diff -r 000000000000 -r f90c822e73f8 src/share/vm/interpreter/oopMapCache.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/interpreter/oopMapCache.cpp Wed Apr 27 01:25:04 2016 +0800 @@ -0,0 +1,611 @@ +/* + * Copyright (c) 1997, 2014, 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 "interpreter/oopMapCache.hpp" +#include "memory/allocation.inline.hpp" +#include "memory/resourceArea.hpp" +#include "oops/oop.inline.hpp" +#include "prims/jvmtiRedefineClassesTrace.hpp" +#include "runtime/handles.inline.hpp" +#include "runtime/signature.hpp" + +PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC + +class OopMapCacheEntry: private InterpreterOopMap { + friend class InterpreterOopMap; + friend class OopMapForCacheEntry; + friend class OopMapCache; + friend class VerifyClosure; + + protected: + // Initialization + void fill(methodHandle method, int bci); + // fills the bit mask for native calls + void fill_for_native(methodHandle method); + void set_mask(CellTypeState* vars, CellTypeState* stack, int stack_top); + + // Deallocate bit masks and initialize fields + void flush(); + + private: + void allocate_bit_mask(); // allocates the bit mask on C heap f necessary + void deallocate_bit_mask(); // allocates the bit mask on C heap f necessary + bool verify_mask(CellTypeState *vars, CellTypeState *stack, int max_locals, int stack_top); + + public: + OopMapCacheEntry() : InterpreterOopMap() { +#ifdef ASSERT + _resource_allocate_bit_mask = false; +#endif + } +}; + + +// Implementation of OopMapForCacheEntry +// (subclass of GenerateOopMap, initializes an OopMapCacheEntry for a given method and bci) + +class OopMapForCacheEntry: public GenerateOopMap { + OopMapCacheEntry *_entry; + int _bci; + int _stack_top; + + virtual bool report_results() const { return false; } + virtual bool possible_gc_point (BytecodeStream *bcs); + virtual void fill_stackmap_prolog (int nof_gc_points); + virtual void fill_stackmap_epilog (); + virtual void fill_stackmap_for_opcodes (BytecodeStream *bcs, + CellTypeState* vars, + CellTypeState* stack, + int stack_top); + virtual void fill_init_vars (GrowableArray *init_vars); + + public: + OopMapForCacheEntry(methodHandle method, int bci, OopMapCacheEntry *entry); + + // Computes stack map for (method,bci) and initialize entry + void compute_map(TRAPS); + int size(); +}; + + +OopMapForCacheEntry::OopMapForCacheEntry(methodHandle method, int bci, OopMapCacheEntry* entry) : GenerateOopMap(method) { + _bci = bci; + _entry = entry; + _stack_top = -1; +} + + +void OopMapForCacheEntry::compute_map(TRAPS) { + assert(!method()->is_native(), "cannot compute oop map for native methods"); + // First check if it is a method where the stackmap is always empty + if (method()->code_size() == 0 || method()->max_locals() + method()->max_stack() == 0) { + _entry->set_mask_size(0); + } else { + ResourceMark rm; + GenerateOopMap::compute_map(CATCH); + result_for_basicblock(_bci); + } +} + + +bool OopMapForCacheEntry::possible_gc_point(BytecodeStream *bcs) { + return false; // We are not reporting any result. We call result_for_basicblock directly +} + + +void OopMapForCacheEntry::fill_stackmap_prolog(int nof_gc_points) { + // Do nothing +} + + +void OopMapForCacheEntry::fill_stackmap_epilog() { + // Do nothing +} + + +void OopMapForCacheEntry::fill_init_vars(GrowableArray *init_vars) { + // Do nothing +} + + +void OopMapForCacheEntry::fill_stackmap_for_opcodes(BytecodeStream *bcs, + CellTypeState* vars, + CellTypeState* stack, + int stack_top) { + // Only interested in one specific bci + if (bcs->bci() == _bci) { + _entry->set_mask(vars, stack, stack_top); + _stack_top = stack_top; + } +} + + +int OopMapForCacheEntry::size() { + assert(_stack_top != -1, "compute_map must be called first"); + return ((method()->is_static()) ? 0 : 1) + method()->max_locals() + _stack_top; +} + + +// Implementation of InterpreterOopMap and OopMapCacheEntry + +class VerifyClosure : public OffsetClosure { + private: + OopMapCacheEntry* _entry; + bool _failed; + + public: + VerifyClosure(OopMapCacheEntry* entry) { _entry = entry; _failed = false; } + void offset_do(int offset) { if (!_entry->is_oop(offset)) _failed = true; } + bool failed() const { return _failed; } +}; + +InterpreterOopMap::InterpreterOopMap() { + initialize(); +#ifdef ASSERT + _resource_allocate_bit_mask = true; +#endif +} + +InterpreterOopMap::~InterpreterOopMap() { + // The expection is that the bit mask was allocated + // last in this resource area. That would make the free of the + // bit_mask effective (see how FREE_RESOURCE_ARRAY does a free). + // If it was not allocated last, there is not a correctness problem + // but the space for the bit_mask is not freed. + assert(_resource_allocate_bit_mask, "Trying to free C heap space"); + if (mask_size() > small_mask_limit) { + FREE_RESOURCE_ARRAY(uintptr_t, _bit_mask[0], mask_word_size()); + } +} + +bool InterpreterOopMap::is_empty() { + bool result = _method == NULL; + assert(_method != NULL || (_bci == 0 && + (_mask_size == 0 || _mask_size == USHRT_MAX) && + _bit_mask[0] == 0), "Should be completely empty"); + return result; +} + +void InterpreterOopMap::initialize() { + _method = NULL; + _mask_size = USHRT_MAX; // This value should cause a failure quickly + _bci = 0; + _expression_stack_size = 0; + for (int i = 0; i < N; i++) _bit_mask[i] = 0; +} + +void InterpreterOopMap::iterate_oop(OffsetClosure* oop_closure) { + int n = number_of_entries(); + int word_index = 0; + uintptr_t value = 0; + uintptr_t mask = 0; + // iterate over entries + for (int i = 0; i < n; i++, mask <<= bits_per_entry) { + // get current word + if (mask == 0) { + value = bit_mask()[word_index++]; + mask = 1; + } + // test for oop + if ((value & (mask << oop_bit_number)) != 0) oop_closure->offset_do(i); + } +} + + +#ifdef ENABLE_ZAP_DEAD_LOCALS + +void InterpreterOopMap::iterate_all(OffsetClosure* oop_closure, OffsetClosure* value_closure, OffsetClosure* dead_closure) { + int n = number_of_entries(); + int word_index = 0; + uintptr_t value = 0; + uintptr_t mask = 0; + // iterate over entries + for (int i = 0; i < n; i++, mask <<= bits_per_entry) { + // get current word + if (mask == 0) { + value = bit_mask()[word_index++]; + mask = 1; + } + // test for dead values & oops, and for live values + if ((value & (mask << dead_bit_number)) != 0) dead_closure->offset_do(i); // call this for all dead values or oops + else if ((value & (mask << oop_bit_number)) != 0) oop_closure->offset_do(i); // call this for all live oops + else value_closure->offset_do(i); // call this for all live values + } +} + +#endif + + +void InterpreterOopMap::print() { + int n = number_of_entries(); + tty->print("oop map for "); + method()->print_value(); + tty->print(" @ %d = [%d] { ", bci(), n); + for (int i = 0; i < n; i++) { +#ifdef ENABLE_ZAP_DEAD_LOCALS + if (is_dead(i)) tty->print("%d+ ", i); + else +#endif + if (is_oop(i)) tty->print("%d ", i); + } + tty->print_cr("}"); +} + +class MaskFillerForNative: public NativeSignatureIterator { + private: + uintptr_t * _mask; // the bit mask to be filled + int _size; // the mask size in bits + + void set_one(int i) { + i *= InterpreterOopMap::bits_per_entry; + assert(0 <= i && i < _size, "offset out of bounds"); + _mask[i / BitsPerWord] |= (((uintptr_t) 1 << InterpreterOopMap::oop_bit_number) << (i % BitsPerWord)); + } + + public: + void pass_int() { /* ignore */ } + void pass_long() { /* ignore */ } + void pass_float() { /* ignore */ } + void pass_double() { /* ignore */ } + void pass_object() { set_one(offset()); } + + MaskFillerForNative(methodHandle method, uintptr_t* mask, int size) : NativeSignatureIterator(method) { + _mask = mask; + _size = size; + // initialize with 0 + int i = (size + BitsPerWord - 1) / BitsPerWord; + while (i-- > 0) _mask[i] = 0; + } + + void generate() { + NativeSignatureIterator::iterate(); + } +}; + +bool OopMapCacheEntry::verify_mask(CellTypeState* vars, CellTypeState* stack, int max_locals, int stack_top) { + // Check mask includes map + VerifyClosure blk(this); + iterate_oop(&blk); + if (blk.failed()) return false; + + // Check if map is generated correctly + // (Use ?: operator to make sure all 'true' & 'false' are represented exactly the same so we can use == afterwards) + if (TraceOopMapGeneration && Verbose) tty->print("Locals (%d): ", max_locals); + + for(int i = 0; i < max_locals; i++) { + bool v1 = is_oop(i) ? true : false; + bool v2 = vars[i].is_reference() ? true : false; + assert(v1 == v2, "locals oop mask generation error"); + if (TraceOopMapGeneration && Verbose) tty->print("%d", v1 ? 1 : 0); +#ifdef ENABLE_ZAP_DEAD_LOCALS + bool v3 = is_dead(i) ? true : false; + bool v4 = !vars[i].is_live() ? true : false; + assert(v3 == v4, "locals live mask generation error"); + assert(!(v1 && v3), "dead value marked as oop"); +#endif + } + + if (TraceOopMapGeneration && Verbose) { tty->cr(); tty->print("Stack (%d): ", stack_top); } + for(int j = 0; j < stack_top; j++) { + bool v1 = is_oop(max_locals + j) ? true : false; + bool v2 = stack[j].is_reference() ? true : false; + assert(v1 == v2, "stack oop mask generation error"); + if (TraceOopMapGeneration && Verbose) tty->print("%d", v1 ? 1 : 0); +#ifdef ENABLE_ZAP_DEAD_LOCALS + bool v3 = is_dead(max_locals + j) ? true : false; + bool v4 = !stack[j].is_live() ? true : false; + assert(v3 == v4, "stack live mask generation error"); + assert(!(v1 && v3), "dead value marked as oop"); +#endif + } + if (TraceOopMapGeneration && Verbose) tty->cr(); + return true; +} + +void OopMapCacheEntry::allocate_bit_mask() { + if (mask_size() > small_mask_limit) { + assert(_bit_mask[0] == 0, "bit mask should be new or just flushed"); + _bit_mask[0] = (intptr_t) + NEW_C_HEAP_ARRAY(uintptr_t, mask_word_size(), mtClass); + } +} + +void OopMapCacheEntry::deallocate_bit_mask() { + if (mask_size() > small_mask_limit && _bit_mask[0] != 0) { + assert(!Thread::current()->resource_area()->contains((void*)_bit_mask[0]), + "This bit mask should not be in the resource area"); + FREE_C_HEAP_ARRAY(uintptr_t, _bit_mask[0], mtClass); + debug_only(_bit_mask[0] = 0;) + } +} + + +void OopMapCacheEntry::fill_for_native(methodHandle mh) { + assert(mh->is_native(), "method must be native method"); + set_mask_size(mh->size_of_parameters() * bits_per_entry); + allocate_bit_mask(); + // fill mask for parameters + MaskFillerForNative mf(mh, bit_mask(), mask_size()); + mf.generate(); +} + + +void OopMapCacheEntry::fill(methodHandle method, int bci) { + HandleMark hm; + // Flush entry to deallocate an existing entry + flush(); + set_method(method()); + set_bci(bci); + if (method->is_native()) { + // Native method activations have oops only among the parameters and one + // extra oop following the parameters (the mirror for static native methods). + fill_for_native(method); + } else { + EXCEPTION_MARK; + OopMapForCacheEntry gen(method, bci, this); + gen.compute_map(CATCH); + } +} + + +void OopMapCacheEntry::set_mask(CellTypeState *vars, CellTypeState *stack, int stack_top) { + // compute bit mask size + int max_locals = method()->max_locals(); + int n_entries = max_locals + stack_top; + set_mask_size(n_entries * bits_per_entry); + allocate_bit_mask(); + set_expression_stack_size(stack_top); + + // compute bits + int word_index = 0; + uintptr_t value = 0; + uintptr_t mask = 1; + + CellTypeState* cell = vars; + for (int entry_index = 0; entry_index < n_entries; entry_index++, mask <<= bits_per_entry, cell++) { + // store last word + if (mask == 0) { + bit_mask()[word_index++] = value; + value = 0; + mask = 1; + } + + // switch to stack when done with locals + if (entry_index == max_locals) { + cell = stack; + } + + // set oop bit + if ( cell->is_reference()) { + value |= (mask << oop_bit_number ); + } + + #ifdef ENABLE_ZAP_DEAD_LOCALS + // set dead bit + if (!cell->is_live()) { + value |= (mask << dead_bit_number); + assert(!cell->is_reference(), "dead value marked as oop"); + } + #endif + } + + // make sure last word is stored + bit_mask()[word_index] = value; + + // verify bit mask + assert(verify_mask(vars, stack, max_locals, stack_top), "mask could not be verified"); + + +} + +void OopMapCacheEntry::flush() { + deallocate_bit_mask(); + initialize(); +} + + +// Implementation of OopMapCache + +#ifndef PRODUCT + +static long _total_memory_usage = 0; + +long OopMapCache::memory_usage() { + return _total_memory_usage; +} + +#endif + +void InterpreterOopMap::resource_copy(OopMapCacheEntry* from) { + assert(_resource_allocate_bit_mask, + "Should not resource allocate the _bit_mask"); + + set_method(from->method()); + set_bci(from->bci()); + set_mask_size(from->mask_size()); + set_expression_stack_size(from->expression_stack_size()); + + // Is the bit mask contained in the entry? + if (from->mask_size() <= small_mask_limit) { + memcpy((void *)_bit_mask, (void *)from->_bit_mask, + mask_word_size() * BytesPerWord); + } else { + // The expectation is that this InterpreterOopMap is a recently created + // and empty. It is used to get a copy of a cached entry. + // If the bit mask has a value, it should be in the + // resource area. + assert(_bit_mask[0] == 0 || + Thread::current()->resource_area()->contains((void*)_bit_mask[0]), + "The bit mask should have been allocated from a resource area"); + // Allocate the bit_mask from a Resource area for performance. Allocating + // from the C heap as is done for OopMapCache has a significant + // performance impact. + _bit_mask[0] = (uintptr_t) NEW_RESOURCE_ARRAY(uintptr_t, mask_word_size()); + assert(_bit_mask[0] != 0, "bit mask was not allocated"); + memcpy((void*) _bit_mask[0], (void*) from->_bit_mask[0], + mask_word_size() * BytesPerWord); + } +} + +inline unsigned int OopMapCache::hash_value_for(methodHandle method, int bci) { + // We use method->code_size() rather than method->identity_hash() below since + // the mark may not be present if a pointer to the method is already reversed. + return ((unsigned int) bci) + ^ ((unsigned int) method->max_locals() << 2) + ^ ((unsigned int) method->code_size() << 4) + ^ ((unsigned int) method->size_of_parameters() << 6); +} + + +OopMapCache::OopMapCache() : + _mut(Mutex::leaf, "An OopMapCache lock", true) +{ + _array = NEW_C_HEAP_ARRAY(OopMapCacheEntry, _size, mtClass); + // Cannot call flush for initialization, since flush + // will check if memory should be deallocated + for(int i = 0; i < _size; i++) _array[i].initialize(); + NOT_PRODUCT(_total_memory_usage += sizeof(OopMapCache) + (sizeof(OopMapCacheEntry) * _size);) +} + + +OopMapCache::~OopMapCache() { + assert(_array != NULL, "sanity check"); + // Deallocate oop maps that are allocated out-of-line + flush(); + // Deallocate array + NOT_PRODUCT(_total_memory_usage -= sizeof(OopMapCache) + (sizeof(OopMapCacheEntry) * _size);) + FREE_C_HEAP_ARRAY(OopMapCacheEntry, _array, mtClass); +} + +OopMapCacheEntry* OopMapCache::entry_at(int i) const { + return &_array[i % _size]; +} + +void OopMapCache::flush() { + for (int i = 0; i < _size; i++) _array[i].flush(); +} + +void OopMapCache::flush_obsolete_entries() { + for (int i = 0; i < _size; i++) + if (!_array[i].is_empty() && _array[i].method()->is_old()) { + // Cache entry is occupied by an old redefined method and we don't want + // to pin it down so flush the entry. + RC_TRACE(0x08000000, ("flush: %s(%s): cached entry @%d", + _array[i].method()->name()->as_C_string(), + _array[i].method()->signature()->as_C_string(), i)); + + _array[i].flush(); + } +} + +void OopMapCache::lookup(methodHandle method, + int bci, + InterpreterOopMap* entry_for) { + MutexLocker x(&_mut); + + OopMapCacheEntry* entry = NULL; + int probe = hash_value_for(method, bci); + + // Search hashtable for match + int i; + for(i = 0; i < _probe_depth; i++) { + entry = entry_at(probe + i); + if (entry->match(method, bci)) { + entry_for->resource_copy(entry); + assert(!entry_for->is_empty(), "A non-empty oop map should be returned"); + return; + } + } + + if (TraceOopMapGeneration) { + static int count = 0; + ResourceMark rm; + tty->print("%d - Computing oopmap at bci %d for ", ++count, bci); + method->print_value(); tty->cr(); + } + + // Entry is not in hashtable. + // Compute entry and return it + + if (method->should_not_be_cached()) { + // It is either not safe or not a good idea to cache this Method* + // at this time. We give the caller of lookup() a copy of the + // interesting info via parameter entry_for, but we don't add it to + // the cache. See the gory details in Method*.cpp. + compute_one_oop_map(method, bci, entry_for); + return; + } + + // First search for an empty slot + for(i = 0; i < _probe_depth; i++) { + entry = entry_at(probe + i); + if (entry->is_empty()) { + entry->fill(method, bci); + entry_for->resource_copy(entry); + assert(!entry_for->is_empty(), "A non-empty oop map should be returned"); + return; + } + } + + if (TraceOopMapGeneration) { + ResourceMark rm; + tty->print_cr("*** collision in oopmap cache - flushing item ***"); + } + + // No empty slot (uncommon case). Use (some approximation of a) LRU algorithm + //entry_at(probe + _probe_depth - 1)->flush(); + //for(i = _probe_depth - 1; i > 0; i--) { + // // Coping entry[i] = entry[i-1]; + // OopMapCacheEntry *to = entry_at(probe + i); + // OopMapCacheEntry *from = entry_at(probe + i - 1); + // to->copy(from); + // } + + assert(method->is_method(), "gaga"); + + entry = entry_at(probe + 0); + entry->fill(method, bci); + + // Copy the newly cached entry to input parameter + entry_for->resource_copy(entry); + + if (TraceOopMapGeneration) { + ResourceMark rm; + tty->print("Done with "); + method->print_value(); tty->cr(); + } + assert(!entry_for->is_empty(), "A non-empty oop map should be returned"); + + return; +} + +void OopMapCache::compute_one_oop_map(methodHandle method, int bci, InterpreterOopMap* entry) { + // Due to the invariants above it's tricky to allocate a temporary OopMapCacheEntry on the stack + OopMapCacheEntry* tmp = NEW_C_HEAP_ARRAY(OopMapCacheEntry, 1, mtClass); + tmp->initialize(); + tmp->fill(method, bci); + entry->resource_copy(tmp); + FREE_C_HEAP_ARRAY(OopMapCacheEntry, tmp, mtInternal); +}