/* * Copyright (c) 1998, 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 "precompiled.hpp" #include "code/codeBlob.hpp" #include "code/codeCache.hpp" #include "code/nmethod.hpp" #include "code/scopeDesc.hpp" #include "compiler/oopMap.hpp" #include "gc_interface/collectedHeap.hpp" #include "memory/allocation.inline.hpp" #include "memory/resourceArea.hpp" #include "runtime/frame.inline.hpp" #include "runtime/signature.hpp" #ifdef COMPILER1 #include "c1/c1_Defs.hpp" #endif // OopMapStream OopMapStream::OopMapStream(OopMap* oop_map) { if(oop_map->omv_data() == NULL) { _stream = new CompressedReadStream(oop_map->write_stream()->buffer()); } else { _stream = new CompressedReadStream(oop_map->omv_data()); } _mask = OopMapValue::type_mask_in_place; _size = oop_map->omv_count(); _position = 0; _valid_omv = false; } OopMapStream::OopMapStream(OopMap* oop_map, int oop_types_mask) { if(oop_map->omv_data() == NULL) { _stream = new CompressedReadStream(oop_map->write_stream()->buffer()); } else { _stream = new CompressedReadStream(oop_map->omv_data()); } _mask = oop_types_mask; _size = oop_map->omv_count(); _position = 0; _valid_omv = false; } void OopMapStream::find_next() { while(_position++ < _size) { _omv.read_from(_stream); if(((int)_omv.type() & _mask) > 0) { _valid_omv = true; return; } } _valid_omv = false; } // OopMap // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd // slots to hold 4-byte values like ints and floats in the LP64 build. OopMap::OopMap(int frame_size, int arg_count) { // OopMaps are usually quite so small, so pick a small initial size set_write_stream(new CompressedWriteStream(32)); set_omv_data(NULL); set_omv_count(0); #ifdef ASSERT _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count; _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length); for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value; #endif } OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) { // This constructor does a deep copy // of the source OopMap. set_write_stream(new CompressedWriteStream(source->omv_count() * 2)); set_omv_data(NULL); set_omv_count(0); set_offset(source->offset()); #ifdef ASSERT _locs_length = source->_locs_length; _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length); for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value; #endif // We need to copy the entries too. for (OopMapStream oms(source); !oms.is_done(); oms.next()) { OopMapValue omv = oms.current(); omv.write_on(write_stream()); increment_count(); } } OopMap* OopMap::deep_copy() { return new OopMap(_deep_copy_token, this); } void OopMap::copy_to(address addr) { memcpy(addr,this,sizeof(OopMap)); memcpy(addr + sizeof(OopMap),write_stream()->buffer(),write_stream()->position()); OopMap* new_oop = (OopMap*)addr; new_oop->set_omv_data_size(write_stream()->position()); new_oop->set_omv_data((unsigned char *)(addr + sizeof(OopMap))); new_oop->set_write_stream(NULL); } int OopMap::heap_size() const { int size = sizeof(OopMap); int align = sizeof(void *) - 1; if(write_stream() != NULL) { size += write_stream()->position(); } else { size += omv_data_size(); } // Align to a reasonable ending point size = ((size+align) & ~align); return size; } // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd // slots to hold 4-byte values like ints and floats in the LP64 build. void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) { assert(reg->value() < _locs_length, "too big reg value for stack size"); assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" ); debug_only( _locs_used[reg->value()] = x; ) OopMapValue o(reg, x); if(x == OopMapValue::callee_saved_value) { // This can never be a stack location, so we don't need to transform it. assert(optional->is_reg(), "Trying to callee save a stack location"); o.set_content_reg(optional); } else if(x == OopMapValue::derived_oop_value) { o.set_content_reg(optional); } o.write_on(write_stream()); increment_count(); } void OopMap::set_oop(VMReg reg) { set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad()); } void OopMap::set_value(VMReg reg) { // At this time, we only need value entries in our OopMap when ZapDeadCompiledLocals is active. if (ZapDeadCompiledLocals) set_xxx(reg, OopMapValue::value_value, VMRegImpl::Bad()); } void OopMap::set_narrowoop(VMReg reg) { set_xxx(reg, OopMapValue::narrowoop_value, VMRegImpl::Bad()); } void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) { set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register); } void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) { if( reg == derived_from_local_register ) { // Actually an oop, derived shares storage with base, set_oop(reg); } else { set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register); } } // OopMapSet OopMapSet::OopMapSet() { set_om_size(MinOopMapAllocation); set_om_count(0); OopMap** temp = NEW_RESOURCE_ARRAY(OopMap*, om_size()); set_om_data(temp); } void OopMapSet::grow_om_data() { int new_size = om_size() * 2; OopMap** new_data = NEW_RESOURCE_ARRAY(OopMap*, new_size); memcpy(new_data,om_data(),om_size() * sizeof(OopMap*)); set_om_size(new_size); set_om_data(new_data); } void OopMapSet::copy_to(address addr) { address temp = addr; int align = sizeof(void *) - 1; // Copy this memcpy(addr,this,sizeof(OopMapSet)); temp += sizeof(OopMapSet); temp = (address)((intptr_t)(temp + align) & ~align); // Do the needed fixups to the new OopMapSet OopMapSet* new_set = (OopMapSet*)addr; new_set->set_om_data((OopMap**)temp); // Allow enough space for the OopMap pointers temp += (om_count() * sizeof(OopMap*)); for(int i=0; i < om_count(); i++) { OopMap* map = at(i); map->copy_to((address)temp); new_set->set(i,(OopMap*)temp); temp += map->heap_size(); } // This "locks" the OopMapSet new_set->set_om_size(-1); } void OopMapSet::add_gc_map(int pc_offset, OopMap *map ) { assert(om_size() != -1,"Cannot grow a fixed OopMapSet"); if(om_count() >= om_size()) { grow_om_data(); } map->set_offset(pc_offset); #ifdef ASSERT if(om_count() > 0) { OopMap* last = at(om_count()-1); if (last->offset() == map->offset() ) { fatal("OopMap inserted twice"); } if(last->offset() > map->offset()) { tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d", om_count(),last->offset(),om_count()+1,map->offset()); } } #endif // ASSERT set(om_count(),map); increment_count(); } int OopMapSet::heap_size() const { // The space we use int size = sizeof(OopMap); int align = sizeof(void *) - 1; size = ((size+align) & ~align); size += om_count() * sizeof(OopMap*); // Now add in the space needed for the indivdiual OopMaps for(int i=0; i < om_count(); i++) { size += at(i)->heap_size(); } // We don't need to align this, it will be naturally pointer aligned return size; } OopMap* OopMapSet::singular_oop_map() { guarantee(om_count() == 1, "Make sure we only have a single gc point"); return at(0); } OopMap* OopMapSet::find_map_at_offset(int pc_offset) const { int i, len = om_count(); assert( len > 0, "must have pointer maps" ); // Scan through oopmaps. Stop when current offset is either equal or greater // than the one we are looking for. for( i = 0; i < len; i++) { if( at(i)->offset() >= pc_offset ) break; } assert( i < len, "oopmap not found" ); OopMap* m = at(i); assert( m->offset() == pc_offset, "oopmap not found" ); return m; } class DoNothingClosure: public OopClosure { public: void do_oop(oop* p) {} void do_oop(narrowOop* p) {} }; static DoNothingClosure do_nothing; static void add_derived_oop(oop* base, oop* derived) { #ifndef TIERED COMPILER1_PRESENT(ShouldNotReachHere();) #endif // TIERED #ifdef COMPILER2 DerivedPointerTable::add(derived, base); #endif // COMPILER2 } #ifndef PRODUCT static void trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) { // Print oopmap and regmap tty->print_cr("------ "); CodeBlob* cb = fr->cb(); OopMapSet* maps = cb->oop_maps(); OopMap* map = cb->oop_map_for_return_address(fr->pc()); map->print(); if( cb->is_nmethod() ) { nmethod* nm = (nmethod*)cb; // native wrappers have no scope data, it is implied if (nm->is_native_method()) { tty->print("bci: 0 (native)"); } else { ScopeDesc* scope = nm->scope_desc_at(fr->pc()); tty->print("bci: %d ",scope->bci()); } } tty->cr(); fr->print_on(tty); tty->print(" "); cb->print_value_on(tty); tty->cr(); reg_map->print(); tty->print_cr("------ "); } #endif // PRODUCT void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f) { // add derived oops to a table all_do(fr, reg_map, f, add_derived_oop, &do_nothing); } void OopMapSet::all_do(const frame *fr, const RegisterMap *reg_map, OopClosure* oop_fn, void derived_oop_fn(oop*, oop*), OopClosure* value_fn) { CodeBlob* cb = fr->cb(); assert(cb != NULL, "no codeblob"); NOT_PRODUCT(if (TraceCodeBlobStacks) trace_codeblob_maps(fr, reg_map);) OopMapSet* maps = cb->oop_maps(); OopMap* map = cb->oop_map_for_return_address(fr->pc()); assert(map != NULL, "no ptr map found"); // handle derived pointers first (otherwise base pointer may be // changed before derived pointer offset has been collected) OopMapValue omv; { OopMapStream oms(map,OopMapValue::derived_oop_value); if (!oms.is_done()) { #ifndef TIERED COMPILER1_PRESENT(ShouldNotReachHere();) #endif // !TIERED // Protect the operation on the derived pointers. This // protects the addition of derived pointers to the shared // derived pointer table in DerivedPointerTable::add(). MutexLockerEx x(DerivedPointerTableGC_lock, Mutex::_no_safepoint_check_flag); do { omv = oms.current(); oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map); if ( loc != NULL ) { oop *base_loc = fr->oopmapreg_to_location(omv.content_reg(), reg_map); oop *derived_loc = loc; oop val = *base_loc; if (val == (oop)NULL || Universe::is_narrow_oop_base(val)) { // Ignore NULL oops and decoded NULL narrow oops which // equal to Universe::narrow_oop_base when a narrow oop // implicit null check is used in compiled code. // The narrow_oop_base could be NULL or be the address // of the page below heap depending on compressed oops mode. } else derived_oop_fn(base_loc, derived_loc); } oms.next(); } while (!oms.is_done()); } } // We want coop, value and oop oop_types int mask = OopMapValue::oop_value | OopMapValue::value_value | OopMapValue::narrowoop_value; { for (OopMapStream oms(map,mask); !oms.is_done(); oms.next()) { omv = oms.current(); oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map); if ( loc != NULL ) { if ( omv.type() == OopMapValue::oop_value ) { oop val = *loc; if (val == (oop)NULL || Universe::is_narrow_oop_base(val)) { // Ignore NULL oops and decoded NULL narrow oops which // equal to Universe::narrow_oop_base when a narrow oop // implicit null check is used in compiled code. // The narrow_oop_base could be NULL or be the address // of the page below heap depending on compressed oops mode. continue; } #ifdef ASSERT if ((((uintptr_t)loc & (sizeof(*loc)-1)) != 0) || !Universe::heap()->is_in_or_null(*loc)) { tty->print_cr("# Found non oop pointer. Dumping state at failure"); // try to dump out some helpful debugging information trace_codeblob_maps(fr, reg_map); omv.print(); tty->print_cr("register r"); omv.reg()->print(); tty->print_cr("loc = %p *loc = %p\n", loc, (address)*loc); // do the real assert. assert(Universe::heap()->is_in_or_null(*loc), "found non oop pointer"); } #endif // ASSERT oop_fn->do_oop(loc); } else if ( omv.type() == OopMapValue::value_value ) { assert((*loc) == (oop)NULL || !Universe::is_narrow_oop_base(*loc), "found invalid value pointer"); value_fn->do_oop(loc); } else if ( omv.type() == OopMapValue::narrowoop_value ) { narrowOop *nl = (narrowOop*)loc; #ifndef VM_LITTLE_ENDIAN if (!omv.reg()->is_stack()) { // compressed oops in registers only take up 4 bytes of an // 8 byte register but they are in the wrong part of the // word so adjust loc to point at the right place. nl = (narrowOop*)((address)nl + 4); } #endif oop_fn->do_oop(nl); } } } } } // Update callee-saved register info for the following frame void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) { ResourceMark rm; CodeBlob* cb = fr->cb(); assert(cb != NULL, "no codeblob"); // Any reg might be saved by a safepoint handler (see generate_handler_blob). const int max_saved_on_entry_reg_count = ConcreteRegisterImpl::number_of_registers; assert( reg_map->_update_for_id == NULL || fr->is_older(reg_map->_update_for_id), "already updated this map; do not 'update' it twice!" ); debug_only(reg_map->_update_for_id = fr->id()); // Check if caller must update oop argument assert((reg_map->include_argument_oops() || !cb->caller_must_gc_arguments(reg_map->thread())), "include_argument_oops should already be set"); int nof_callee = 0; oop* locs[2*max_saved_on_entry_reg_count+1]; VMReg regs[2*max_saved_on_entry_reg_count+1]; // ("+1" because max_saved_on_entry_reg_count might be zero) // Scan through oopmap and find location of all callee-saved registers // (we do not do update in place, since info could be overwritten) address pc = fr->pc(); OopMap* map = cb->oop_map_for_return_address(pc); assert(map != NULL, " no ptr map found"); OopMapValue omv; for(OopMapStream oms(map,OopMapValue::callee_saved_value); !oms.is_done(); oms.next()) { omv = oms.current(); assert(nof_callee < 2*max_saved_on_entry_reg_count, "overflow"); regs[nof_callee] = omv.content_reg(); locs[nof_callee] = fr->oopmapreg_to_location(omv.reg(),reg_map); nof_callee++; } // Check that runtime stubs save all callee-saved registers #ifdef COMPILER2 assert(cb->is_compiled_by_c1() || !cb->is_runtime_stub() || (nof_callee >= SAVED_ON_ENTRY_REG_COUNT || nof_callee >= C_SAVED_ON_ENTRY_REG_COUNT), "must save all"); #endif // COMPILER2 // Copy found callee-saved register to reg_map for(int i = 0; i < nof_callee; i++) { reg_map->set_location(regs[i], (address)locs[i]); } } //============================================================================= // Non-Product code #ifndef PRODUCT bool OopMap::has_derived_pointer() const { #ifndef TIERED COMPILER1_PRESENT(return false); #endif // !TIERED #ifdef COMPILER2 OopMapStream oms((OopMap*)this,OopMapValue::derived_oop_value); return oms.is_done(); #else return false; #endif // COMPILER2 } #endif //PRODUCT // Printing code is present in product build for -XX:+PrintAssembly. static void print_register_type(OopMapValue::oop_types x, VMReg optional, outputStream* st) { switch( x ) { case OopMapValue::oop_value: st->print("Oop"); break; case OopMapValue::value_value: st->print("Value" ); break; case OopMapValue::narrowoop_value: tty->print("NarrowOop" ); break; case OopMapValue::callee_saved_value: st->print("Callers_" ); optional->print_on(st); break; case OopMapValue::derived_oop_value: st->print("Derived_oop_" ); optional->print_on(st); break; default: ShouldNotReachHere(); } } void OopMapValue::print_on(outputStream* st) const { reg()->print_on(st); st->print("="); print_register_type(type(),content_reg(),st); st->print(" "); } void OopMap::print_on(outputStream* st) const { OopMapValue omv; st->print("OopMap{"); for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) { omv = oms.current(); omv.print_on(st); } st->print("off=%d}", (int) offset()); } void OopMapSet::print_on(outputStream* st) const { int i, len = om_count(); st->print_cr("OopMapSet contains %d OopMaps\n",len); for( i = 0; i < len; i++) { OopMap* m = at(i); st->print_cr("#%d ",i); m->print_on(st); st->cr(); } } //------------------------------DerivedPointerTable--------------------------- #ifdef COMPILER2 class DerivedPointerEntry : public CHeapObj { private: oop* _location; // Location of derived pointer (also pointing to the base) intptr_t _offset; // Offset from base pointer public: DerivedPointerEntry(oop* location, intptr_t offset) { _location = location; _offset = offset; } oop* location() { return _location; } intptr_t offset() { return _offset; } }; GrowableArray* DerivedPointerTable::_list = NULL; bool DerivedPointerTable::_active = false; void DerivedPointerTable::clear() { // The first time, we create the list. Otherwise it should be // empty. If not, then we have probably forgotton to call // update_pointers after last GC/Scavenge. assert (!_active, "should not be active"); assert(_list == NULL || _list->length() == 0, "table not empty"); if (_list == NULL) { _list = new (ResourceObj::C_HEAP) GrowableArray(10, true); // Allocated on C heap } _active = true; } // Returns value of location as an int intptr_t value_of_loc(oop *pointer) { return (intptr_t)(*pointer); } void DerivedPointerTable::add(oop *derived_loc, oop *base_loc) { assert(Universe::heap()->is_in_or_null(*base_loc), "not an oop"); assert(derived_loc != base_loc, "Base and derived in same location"); if (_active) { assert(*derived_loc != (oop)base_loc, "location already added"); assert(_list != NULL, "list must exist"); intptr_t offset = value_of_loc(derived_loc) - value_of_loc(base_loc); assert(offset >= -1000000, "wrong derived pointer info"); if (TraceDerivedPointers) { tty->print_cr( "Add derived pointer@" INTPTR_FORMAT " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: %d)", derived_loc, (address)*derived_loc, (address)*base_loc, base_loc, offset ); } // Set derived oop location to point to base. *derived_loc = (oop)base_loc; assert_lock_strong(DerivedPointerTableGC_lock); DerivedPointerEntry *entry = new DerivedPointerEntry(derived_loc, offset); _list->append(entry); } } void DerivedPointerTable::update_pointers() { assert(_list != NULL, "list must exist"); for(int i = 0; i < _list->length(); i++) { DerivedPointerEntry* entry = _list->at(i); oop* derived_loc = entry->location(); intptr_t offset = entry->offset(); // The derived oop was setup to point to location of base oop base = **(oop**)derived_loc; assert(Universe::heap()->is_in_or_null(base), "must be an oop"); *derived_loc = (oop)(((address)base) + offset); assert(value_of_loc(derived_loc) - value_of_loc(&base) == offset, "sanity check"); if (TraceDerivedPointers) { tty->print_cr("Updating derived pointer@" INTPTR_FORMAT " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: %d)", derived_loc, (address)*derived_loc, (address)base, offset); } // Delete entry delete entry; _list->at_put(i, NULL); } // Clear list, so it is ready for next traversal (this is an invariant) if (TraceDerivedPointers && !_list->is_empty()) { tty->print_cr("--------------------------"); } _list->clear(); _active = false; } #endif // COMPILER2