/* * Copyright (c) 2018, 2019, Red Hat, Inc. All rights reserved. * * 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 "gc/shared/barrierSet.hpp" #include "gc/shenandoah/shenandoahHeap.hpp" #include "gc/shenandoah/shenandoahHeuristics.hpp" #include "gc/shenandoah/shenandoahRuntime.hpp" #include "gc/shenandoah/shenandoahThreadLocalData.hpp" #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp" #include "gc/shenandoah/c2/shenandoahSupport.hpp" #include "opto/arraycopynode.hpp" #include "opto/escape.hpp" #include "opto/graphKit.hpp" #include "opto/idealKit.hpp" #include "opto/macro.hpp" #include "opto/movenode.hpp" #include "opto/narrowptrnode.hpp" #include "opto/rootnode.hpp" ShenandoahBarrierSetC2* ShenandoahBarrierSetC2::bsc2() { return reinterpret_cast(BarrierSet::barrier_set()->barrier_set_c2()); } ShenandoahBarrierSetC2State::ShenandoahBarrierSetC2State(Arena* comp_arena) : _shenandoah_barriers(new (comp_arena) GrowableArray(comp_arena, 8, 0, NULL)) { } int ShenandoahBarrierSetC2State::shenandoah_barriers_count() const { return _shenandoah_barriers->length(); } ShenandoahWriteBarrierNode* ShenandoahBarrierSetC2State::shenandoah_barrier(int idx) const { return _shenandoah_barriers->at(idx); } void ShenandoahBarrierSetC2State::add_shenandoah_barrier(ShenandoahWriteBarrierNode * n) { assert(!_shenandoah_barriers->contains(n), "duplicate entry in barrier list"); _shenandoah_barriers->append(n); } void ShenandoahBarrierSetC2State::remove_shenandoah_barrier(ShenandoahWriteBarrierNode * n) { if (_shenandoah_barriers->contains(n)) { _shenandoah_barriers->remove(n); } } #define __ kit-> Node* ShenandoahBarrierSetC2::shenandoah_read_barrier(GraphKit* kit, Node* obj) const { if (ShenandoahReadBarrier) { obj = shenandoah_read_barrier_impl(kit, obj, false, true, true); } return obj; } Node* ShenandoahBarrierSetC2::shenandoah_storeval_barrier(GraphKit* kit, Node* obj) const { if (ShenandoahStoreValEnqueueBarrier) { obj = shenandoah_write_barrier(kit, obj); obj = shenandoah_enqueue_barrier(kit, obj); } if (ShenandoahStoreValReadBarrier) { obj = shenandoah_read_barrier_impl(kit, obj, true, false, false); } return obj; } Node* ShenandoahBarrierSetC2::shenandoah_read_barrier_impl(GraphKit* kit, Node* obj, bool use_ctrl, bool use_mem, bool allow_fromspace) const { const Type* obj_type = obj->bottom_type(); if (obj_type->higher_equal(TypePtr::NULL_PTR)) { return obj; } const TypePtr* adr_type = ShenandoahBarrierNode::brooks_pointer_type(obj_type); Node* mem = use_mem ? __ memory(adr_type) : __ immutable_memory(); if (! ShenandoahBarrierNode::needs_barrier(&__ gvn(), NULL, obj, mem, allow_fromspace)) { // We know it is null, no barrier needed. return obj; } if (obj_type->meet(TypePtr::NULL_PTR) == obj_type->remove_speculative()) { // We don't know if it's null or not. Need null-check. enum { _not_null_path = 1, _null_path, PATH_LIMIT }; RegionNode* region = new RegionNode(PATH_LIMIT); Node* phi = new PhiNode(region, obj_type); Node* null_ctrl = __ top(); Node* not_null_obj = __ null_check_oop(obj, &null_ctrl); region->init_req(_null_path, null_ctrl); phi ->init_req(_null_path, __ zerocon(T_OBJECT)); Node* ctrl = use_ctrl ? __ control() : NULL; ShenandoahReadBarrierNode* rb = new ShenandoahReadBarrierNode(ctrl, mem, not_null_obj, allow_fromspace); Node* n = __ gvn().transform(rb); region->init_req(_not_null_path, __ control()); phi ->init_req(_not_null_path, n); __ set_control(__ gvn().transform(region)); __ record_for_igvn(region); return __ gvn().transform(phi); } else { // We know it is not null. Simple barrier is sufficient. Node* ctrl = use_ctrl ? __ control() : NULL; ShenandoahReadBarrierNode* rb = new ShenandoahReadBarrierNode(ctrl, mem, obj, allow_fromspace); Node* n = __ gvn().transform(rb); __ record_for_igvn(n); return n; } } Node* ShenandoahBarrierSetC2::shenandoah_write_barrier_helper(GraphKit* kit, Node* obj, const TypePtr* adr_type) const { ShenandoahWriteBarrierNode* wb = new ShenandoahWriteBarrierNode(kit->C, kit->control(), kit->memory(adr_type), obj); Node* n = __ gvn().transform(wb); if (n == wb) { // New barrier needs memory projection. Node* proj = __ gvn().transform(new ShenandoahWBMemProjNode(n)); __ set_memory(proj, adr_type); } return n; } Node* ShenandoahBarrierSetC2::shenandoah_write_barrier(GraphKit* kit, Node* obj) const { if (ShenandoahWriteBarrier) { obj = shenandoah_write_barrier_impl(kit, obj); } return obj; } Node* ShenandoahBarrierSetC2::shenandoah_write_barrier_impl(GraphKit* kit, Node* obj) const { if (! ShenandoahBarrierNode::needs_barrier(&__ gvn(), NULL, obj, NULL, true)) { return obj; } const Type* obj_type = obj->bottom_type(); const TypePtr* adr_type = ShenandoahBarrierNode::brooks_pointer_type(obj_type); Node* n = shenandoah_write_barrier_helper(kit, obj, adr_type); __ record_for_igvn(n); return n; } bool ShenandoahBarrierSetC2::satb_can_remove_pre_barrier(GraphKit* kit, PhaseTransform* phase, Node* adr, BasicType bt, uint adr_idx) const { intptr_t offset = 0; Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset); AllocateNode* alloc = AllocateNode::Ideal_allocation(base, phase); if (offset == Type::OffsetBot) { return false; // cannot unalias unless there are precise offsets } if (alloc == NULL) { return false; // No allocation found } intptr_t size_in_bytes = type2aelembytes(bt); Node* mem = __ memory(adr_idx); // start searching here... for (int cnt = 0; cnt < 50; cnt++) { if (mem->is_Store()) { Node* st_adr = mem->in(MemNode::Address); intptr_t st_offset = 0; Node* st_base = AddPNode::Ideal_base_and_offset(st_adr, phase, st_offset); if (st_base == NULL) { break; // inscrutable pointer } // Break we have found a store with same base and offset as ours so break if (st_base == base && st_offset == offset) { break; } if (st_offset != offset && st_offset != Type::OffsetBot) { const int MAX_STORE = BytesPerLong; if (st_offset >= offset + size_in_bytes || st_offset <= offset - MAX_STORE || st_offset <= offset - mem->as_Store()->memory_size()) { // Success: The offsets are provably independent. // (You may ask, why not just test st_offset != offset and be done? // The answer is that stores of different sizes can co-exist // in the same sequence of RawMem effects. We sometimes initialize // a whole 'tile' of array elements with a single jint or jlong.) mem = mem->in(MemNode::Memory); continue; // advance through independent store memory } } if (st_base != base && MemNode::detect_ptr_independence(base, alloc, st_base, AllocateNode::Ideal_allocation(st_base, phase), phase)) { // Success: The bases are provably independent. mem = mem->in(MemNode::Memory); continue; // advance through independent store memory } } else if (mem->is_Proj() && mem->in(0)->is_Initialize()) { InitializeNode* st_init = mem->in(0)->as_Initialize(); AllocateNode* st_alloc = st_init->allocation(); // Make sure that we are looking at the same allocation site. // The alloc variable is guaranteed to not be null here from earlier check. if (alloc == st_alloc) { // Check that the initialization is storing NULL so that no previous store // has been moved up and directly write a reference Node* captured_store = st_init->find_captured_store(offset, type2aelembytes(T_OBJECT), phase); if (captured_store == NULL || captured_store == st_init->zero_memory()) { return true; } } } // Unless there is an explicit 'continue', we must bail out here, // because 'mem' is an inscrutable memory state (e.g., a call). break; } return false; } #undef __ #define __ ideal. void ShenandoahBarrierSetC2::satb_write_barrier_pre(GraphKit* kit, bool do_load, Node* obj, Node* adr, uint alias_idx, Node* val, const TypeOopPtr* val_type, Node* pre_val, BasicType bt) const { // Some sanity checks // Note: val is unused in this routine. if (do_load) { // We need to generate the load of the previous value assert(obj != NULL, "must have a base"); assert(adr != NULL, "where are loading from?"); assert(pre_val == NULL, "loaded already?"); assert(val_type != NULL, "need a type"); if (ReduceInitialCardMarks && satb_can_remove_pre_barrier(kit, &kit->gvn(), adr, bt, alias_idx)) { return; } } else { // In this case both val_type and alias_idx are unused. assert(pre_val != NULL, "must be loaded already"); // Nothing to be done if pre_val is null. if (pre_val->bottom_type() == TypePtr::NULL_PTR) return; assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here"); } assert(bt == T_OBJECT, "or we shouldn't be here"); IdealKit ideal(kit, true); Node* tls = __ thread(); // ThreadLocalStorage Node* no_base = __ top(); Node* zero = __ ConI(0); Node* zeroX = __ ConX(0); float likely = PROB_LIKELY(0.999); float unlikely = PROB_UNLIKELY(0.999); // Offsets into the thread const int index_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()); const int buffer_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()); // Now the actual pointers into the thread Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset)); Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset)); // Now some of the values Node* marking; Node* gc_state = __ AddP(no_base, tls, __ ConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset()))); Node* ld = __ load(__ ctrl(), gc_state, TypeInt::BYTE, T_BYTE, Compile::AliasIdxRaw); marking = __ AndI(ld, __ ConI(ShenandoahHeap::MARKING)); assert(ShenandoahWriteBarrierNode::is_gc_state_load(ld), "Should match the shape"); // if (!marking) __ if_then(marking, BoolTest::ne, zero, unlikely); { BasicType index_bt = TypeX_X->basic_type(); assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 SATBMarkQueue::_index with wrong size."); Node* index = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw); if (do_load) { // load original value // alias_idx correct?? pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx); } // if (pre_val != NULL) __ if_then(pre_val, BoolTest::ne, kit->null()); { Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw); // is the queue for this thread full? __ if_then(index, BoolTest::ne, zeroX, likely); { // decrement the index Node* next_index = kit->gvn().transform(new SubXNode(index, __ ConX(sizeof(intptr_t)))); // Now get the buffer location we will log the previous value into and store it Node *log_addr = __ AddP(no_base, buffer, next_index); __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered); // update the index __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered); } __ else_(); { // logging buffer is full, call the runtime const TypeFunc *tf = ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type(); __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), "shenandoah_wb_pre", pre_val, tls); } __ end_if(); // (!index) } __ end_if(); // (pre_val != NULL) } __ end_if(); // (!marking) // Final sync IdealKit and GraphKit. kit->final_sync(ideal); if (ShenandoahSATBBarrier && adr != NULL) { Node* c = kit->control(); Node* call = c->in(1)->in(1)->in(1)->in(0); assert(is_shenandoah_wb_pre_call(call), "shenandoah_wb_pre call expected"); call->add_req(adr); } } bool ShenandoahBarrierSetC2::is_shenandoah_wb_pre_call(Node* call) { return call->is_CallLeaf() && call->as_CallLeaf()->entry_point() == CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry); } bool ShenandoahBarrierSetC2::is_shenandoah_wb_call(Node* call) { return call->is_CallLeaf() && call->as_CallLeaf()->entry_point() == CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_barrier_JRT); } bool ShenandoahBarrierSetC2::is_shenandoah_marking_if(PhaseTransform *phase, Node* n) { if (n->Opcode() != Op_If) { return false; } Node* bol = n->in(1); assert(bol->is_Bool(), ""); Node* cmpx = bol->in(1); if (bol->as_Bool()->_test._test == BoolTest::ne && cmpx->is_Cmp() && cmpx->in(2) == phase->intcon(0) && is_shenandoah_state_load(cmpx->in(1)->in(1)) && cmpx->in(1)->in(2)->is_Con() && cmpx->in(1)->in(2) == phase->intcon(ShenandoahHeap::MARKING)) { return true; } return false; } bool ShenandoahBarrierSetC2::is_shenandoah_state_load(Node* n) { if (!n->is_Load()) return false; const int state_offset = in_bytes(ShenandoahThreadLocalData::gc_state_offset()); return n->in(2)->is_AddP() && n->in(2)->in(2)->Opcode() == Op_ThreadLocal && n->in(2)->in(3)->is_Con() && n->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == state_offset; } void ShenandoahBarrierSetC2::shenandoah_write_barrier_pre(GraphKit* kit, bool do_load, Node* obj, Node* adr, uint alias_idx, Node* val, const TypeOopPtr* val_type, Node* pre_val, BasicType bt) const { if (ShenandoahSATBBarrier) { IdealKit ideal(kit); kit->sync_kit(ideal); satb_write_barrier_pre(kit, do_load, obj, adr, alias_idx, val, val_type, pre_val, bt); ideal.sync_kit(kit); kit->final_sync(ideal); } } Node* ShenandoahBarrierSetC2::shenandoah_enqueue_barrier(GraphKit* kit, Node* pre_val) const { return kit->gvn().transform(new ShenandoahEnqueueBarrierNode(pre_val)); } // Helper that guards and inserts a pre-barrier. void ShenandoahBarrierSetC2::insert_pre_barrier(GraphKit* kit, Node* base_oop, Node* offset, Node* pre_val, bool need_mem_bar) const { // We could be accessing the referent field of a reference object. If so, when G1 // is enabled, we need to log the value in the referent field in an SATB buffer. // This routine performs some compile time filters and generates suitable // runtime filters that guard the pre-barrier code. // Also add memory barrier for non volatile load from the referent field // to prevent commoning of loads across safepoint. // Some compile time checks. // If offset is a constant, is it java_lang_ref_Reference::_reference_offset? const TypeX* otype = offset->find_intptr_t_type(); if (otype != NULL && otype->is_con() && otype->get_con() != java_lang_ref_Reference::referent_offset) { // Constant offset but not the reference_offset so just return return; } // We only need to generate the runtime guards for instances. const TypeOopPtr* btype = base_oop->bottom_type()->isa_oopptr(); if (btype != NULL) { if (btype->isa_aryptr()) { // Array type so nothing to do return; } const TypeInstPtr* itype = btype->isa_instptr(); if (itype != NULL) { // Can the klass of base_oop be statically determined to be // _not_ a sub-class of Reference and _not_ Object? ciKlass* klass = itype->klass(); if ( klass->is_loaded() && !klass->is_subtype_of(kit->env()->Reference_klass()) && !kit->env()->Object_klass()->is_subtype_of(klass)) { return; } } } // The compile time filters did not reject base_oop/offset so // we need to generate the following runtime filters // // if (offset == java_lang_ref_Reference::_reference_offset) { // if (instance_of(base, java.lang.ref.Reference)) { // pre_barrier(_, pre_val, ...); // } // } float likely = PROB_LIKELY( 0.999); float unlikely = PROB_UNLIKELY(0.999); IdealKit ideal(kit); Node* referent_off = __ ConX(java_lang_ref_Reference::referent_offset); __ if_then(offset, BoolTest::eq, referent_off, unlikely); { // Update graphKit memory and control from IdealKit. kit->sync_kit(ideal); Node* ref_klass_con = kit->makecon(TypeKlassPtr::make(kit->env()->Reference_klass())); Node* is_instof = kit->gen_instanceof(base_oop, ref_klass_con); // Update IdealKit memory and control from graphKit. __ sync_kit(kit); Node* one = __ ConI(1); // is_instof == 0 if base_oop == NULL __ if_then(is_instof, BoolTest::eq, one, unlikely); { // Update graphKit from IdeakKit. kit->sync_kit(ideal); // Use the pre-barrier to record the value in the referent field satb_write_barrier_pre(kit, false /* do_load */, NULL /* obj */, NULL /* adr */, max_juint /* alias_idx */, NULL /* val */, NULL /* val_type */, pre_val /* pre_val */, T_OBJECT); if (need_mem_bar) { // Add memory barrier to prevent commoning reads from this field // across safepoint since GC can change its value. kit->insert_mem_bar(Op_MemBarCPUOrder); } // Update IdealKit from graphKit. __ sync_kit(kit); } __ end_if(); // _ref_type != ref_none } __ end_if(); // offset == referent_offset // Final sync IdealKit and GraphKit. kit->final_sync(ideal); } #undef __ const TypeFunc* ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type() { const Type **fields = TypeTuple::fields(2); fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL; // original field value fields[TypeFunc::Parms+1] = TypeRawPtr::NOTNULL; // thread const TypeTuple *domain = TypeTuple::make(TypeFunc::Parms+2, fields); // create result type (range) fields = TypeTuple::fields(0); const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+0, fields); return TypeFunc::make(domain, range); } const TypeFunc* ShenandoahBarrierSetC2::shenandoah_clone_barrier_Type() { const Type **fields = TypeTuple::fields(1); fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL; // original field value const TypeTuple *domain = TypeTuple::make(TypeFunc::Parms+1, fields); // create result type (range) fields = TypeTuple::fields(0); const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+0, fields); return TypeFunc::make(domain, range); } const TypeFunc* ShenandoahBarrierSetC2::shenandoah_write_barrier_Type() { const Type **fields = TypeTuple::fields(1); fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL; // original field value const TypeTuple *domain = TypeTuple::make(TypeFunc::Parms+1, fields); // create result type (range) fields = TypeTuple::fields(1); fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL; const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+1, fields); return TypeFunc::make(domain, range); } void ShenandoahBarrierSetC2::resolve_address(C2Access& access) const { const TypePtr* adr_type = access.addr().type(); if ((access.decorators() & IN_NATIVE) == 0 && (adr_type->isa_instptr() || adr_type->isa_aryptr())) { int off = adr_type->is_ptr()->offset(); int base_off = adr_type->isa_instptr() ? instanceOopDesc::base_offset_in_bytes() : arrayOopDesc::base_offset_in_bytes(adr_type->is_aryptr()->elem()->array_element_basic_type()); assert(off != Type::OffsetTop, "unexpected offset"); if (off == Type::OffsetBot || off >= base_off) { DecoratorSet decorators = access.decorators(); bool is_write = (decorators & C2_WRITE_ACCESS) != 0; GraphKit* kit = NULL; if (access.is_parse_access()) { C2ParseAccess& parse_access = static_cast(access); kit = parse_access.kit(); } Node* adr = access.addr().node(); assert(adr->is_AddP(), "unexpected address shape"); Node* base = adr->in(AddPNode::Base); if (is_write) { if (kit != NULL) { base = shenandoah_write_barrier(kit, base); } else { assert(access.is_opt_access(), "either parse or opt access"); assert((access.decorators() & C2_ARRAY_COPY) != 0, "can be skipped for clone"); } } else { if (adr_type->isa_instptr()) { Compile* C = access.gvn().C; ciField* field = C->alias_type(adr_type)->field(); // Insert read barrier for Shenandoah. if (field != NULL && ((ShenandoahOptimizeStaticFinals && field->is_static() && field->is_final()) || (ShenandoahOptimizeInstanceFinals && !field->is_static() && field->is_final()) || (ShenandoahOptimizeStableFinals && field->is_stable()))) { // Skip the barrier for special fields } else { if (kit != NULL) { base = shenandoah_read_barrier(kit, base); } else { assert(access.is_opt_access(), "either parse or opt access"); assert((access.decorators() & C2_ARRAY_COPY) != 0, "can be skipped for arraycopy"); } } } else { if (kit != NULL) { base = shenandoah_read_barrier(kit, base); } else { assert(access.is_opt_access(), "either parse or opt access"); assert((access.decorators() & C2_ARRAY_COPY) != 0, "can be skipped for arraycopy"); } } } if (base != adr->in(AddPNode::Base)) { assert(kit != NULL, "no barrier should have been added"); Node* address = adr->in(AddPNode::Address); if (address->is_AddP()) { assert(address->in(AddPNode::Base) == adr->in(AddPNode::Base), "unexpected address shape"); assert(!address->in(AddPNode::Address)->is_AddP(), "unexpected address shape"); assert(address->in(AddPNode::Address) == adr->in(AddPNode::Base), "unexpected address shape"); address = address->clone(); address->set_req(AddPNode::Base, base); address->set_req(AddPNode::Address, base); address = kit->gvn().transform(address); } else { assert(address == adr->in(AddPNode::Base), "unexpected address shape"); address = base; } adr = adr->clone(); adr->set_req(AddPNode::Base, base); adr->set_req(AddPNode::Address, address); adr = kit->gvn().transform(adr); access.addr().set_node(adr); } } } } Node* ShenandoahBarrierSetC2::store_at_resolved(C2Access& access, C2AccessValue& val) const { DecoratorSet decorators = access.decorators(); const TypePtr* adr_type = access.addr().type(); Node* adr = access.addr().node(); bool anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0; bool on_heap = (decorators & IN_HEAP) != 0; if (!access.is_oop() || (!on_heap && !anonymous)) { return BarrierSetC2::store_at_resolved(access, val); } if (access.is_parse_access()) { C2ParseAccess& parse_access = static_cast(access); GraphKit* kit = parse_access.kit(); uint adr_idx = kit->C->get_alias_index(adr_type); assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" ); Node* value = val.node(); value = shenandoah_storeval_barrier(kit, value); val.set_node(value); shenandoah_write_barrier_pre(kit, true /* do_load */, /*kit->control(),*/ access.base(), adr, adr_idx, val.node(), static_cast(val.type()), NULL /* pre_val */, access.type()); } else { assert(access.is_opt_access(), "only for optimization passes"); assert(((decorators & C2_TIGHLY_COUPLED_ALLOC) != 0 || !ShenandoahSATBBarrier) && (decorators & C2_ARRAY_COPY) != 0, "unexpected caller of this code"); C2OptAccess& opt_access = static_cast(access); PhaseGVN& gvn = opt_access.gvn(); MergeMemNode* mm = opt_access.mem(); if (ShenandoahStoreValReadBarrier) { RegionNode* region = new RegionNode(3); const Type* v_t = gvn.type(val.node()); Node* phi = new PhiNode(region, v_t->isa_oopptr() ? v_t->is_oopptr()->cast_to_nonconst() : v_t); Node* cmp = gvn.transform(new CmpPNode(val.node(), gvn.zerocon(T_OBJECT))); Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::ne)); IfNode* iff = new IfNode(opt_access.ctl(), bol, PROB_LIKELY_MAG(3), COUNT_UNKNOWN); gvn.transform(iff); if (gvn.is_IterGVN()) { gvn.is_IterGVN()->_worklist.push(iff); } else { gvn.record_for_igvn(iff); } Node* null_true = gvn.transform(new IfFalseNode(iff)); Node* null_false = gvn.transform(new IfTrueNode(iff)); region->init_req(1, null_true); region->init_req(2, null_false); phi->init_req(1, gvn.zerocon(T_OBJECT)); Node* cast = new CastPPNode(val.node(), gvn.type(val.node())->join_speculative(TypePtr::NOTNULL)); cast->set_req(0, null_false); cast = gvn.transform(cast); Node* rb = gvn.transform(new ShenandoahReadBarrierNode(null_false, gvn.C->immutable_memory(), cast, false)); phi->init_req(2, rb); opt_access.set_ctl(gvn.transform(region)); val.set_node(gvn.transform(phi)); } if (ShenandoahStoreValEnqueueBarrier) { const TypePtr* adr_type = ShenandoahBarrierNode::brooks_pointer_type(gvn.type(val.node())); int alias = gvn.C->get_alias_index(adr_type); Node* wb = new ShenandoahWriteBarrierNode(gvn.C, opt_access.ctl(), mm->memory_at(alias), val.node()); Node* wb_transformed = gvn.transform(wb); Node* enqueue = gvn.transform(new ShenandoahEnqueueBarrierNode(wb_transformed)); if (wb_transformed == wb) { Node* proj = gvn.transform(new ShenandoahWBMemProjNode(wb)); mm->set_memory_at(alias, proj); } val.set_node(enqueue); } } return BarrierSetC2::store_at_resolved(access, val); } Node* ShenandoahBarrierSetC2::load_at_resolved(C2Access& access, const Type* val_type) const { DecoratorSet decorators = access.decorators(); Node* adr = access.addr().node(); Node* obj = access.base(); bool mismatched = (decorators & C2_MISMATCHED) != 0; bool unknown = (decorators & ON_UNKNOWN_OOP_REF) != 0; bool on_heap = (decorators & IN_HEAP) != 0; bool on_weak = (decorators & ON_WEAK_OOP_REF) != 0; bool is_unordered = (decorators & MO_UNORDERED) != 0; bool need_cpu_mem_bar = !is_unordered || mismatched || !on_heap; Node* top = Compile::current()->top(); Node* offset = adr->is_AddP() ? adr->in(AddPNode::Offset) : top; Node* load = BarrierSetC2::load_at_resolved(access, val_type); // If we are reading the value of the referent field of a Reference // object (either by using Unsafe directly or through reflection) // then, if SATB is enabled, we need to record the referent in an // SATB log buffer using the pre-barrier mechanism. // Also we need to add memory barrier to prevent commoning reads // from this field across safepoint since GC can change its value. bool need_read_barrier = ShenandoahKeepAliveBarrier && (on_heap && (on_weak || (unknown && offset != top && obj != top))); if (!access.is_oop() || !need_read_barrier) { return load; } assert(access.is_parse_access(), "entry not supported at optimization time"); C2ParseAccess& parse_access = static_cast(access); GraphKit* kit = parse_access.kit(); if (on_weak) { // Use the pre-barrier to record the value in the referent field satb_write_barrier_pre(kit, false /* do_load */, NULL /* obj */, NULL /* adr */, max_juint /* alias_idx */, NULL /* val */, NULL /* val_type */, load /* pre_val */, T_OBJECT); // Add memory barrier to prevent commoning reads from this field // across safepoint since GC can change its value. kit->insert_mem_bar(Op_MemBarCPUOrder); } else if (unknown) { // We do not require a mem bar inside pre_barrier if need_mem_bar // is set: the barriers would be emitted by us. insert_pre_barrier(kit, obj, offset, load, !need_cpu_mem_bar); } return load; } Node* ShenandoahBarrierSetC2::atomic_cmpxchg_val_at_resolved(C2AtomicParseAccess& access, Node* expected_val, Node* new_val, const Type* value_type) const { GraphKit* kit = access.kit(); if (access.is_oop()) { new_val = shenandoah_storeval_barrier(kit, new_val); shenandoah_write_barrier_pre(kit, false /* do_load */, NULL, NULL, max_juint, NULL, NULL, expected_val /* pre_val */, T_OBJECT); MemNode::MemOrd mo = access.mem_node_mo(); Node* mem = access.memory(); Node* adr = access.addr().node(); const TypePtr* adr_type = access.addr().type(); Node* load_store = NULL; #ifdef _LP64 if (adr->bottom_type()->is_ptr_to_narrowoop()) { Node *newval_enc = kit->gvn().transform(new EncodePNode(new_val, new_val->bottom_type()->make_narrowoop())); Node *oldval_enc = kit->gvn().transform(new EncodePNode(expected_val, expected_val->bottom_type()->make_narrowoop())); if (ShenandoahCASBarrier) { load_store = kit->gvn().transform(new ShenandoahCompareAndExchangeNNode(kit->control(), mem, adr, newval_enc, oldval_enc, adr_type, value_type->make_narrowoop(), mo)); } else { load_store = kit->gvn().transform(new CompareAndExchangeNNode(kit->control(), mem, adr, newval_enc, oldval_enc, adr_type, value_type->make_narrowoop(), mo)); } } else #endif { if (ShenandoahCASBarrier) { load_store = kit->gvn().transform(new ShenandoahCompareAndExchangePNode(kit->control(), mem, adr, new_val, expected_val, adr_type, value_type->is_oopptr(), mo)); } else { load_store = kit->gvn().transform(new CompareAndExchangePNode(kit->control(), mem, adr, new_val, expected_val, adr_type, value_type->is_oopptr(), mo)); } } access.set_raw_access(load_store); pin_atomic_op(access); #ifdef _LP64 if (adr->bottom_type()->is_ptr_to_narrowoop()) { return kit->gvn().transform(new DecodeNNode(load_store, load_store->get_ptr_type())); } #endif return load_store; } return BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, value_type); } Node* ShenandoahBarrierSetC2::atomic_cmpxchg_bool_at_resolved(C2AtomicParseAccess& access, Node* expected_val, Node* new_val, const Type* value_type) const { GraphKit* kit = access.kit(); if (access.is_oop()) { new_val = shenandoah_storeval_barrier(kit, new_val); shenandoah_write_barrier_pre(kit, false /* do_load */, NULL, NULL, max_juint, NULL, NULL, expected_val /* pre_val */, T_OBJECT); DecoratorSet decorators = access.decorators(); MemNode::MemOrd mo = access.mem_node_mo(); Node* mem = access.memory(); bool is_weak_cas = (decorators & C2_WEAK_CMPXCHG) != 0; Node* load_store = NULL; Node* adr = access.addr().node(); #ifdef _LP64 if (adr->bottom_type()->is_ptr_to_narrowoop()) { Node *newval_enc = kit->gvn().transform(new EncodePNode(new_val, new_val->bottom_type()->make_narrowoop())); Node *oldval_enc = kit->gvn().transform(new EncodePNode(expected_val, expected_val->bottom_type()->make_narrowoop())); if (ShenandoahCASBarrier) { if (is_weak_cas) { load_store = kit->gvn().transform(new ShenandoahWeakCompareAndSwapNNode(kit->control(), mem, adr, newval_enc, oldval_enc, mo)); } else { load_store = kit->gvn().transform(new ShenandoahCompareAndSwapNNode(kit->control(), mem, adr, newval_enc, oldval_enc, mo)); } } else { if (is_weak_cas) { load_store = kit->gvn().transform(new WeakCompareAndSwapNNode(kit->control(), mem, adr, newval_enc, oldval_enc, mo)); } else { load_store = kit->gvn().transform(new CompareAndSwapNNode(kit->control(), mem, adr, newval_enc, oldval_enc, mo)); } } } else #endif { if (ShenandoahCASBarrier) { if (is_weak_cas) { load_store = kit->gvn().transform(new ShenandoahWeakCompareAndSwapPNode(kit->control(), mem, adr, new_val, expected_val, mo)); } else { load_store = kit->gvn().transform(new ShenandoahCompareAndSwapPNode(kit->control(), mem, adr, new_val, expected_val, mo)); } } else { if (is_weak_cas) { load_store = kit->gvn().transform(new WeakCompareAndSwapPNode(kit->control(), mem, adr, new_val, expected_val, mo)); } else { load_store = kit->gvn().transform(new CompareAndSwapPNode(kit->control(), mem, adr, new_val, expected_val, mo)); } } } access.set_raw_access(load_store); pin_atomic_op(access); return load_store; } return BarrierSetC2::atomic_cmpxchg_bool_at_resolved(access, expected_val, new_val, value_type); } Node* ShenandoahBarrierSetC2::atomic_xchg_at_resolved(C2AtomicParseAccess& access, Node* val, const Type* value_type) const { GraphKit* kit = access.kit(); if (access.is_oop()) { val = shenandoah_storeval_barrier(kit, val); } Node* result = BarrierSetC2::atomic_xchg_at_resolved(access, val, value_type); if (access.is_oop()) { shenandoah_write_barrier_pre(kit, false /* do_load */, NULL, NULL, max_juint, NULL, NULL, result /* pre_val */, T_OBJECT); } return result; } void ShenandoahBarrierSetC2::clone(GraphKit* kit, Node* src, Node* dst, Node* size, bool is_array) const { assert(!src->is_AddP(), "unexpected input"); src = shenandoah_read_barrier(kit, src); BarrierSetC2::clone(kit, src, dst, size, is_array); } Node* ShenandoahBarrierSetC2::resolve(GraphKit* kit, Node* n, DecoratorSet decorators) const { bool is_write = decorators & ACCESS_WRITE; if (is_write) { return shenandoah_write_barrier(kit, n); } else { return shenandoah_read_barrier(kit, n); } } Node* ShenandoahBarrierSetC2::obj_allocate(PhaseMacroExpand* macro, Node* ctrl, Node* mem, Node* toobig_false, Node* size_in_bytes, Node*& i_o, Node*& needgc_ctrl, Node*& fast_oop_ctrl, Node*& fast_oop_rawmem, intx prefetch_lines) const { PhaseIterGVN& igvn = macro->igvn(); // Allocate several words more for the Shenandoah brooks pointer. size_in_bytes = new AddXNode(size_in_bytes, igvn.MakeConX(ShenandoahBrooksPointer::byte_size())); macro->transform_later(size_in_bytes); Node* fast_oop = BarrierSetC2::obj_allocate(macro, ctrl, mem, toobig_false, size_in_bytes, i_o, needgc_ctrl, fast_oop_ctrl, fast_oop_rawmem, prefetch_lines); // Bump up object for Shenandoah brooks pointer. fast_oop = new AddPNode(macro->top(), fast_oop, igvn.MakeConX(ShenandoahBrooksPointer::byte_size())); macro->transform_later(fast_oop); // Initialize Shenandoah brooks pointer to point to the object itself. fast_oop_rawmem = macro->make_store(fast_oop_ctrl, fast_oop_rawmem, fast_oop, ShenandoahBrooksPointer::byte_offset(), fast_oop, T_OBJECT); return fast_oop; } // Support for GC barriers emitted during parsing bool ShenandoahBarrierSetC2::is_gc_barrier_node(Node* node) const { if (node->Opcode() != Op_CallLeaf && node->Opcode() != Op_CallLeafNoFP) { return false; } CallLeafNode *call = node->as_CallLeaf(); if (call->_name == NULL) { return false; } return strcmp(call->_name, "shenandoah_clone_barrier") == 0 || strcmp(call->_name, "shenandoah_cas_obj") == 0 || strcmp(call->_name, "shenandoah_wb_pre") == 0; } Node* ShenandoahBarrierSetC2::step_over_gc_barrier(Node* c) const { return ShenandoahBarrierNode::skip_through_barrier(c); } bool ShenandoahBarrierSetC2::expand_barriers(Compile* C, PhaseIterGVN& igvn) const { return !ShenandoahWriteBarrierNode::expand(C, igvn); } bool ShenandoahBarrierSetC2::optimize_loops(PhaseIdealLoop* phase, LoopOptsMode mode, VectorSet& visited, Node_Stack& nstack, Node_List& worklist) const { if (mode == LoopOptsShenandoahExpand) { assert(UseShenandoahGC, "only for shenandoah"); ShenandoahWriteBarrierNode::pin_and_expand(phase); return true; } else if (mode == LoopOptsShenandoahPostExpand) { assert(UseShenandoahGC, "only for shenandoah"); visited.Clear(); ShenandoahWriteBarrierNode::optimize_after_expansion(visited, nstack, worklist, phase); return true; } GrowableArray memory_graph_fixers; ShenandoahWriteBarrierNode::optimize_before_expansion(phase, memory_graph_fixers, false); return false; } bool ShenandoahBarrierSetC2::array_copy_requires_gc_barriers(bool tightly_coupled_alloc, BasicType type, bool is_clone, ArrayCopyPhase phase) const { bool is_oop = type == T_OBJECT || type == T_ARRAY; if (!is_oop) { return false; } if (tightly_coupled_alloc) { if (phase == Optimization) { return false; } return !is_clone; } if (phase == Optimization) { return !ShenandoahStoreValEnqueueBarrier; } return true; } bool ShenandoahBarrierSetC2::clone_needs_postbarrier(ArrayCopyNode *ac, PhaseIterGVN& igvn) { Node* src = ac->in(ArrayCopyNode::Src); const TypeOopPtr* src_type = igvn.type(src)->is_oopptr(); if (src_type->isa_instptr() != NULL) { ciInstanceKlass* ik = src_type->klass()->as_instance_klass(); if ((src_type->klass_is_exact() || (!ik->is_interface() && !ik->has_subklass())) && !ik->has_injected_fields()) { if (ik->has_object_fields()) { return true; } else { if (!src_type->klass_is_exact()) { igvn.C->dependencies()->assert_leaf_type(ik); } } } else { return true; } } else if (src_type->isa_aryptr()) { BasicType src_elem = src_type->klass()->as_array_klass()->element_type()->basic_type(); if (src_elem == T_OBJECT || src_elem == T_ARRAY) { return true; } } else { return true; } return false; } void ShenandoahBarrierSetC2::clone_barrier_at_expansion(ArrayCopyNode* ac, Node* call, PhaseIterGVN& igvn) const { assert(ac->is_clonebasic(), "no other kind of arraycopy here"); if (!clone_needs_postbarrier(ac, igvn)) { BarrierSetC2::clone_barrier_at_expansion(ac, call, igvn); return; } const TypePtr* raw_adr_type = TypeRawPtr::BOTTOM; Node* c = new ProjNode(call,TypeFunc::Control); c = igvn.transform(c); Node* m = new ProjNode(call, TypeFunc::Memory); m = igvn.transform(m); Node* dest = ac->in(ArrayCopyNode::Dest); assert(dest->is_AddP(), "bad input"); Node* barrier_call = new CallLeafNode(ShenandoahBarrierSetC2::shenandoah_clone_barrier_Type(), CAST_FROM_FN_PTR(address, ShenandoahRuntime::shenandoah_clone_barrier), "shenandoah_clone_barrier", raw_adr_type); barrier_call->init_req(TypeFunc::Control, c); barrier_call->init_req(TypeFunc::I_O , igvn.C->top()); barrier_call->init_req(TypeFunc::Memory , m); barrier_call->init_req(TypeFunc::ReturnAdr, igvn.C->top()); barrier_call->init_req(TypeFunc::FramePtr, igvn.C->top()); barrier_call->init_req(TypeFunc::Parms+0, dest->in(AddPNode::Base)); barrier_call = igvn.transform(barrier_call); c = new ProjNode(barrier_call,TypeFunc::Control); c = igvn.transform(c); m = new ProjNode(barrier_call, TypeFunc::Memory); m = igvn.transform(m); Node* out_c = ac->proj_out(TypeFunc::Control); Node* out_m = ac->proj_out(TypeFunc::Memory); igvn.replace_node(out_c, c); igvn.replace_node(out_m, m); } // Support for macro expanded GC barriers void ShenandoahBarrierSetC2::register_potential_barrier_node(Node* node) const { if (node->Opcode() == Op_ShenandoahWriteBarrier) { state()->add_shenandoah_barrier((ShenandoahWriteBarrierNode*) node); } } void ShenandoahBarrierSetC2::unregister_potential_barrier_node(Node* node) const { if (node->Opcode() == Op_ShenandoahWriteBarrier) { state()->remove_shenandoah_barrier((ShenandoahWriteBarrierNode*) node); } } void ShenandoahBarrierSetC2::eliminate_gc_barrier(PhaseMacroExpand* macro, Node* n) const { if (is_shenandoah_wb_pre_call(n)) { shenandoah_eliminate_wb_pre(n, ¯o->igvn()); } } void ShenandoahBarrierSetC2::shenandoah_eliminate_wb_pre(Node* call, PhaseIterGVN* igvn) const { assert(UseShenandoahGC && is_shenandoah_wb_pre_call(call), ""); Node* c = call->as_Call()->proj_out(TypeFunc::Control); c = c->unique_ctrl_out(); assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?"); c = c->unique_ctrl_out(); assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?"); Node* iff = c->in(1)->is_IfProj() ? c->in(1)->in(0) : c->in(2)->in(0); assert(iff->is_If(), "expect test"); if (!is_shenandoah_marking_if(igvn, iff)) { c = c->unique_ctrl_out(); assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?"); iff = c->in(1)->is_IfProj() ? c->in(1)->in(0) : c->in(2)->in(0); assert(is_shenandoah_marking_if(igvn, iff), "expect marking test"); } Node* cmpx = iff->in(1)->in(1); igvn->replace_node(cmpx, igvn->makecon(TypeInt::CC_EQ)); igvn->rehash_node_delayed(call); call->del_req(call->req()-1); } void ShenandoahBarrierSetC2::enqueue_useful_gc_barrier(PhaseIterGVN* igvn, Node* node) const { if (node->Opcode() == Op_AddP && ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(node)) { igvn->add_users_to_worklist(node); } } void ShenandoahBarrierSetC2::eliminate_useless_gc_barriers(Unique_Node_List &useful, Compile* C) const { for (uint i = 0; i < useful.size(); i++) { Node* n = useful.at(i); if (n->Opcode() == Op_AddP && ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(n)) { for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { C->record_for_igvn(n->fast_out(i)); } } } for (int i = state()->shenandoah_barriers_count()-1; i >= 0; i--) { ShenandoahWriteBarrierNode* n = state()->shenandoah_barrier(i); if (!useful.member(n)) { state()->remove_shenandoah_barrier(n); } } } bool ShenandoahBarrierSetC2::has_special_unique_user(const Node* node) const { assert(node->outcnt() == 1, "match only for unique out"); Node* n = node->unique_out(); return node->Opcode() == Op_ShenandoahWriteBarrier && n->Opcode() == Op_ShenandoahWBMemProj; } void ShenandoahBarrierSetC2::add_users_to_worklist(Unique_Node_List* worklist) const {} void* ShenandoahBarrierSetC2::create_barrier_state(Arena* comp_arena) const { return new(comp_arena) ShenandoahBarrierSetC2State(comp_arena); } ShenandoahBarrierSetC2State* ShenandoahBarrierSetC2::state() const { return reinterpret_cast(Compile::current()->barrier_set_state()); } // If the BarrierSetC2 state has kept macro nodes in its compilation unit state to be // expanded later, then now is the time to do so. bool ShenandoahBarrierSetC2::expand_macro_nodes(PhaseMacroExpand* macro) const { return false; } #ifdef ASSERT void ShenandoahBarrierSetC2::verify_gc_barriers(Compile* compile, CompilePhase phase) const { if (ShenandoahVerifyOptoBarriers && phase == BarrierSetC2::BeforeExpand) { ShenandoahBarrierNode::verify(Compile::current()->root()); } else if (phase == BarrierSetC2::BeforeCodeGen) { // Verify G1 pre-barriers const int marking_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset()); ResourceArea *area = Thread::current()->resource_area(); Unique_Node_List visited(area); Node_List worklist(area); // We're going to walk control flow backwards starting from the Root worklist.push(compile->root()); while (worklist.size() > 0) { Node *x = worklist.pop(); if (x == NULL || x == compile->top()) continue; if (visited.member(x)) { continue; } else { visited.push(x); } if (x->is_Region()) { for (uint i = 1; i < x->req(); i++) { worklist.push(x->in(i)); } } else { worklist.push(x->in(0)); // We are looking for the pattern: // /->ThreadLocal // If->Bool->CmpI->LoadB->AddP->ConL(marking_offset) // \->ConI(0) // We want to verify that the If and the LoadB have the same control // See GraphKit::g1_write_barrier_pre() if (x->is_If()) { IfNode *iff = x->as_If(); if (iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) { CmpNode *cmp = iff->in(1)->in(1)->as_Cmp(); if (cmp->Opcode() == Op_CmpI && cmp->in(2)->is_Con() && cmp->in(2)->bottom_type()->is_int()->get_con() == 0 && cmp->in(1)->is_Load()) { LoadNode *load = cmp->in(1)->as_Load(); if (load->Opcode() == Op_LoadB && load->in(2)->is_AddP() && load->in(2)->in(2)->Opcode() == Op_ThreadLocal && load->in(2)->in(3)->is_Con() && load->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == marking_offset) { Node *if_ctrl = iff->in(0); Node *load_ctrl = load->in(0); if (if_ctrl != load_ctrl) { // Skip possible CProj->NeverBranch in infinite loops if ((if_ctrl->is_Proj() && if_ctrl->Opcode() == Op_CProj) && (if_ctrl->in(0)->is_MultiBranch() && if_ctrl->in(0)->Opcode() == Op_NeverBranch)) { if_ctrl = if_ctrl->in(0)->in(0); } } assert(load_ctrl != NULL && if_ctrl == load_ctrl, "controls must match"); } } } } } } } } #endif Node* ShenandoahBarrierSetC2::ideal_node(PhaseGVN* phase, Node* n, bool can_reshape) const { if (is_shenandoah_wb_pre_call(n)) { uint cnt = ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type()->domain_sig()->cnt(); if (n->req() > cnt) { Node* addp = n->in(cnt); if (has_only_shenandoah_wb_pre_uses(addp)) { n->del_req(cnt); if (can_reshape) { phase->is_IterGVN()->_worklist.push(addp); } return n; } } } if (n->Opcode() == Op_CmpP) { Node* in1 = n->in(1); Node* in2 = n->in(2); if (in1->bottom_type() == TypePtr::NULL_PTR) { in2 = step_over_gc_barrier(in2); } if (in2->bottom_type() == TypePtr::NULL_PTR) { in1 = step_over_gc_barrier(in1); } PhaseIterGVN* igvn = phase->is_IterGVN(); if (in1 != n->in(1)) { if (igvn != NULL) { n->set_req_X(1, in1, igvn); } else { n->set_req(1, in1); } assert(in2 == n->in(2), "only one change"); return n; } if (in2 != n->in(2)) { if (igvn != NULL) { n->set_req_X(2, in2, igvn); } else { n->set_req(2, in2); } return n; } } else if (can_reshape && n->Opcode() == Op_If && ShenandoahWriteBarrierNode::is_heap_stable_test(n) && n->in(0) != NULL) { Node* dom = n->in(0); Node* prev_dom = n; int op = n->Opcode(); int dist = 16; // Search up the dominator tree for another heap stable test while (dom->Opcode() != op || // Not same opcode? !ShenandoahWriteBarrierNode::is_heap_stable_test(dom) || // Not same input 1? prev_dom->in(0) != dom) { // One path of test does not dominate? if (dist < 0) return NULL; dist--; prev_dom = dom; dom = IfNode::up_one_dom(dom); if (!dom) return NULL; } // Check that we did not follow a loop back to ourselves if (n == dom) { return NULL; } return n->as_If()->dominated_by(prev_dom, phase->is_IterGVN()); } return NULL; } Node* ShenandoahBarrierSetC2::identity_node(PhaseGVN* phase, Node* n) const { if (n->is_Load()) { Node *mem = n->in(MemNode::Memory); Node *value = n->as_Load()->can_see_stored_value(mem, phase); if (value) { PhaseIterGVN *igvn = phase->is_IterGVN(); if (igvn != NULL && value->is_Phi() && value->req() > 2 && value->in(1) != NULL && value->in(1)->is_ShenandoahBarrier()) { if (igvn->_worklist.member(value) || igvn->_worklist.member(value->in(0)) || (value->in(0)->in(1) != NULL && value->in(0)->in(1)->is_IfProj() && (igvn->_worklist.member(value->in(0)->in(1)) || (value->in(0)->in(1)->in(0) != NULL && igvn->_worklist.member(value->in(0)->in(1)->in(0)))))) { igvn->_worklist.push(n); return n; } } // (This works even when value is a Con, but LoadNode::Value // usually runs first, producing the singleton type of the Con.) Node *value_no_barrier = step_over_gc_barrier(value->Opcode() == Op_EncodeP ? value->in(1) : value); if (value->Opcode() == Op_EncodeP) { if (value_no_barrier != value->in(1)) { Node *encode = value->clone(); encode->set_req(1, value_no_barrier); encode = phase->transform(encode); return encode; } } else { return value_no_barrier; } } } return n; } bool ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(Node* n) { for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { Node* u = n->fast_out(i); if (!is_shenandoah_wb_pre_call(u)) { return false; } } return n->outcnt() > 0; } bool ShenandoahBarrierSetC2::flatten_gc_alias_type(const TypePtr*& adr_type) const { int offset = adr_type->offset(); if (offset == ShenandoahBrooksPointer::byte_offset()) { if (adr_type->isa_aryptr()) { adr_type = TypeAryPtr::make(adr_type->ptr(), adr_type->isa_aryptr()->ary(), adr_type->isa_aryptr()->klass(), false, Type::Offset(offset)); } else if (adr_type->isa_instptr()) { adr_type = TypeInstPtr::make(adr_type->ptr(), ciEnv::current()->Object_klass(), false, NULL, Type::Offset(offset)); } return true; } else { return false; } } bool ShenandoahBarrierSetC2::final_graph_reshaping(Compile* compile, Node* n, uint opcode) const { switch (opcode) { case Op_CallLeaf: case Op_CallLeafNoFP: { assert (n->is_Call(), ""); CallNode *call = n->as_Call(); if (ShenandoahBarrierSetC2::is_shenandoah_wb_pre_call(call)) { uint cnt = ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type()->domain_sig()->cnt(); if (call->req() > cnt) { assert(call->req() == cnt + 1, "only one extra input"); Node *addp = call->in(cnt); assert(!ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(addp), "useless address computation?"); call->del_req(cnt); } } return false; } case Op_ShenandoahCompareAndSwapP: case Op_ShenandoahCompareAndSwapN: case Op_ShenandoahWeakCompareAndSwapN: case Op_ShenandoahWeakCompareAndSwapP: case Op_ShenandoahCompareAndExchangeP: case Op_ShenandoahCompareAndExchangeN: #ifdef ASSERT if( VerifyOptoOopOffsets ) { MemNode* mem = n->as_Mem(); // Check to see if address types have grounded out somehow. const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr(); ciInstanceKlass *k = tp->klass()->as_instance_klass(); bool oop_offset_is_sane = k->contains_field_offset(tp->offset()); assert( !tp || oop_offset_is_sane, "" ); } #endif return true; case Op_ShenandoahReadBarrier: return true; case Op_ShenandoahWriteBarrier: assert(false, "should have been expanded already"); return true; default: return false; } } #ifdef ASSERT bool ShenandoahBarrierSetC2::verify_gc_alias_type(const TypePtr* adr_type, int offset) const { if (offset == ShenandoahBrooksPointer::byte_offset() && (adr_type->base() == Type::AryPtr || adr_type->base() == Type::OopPtr)) { return true; } else { return false; } } #endif bool ShenandoahBarrierSetC2::escape_add_to_con_graph(ConnectionGraph* conn_graph, PhaseGVN* gvn, Unique_Node_List* delayed_worklist, Node* n, uint opcode) const { switch (opcode) { case Op_ShenandoahCompareAndExchangeP: case Op_ShenandoahCompareAndExchangeN: conn_graph->add_objload_to_connection_graph(n, delayed_worklist); // fallthrough case Op_ShenandoahWeakCompareAndSwapP: case Op_ShenandoahWeakCompareAndSwapN: case Op_ShenandoahCompareAndSwapP: case Op_ShenandoahCompareAndSwapN: conn_graph->add_to_congraph_unsafe_access(n, opcode, delayed_worklist); return true; case Op_StoreP: { Node* adr = n->in(MemNode::Address); const Type* adr_type = gvn->type(adr); // Pointer stores in G1 barriers looks like unsafe access. // Ignore such stores to be able scalar replace non-escaping // allocations. if (adr_type->isa_rawptr() && adr->is_AddP()) { Node* base = conn_graph->get_addp_base(adr); if (base->Opcode() == Op_LoadP && base->in(MemNode::Address)->is_AddP()) { adr = base->in(MemNode::Address); Node* tls = conn_graph->get_addp_base(adr); if (tls->Opcode() == Op_ThreadLocal) { int offs = (int) gvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); const int buf_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()); if (offs == buf_offset) { return true; // Pre barrier previous oop value store. } } } } return false; } case Op_ShenandoahReadBarrier: case Op_ShenandoahWriteBarrier: // Barriers 'pass through' its arguments. I.e. what goes in, comes out. // It doesn't escape. conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(ShenandoahBarrierNode::ValueIn), delayed_worklist); break; case Op_ShenandoahEnqueueBarrier: conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), delayed_worklist); break; default: // Nothing break; } return false; } bool ShenandoahBarrierSetC2::escape_add_final_edges(ConnectionGraph* conn_graph, PhaseGVN* gvn, Node* n, uint opcode) const { switch (opcode) { case Op_ShenandoahCompareAndExchangeP: case Op_ShenandoahCompareAndExchangeN: { Node *adr = n->in(MemNode::Address); conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL); // fallthrough } case Op_ShenandoahCompareAndSwapP: case Op_ShenandoahCompareAndSwapN: case Op_ShenandoahWeakCompareAndSwapP: case Op_ShenandoahWeakCompareAndSwapN: return conn_graph->add_final_edges_unsafe_access(n, opcode); case Op_ShenandoahReadBarrier: case Op_ShenandoahWriteBarrier: // Barriers 'pass through' its arguments. I.e. what goes in, comes out. // It doesn't escape. conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(ShenandoahBarrierNode::ValueIn), NULL); return true; case Op_ShenandoahEnqueueBarrier: conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), NULL); return true; default: // Nothing break; } return false; } bool ShenandoahBarrierSetC2::escape_has_out_with_unsafe_object(Node* n) const { return n->has_out_with(Op_ShenandoahCompareAndExchangeP) || n->has_out_with(Op_ShenandoahCompareAndExchangeN) || n->has_out_with(Op_ShenandoahCompareAndSwapP, Op_ShenandoahCompareAndSwapN, Op_ShenandoahWeakCompareAndSwapP, Op_ShenandoahWeakCompareAndSwapN); } bool ShenandoahBarrierSetC2::escape_is_barrier_node(Node* n) const { return n->is_ShenandoahBarrier(); } bool ShenandoahBarrierSetC2::matcher_find_shared_visit(Matcher* matcher, Matcher::MStack& mstack, Node* n, uint opcode, bool& mem_op, int& mem_addr_idx) const { switch (opcode) { case Op_ShenandoahReadBarrier: if (n->in(ShenandoahBarrierNode::ValueIn)->is_DecodeNarrowPtr()) { matcher->set_shared(n->in(ShenandoahBarrierNode::ValueIn)->in(1)); } matcher->set_shared(n); return true; default: break; } return false; } bool ShenandoahBarrierSetC2::matcher_find_shared_post_visit(Matcher* matcher, Node* n, uint opcode) const { switch (opcode) { case Op_ShenandoahCompareAndExchangeP: case Op_ShenandoahCompareAndExchangeN: case Op_ShenandoahWeakCompareAndSwapP: case Op_ShenandoahWeakCompareAndSwapN: case Op_ShenandoahCompareAndSwapP: case Op_ShenandoahCompareAndSwapN: { // Convert trinary to binary-tree Node* newval = n->in(MemNode::ValueIn); Node* oldval = n->in(LoadStoreConditionalNode::ExpectedIn); Node* pair = new BinaryNode(oldval, newval); n->set_req(MemNode::ValueIn,pair); n->del_req(LoadStoreConditionalNode::ExpectedIn); return true; } default: break; } return false; } bool ShenandoahBarrierSetC2::matcher_is_store_load_barrier(Node* x, uint xop) const { return xop == Op_ShenandoahCompareAndExchangeP || xop == Op_ShenandoahCompareAndExchangeN || xop == Op_ShenandoahWeakCompareAndSwapP || xop == Op_ShenandoahWeakCompareAndSwapN || xop == Op_ShenandoahCompareAndSwapN || xop == Op_ShenandoahCompareAndSwapP; } void ShenandoahBarrierSetC2::igvn_add_users_to_worklist(PhaseIterGVN* igvn, Node* use) const { if (use->is_ShenandoahBarrier()) { for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) { Node* u = use->fast_out(i2); Node* cmp = use->find_out_with(Op_CmpP); if (u->Opcode() == Op_CmpP) { igvn->_worklist.push(cmp); } } } } void ShenandoahBarrierSetC2::ccp_analyze(PhaseCCP* ccp, Unique_Node_List& worklist, Node* use) const { if (use->is_ShenandoahBarrier()) { for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) { Node* p = use->fast_out(i2); if (p->Opcode() == Op_AddP) { for (DUIterator_Fast i3max, i3 = p->fast_outs(i3max); i3 < i3max; i3++) { Node* q = p->fast_out(i3); if (q->is_Load()) { if(q->bottom_type() != ccp->type(q)) { worklist.push(q); } } } } } } } Node* ShenandoahBarrierSetC2::split_if_pre(PhaseIdealLoop* phase, Node* n) const { if (n->Opcode() == Op_ShenandoahReadBarrier) { ((ShenandoahReadBarrierNode*)n)->try_move(phase); } else if (n->Opcode() == Op_ShenandoahWriteBarrier) { return ((ShenandoahWriteBarrierNode*)n)->try_split_thru_phi(phase); } return NULL; } bool ShenandoahBarrierSetC2::build_loop_late_post(PhaseIdealLoop* phase, Node* n) const { return ShenandoahBarrierNode::build_loop_late_post(phase, n); } bool ShenandoahBarrierSetC2::sink_node(PhaseIdealLoop* phase, Node* n, Node* x, Node* x_ctrl, Node* n_ctrl) const { if (n->is_ShenandoahBarrier()) { return x->as_ShenandoahBarrier()->sink_node(phase, x_ctrl, n_ctrl); } if (n->is_MergeMem()) { // PhaseIdealLoop::split_if_with_blocks_post() would: // _igvn._worklist.yank(x); // which sometimes causes chains of MergeMem which some of // shenandoah specific code doesn't support phase->register_new_node(x, x_ctrl); return true; } return false; }