klass(); if (stype == bound || Klass::cast(stype)->is_subtype_of(bound)) { // Elements are guaranteed to be subtypes, so no check necessary bs->write_ref_array_pre(dst_addr, length); Copy::conjoint_oops_atomic(src_addr, dst_addr, length); bs->write_ref_array((HeapWord*)dst_addr, length); return ac_ok; } } return ac_failed; } // fast and direct copy of arrays; returning -1, means that an exception may be thrown // and we did not copy anything JRT_LEAF(int, Runtime1::arraycopy(oopDesc* src, int src_pos, oopDesc* dst, int dst_pos, int length)) #ifndef PRODUCT _generic_arraycopy_cnt++; // Slow-path oop array copy #endif if (src == NULL || dst == NULL || src_pos < 0 || dst_pos < 0 || length < 0) return ac_failed; if (!dst->is_array() || !src->is_array()) return ac_failed; if ((unsigned int) arrayOop(src)->length() < (unsigned int)src_pos + (unsigned int)length) return ac_failed; if ((unsigned int) arrayOop(dst)->length() < (unsigned int)dst_pos + (unsigned int)length) return ac_failed; if (length == 0) return ac_ok; if (src->is_typeArray()) { const klassOop klass_oop = src->klass(); if (klass_oop != dst->klass()) return ac_failed; typeArrayKlass* klass = typeArrayKlass::cast(klass_oop); const int l2es = klass->log2_element_size(); const int ihs = klass->array_header_in_bytes() / wordSize; char* src_addr = (char*) ((oopDesc**)src + ihs) + (src_pos << l2es); char* dst_addr = (char*) ((oopDesc**)dst + ihs) + (dst_pos << l2es); // Potential problem: memmove is not guaranteed to be word atomic // Revisit in Merlin memmove(dst_addr, src_addr, length << l2es); return ac_ok; } else if (src->is_objArray() && dst->is_objArray()) { if (UseCompressedOops) { // will need for tiered narrowOop *src_addr = objArrayOop(src)->obj_at_addr(src_pos); narrowOop *dst_addr = objArrayOop(dst)->obj_at_addr(dst_pos); return obj_arraycopy_work(src, src_addr, dst, dst_addr, length); } else { oop *src_addr = objArrayOop(src)->obj_at_addr(src_pos); oop *dst_addr = objArrayOop(dst)->obj_at_addr(dst_pos); return obj_arraycopy_work(src, src_addr, dst, dst_addr, length); } } return ac_failed; JRT_END JRT_LEAF(void, Runtime1::primitive_arraycopy(HeapWord* src, HeapWord* dst, int length)) #ifndef PRODUCT _primitive_arraycopy_cnt++; #endif if (length == 0) return; // Not guaranteed to be word atomic, but that doesn't matter // for anything but an oop array, which is covered by oop_arraycopy. Copy::conjoint_jbytes(src, dst, length); JRT_END JRT_LEAF(void, Runtime1::oop_arraycopy(HeapWord* src, HeapWord* dst, int num)) #ifndef PRODUCT _oop_arraycopy_cnt++; #endif if (num == 0) return; BarrierSet* bs = Universe::heap()->barrier_set(); assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt"); assert(bs->has_write_ref_array_pre_opt(), "For pre-barrier as well."); if (UseCompressedOops) { bs->write_ref_array_pre((narrowOop*)dst, num); } else { bs->write_ref_array_pre((oop*)dst, num); } Copy::conjoint_oops_atomic((oop*) src, (oop*) dst, num); bs->write_ref_array(dst, num); JRT_END #ifndef PRODUCT void Runtime1::print_statistics() { tty->print_cr("C1 Runtime statistics:"); tty->print_cr(" _resolve_invoke_virtual_cnt: %d", SharedRuntime::_resolve_virtual_ctr); tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %d", SharedRuntime::_resolve_opt_virtual_ctr); tty->print_cr(" _resolve_invoke_static_cnt: %d", SharedRuntime::_resolve_static_ctr); tty->print_cr(" _handle_wrong_method_cnt: %d", SharedRuntime::_wrong_method_ctr); tty->print_cr(" _ic_miss_cnt: %d", SharedRuntime::_ic_miss_ctr); tty->print_cr(" _generic_arraycopy_cnt: %d", _generic_arraycopy_cnt); tty->print_cr(" _primitive_arraycopy_cnt: %d", _primitive_arraycopy_cnt); tty->print_cr(" _oop_arraycopy_cnt: %d", _oop_arraycopy_cnt); tty->print_cr(" _arraycopy_slowcase_cnt: %d", _arraycopy_slowcase_cnt); tty->print_cr(" _new_type_array_slowcase_cnt: %d", _new_type_array_slowcase_cnt); tty->print_cr(" _new_object_array_slowcase_cnt: %d", _new_object_array_slowcase_cnt); tty->print_cr(" _new_instance_slowcase_cnt: %d", _new_instance_slowcase_cnt); tty->print_cr(" _new_multi_array_slowcase_cnt: %d", _new_multi_array_slowcase_cnt); tty->print_cr(" _monitorenter_slowcase_cnt: %d", _monitorenter_slowcase_cnt); tty->print_cr(" _monitorexit_slowcase_cnt: %d", _monitorexit_slowcase_cnt); tty->print_cr(" _patch_code_slowcase_cnt: %d", _patch_code_slowcase_cnt); tty->print_cr(" _throw_range_check_exception_count: %d:", _throw_range_check_exception_count); tty->print_cr(" _throw_index_exception_count: %d:", _throw_index_exception_count); tty->print_cr(" _throw_div0_exception_count: %d:", _throw_div0_exception_count); tty->print_cr(" _throw_null_pointer_exception_count: %d:", _throw_null_pointer_exception_count); tty->print_cr(" _throw_class_cast_exception_count: %d:", _throw_class_cast_exception_count); tty->print_cr(" _throw_incompatible_class_change_error_count: %d:", _throw_incompatible_class_change_error_count); tty->print_cr(" _throw_array_store_exception_count: %d:", _throw_array_store_exception_count); tty->print_cr(" _throw_count: %d:", _throw_count); SharedRuntime::print_ic_miss_histogram(); tty->cr(); } #endif // PRODUCT