--- /dev/null 2020-02-06 11:34:07.664987501 +0100 +++ new/src/hotspot/share/gc/shenandoah/c2/shenandoahBarrierSetC2.cpp 2020-02-06 19:19:12.276544300 +0100 @@ -0,0 +1,1046 @@ +/* + * 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/shenandoahForwarding.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" +#include "opto/runtime.hpp" + +ShenandoahBarrierSetC2* ShenandoahBarrierSetC2::bsc2() { + return reinterpret_cast(BarrierSet::barrier_set()->barrier_set_c2()); +} + +ShenandoahBarrierSetC2State::ShenandoahBarrierSetC2State(Arena* comp_arena) + : _enqueue_barriers(new (comp_arena) GrowableArray(comp_arena, 8, 0, NULL)), + _load_reference_barriers(new (comp_arena) GrowableArray(comp_arena, 8, 0, NULL)) { +} + +int ShenandoahBarrierSetC2State::enqueue_barriers_count() const { + return _enqueue_barriers->length(); +} + +ShenandoahEnqueueBarrierNode* ShenandoahBarrierSetC2State::enqueue_barrier(int idx) const { + return _enqueue_barriers->at(idx); +} + +void ShenandoahBarrierSetC2State::add_enqueue_barrier(ShenandoahEnqueueBarrierNode * n) { + assert(!_enqueue_barriers->contains(n), "duplicate entry in barrier list"); + _enqueue_barriers->append(n); +} + +void ShenandoahBarrierSetC2State::remove_enqueue_barrier(ShenandoahEnqueueBarrierNode * n) { + if (_enqueue_barriers->contains(n)) { + _enqueue_barriers->remove(n); + } +} + +int ShenandoahBarrierSetC2State::load_reference_barriers_count() const { + return _load_reference_barriers->length(); +} + +ShenandoahLoadReferenceBarrierNode* ShenandoahBarrierSetC2State::load_reference_barrier(int idx) const { + return _load_reference_barriers->at(idx); +} + +void ShenandoahBarrierSetC2State::add_load_reference_barrier(ShenandoahLoadReferenceBarrierNode * n) { + assert(!_load_reference_barriers->contains(n), "duplicate entry in barrier list"); + _load_reference_barriers->append(n); +} + +void ShenandoahBarrierSetC2State::remove_load_reference_barrier(ShenandoahLoadReferenceBarrierNode * n) { + if (_load_reference_barriers->contains(n)) { + _load_reference_barriers->remove(n); + } +} + +Node* ShenandoahBarrierSetC2::shenandoah_storeval_barrier(GraphKit* kit, Node* obj) const { + if (ShenandoahStoreValEnqueueBarrier) { + obj = shenandoah_enqueue_barrier(kit, obj); + } + return obj; +} + +#define __ kit-> + +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(ShenandoahBarrierC2Support::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 Shenandoah 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_lrb_call(Node* call) { + if (!call->is_CallLeaf()) { + return false; + } + + address entry_point = call->as_CallLeaf()->entry_point(); + return (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier)) || + (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_narrow)); +} + +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] = TypeOopPtr::NOTNULL; // src oop + 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_load_reference_barrier_Type() { + const Type **fields = TypeTuple::fields(2); + fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL; // original field value + fields[TypeFunc::Parms+1] = TypeRawPtr::BOTTOM; // original load address + + const TypeTuple *domain = TypeTuple::make(TypeFunc::Parms+2, 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); +} + +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); + } + + GraphKit* kit = 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()); + 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 (access.is_oop()) { + if (ShenandoahLoadRefBarrier) { + load = new ShenandoahLoadReferenceBarrierNode(NULL, load); + load = access.kit()->gvn().transform(load); + } + } + + // 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; + } + + GraphKit* kit = 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; +} + +static void pin_atomic_op(C2AtomicAccess& access) { + if (!access.needs_pinning()) { + return; + } + // SCMemProjNodes represent the memory state of a LoadStore. Their + // main role is to prevent LoadStore nodes from being optimized away + // when their results aren't used. + GraphKit* kit = access.kit(); + Node* load_store = access.raw_access(); + assert(load_store != NULL, "must pin atomic op"); + Node* proj = kit->gvn().transform(new SCMemProjNode(load_store)); + kit->set_memory(proj, access.alias_idx()); +} + +Node* ShenandoahBarrierSetC2::atomic_cmpxchg_val_at_resolved(C2AtomicAccess& 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()) { + load_store = kit->gvn().transform(new DecodeNNode(load_store, load_store->get_ptr_type())); + } +#endif + load_store = kit->gvn().transform(new ShenandoahLoadReferenceBarrierNode(NULL, load_store)); + return load_store; + } + return BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, value_type); +} + +Node* ShenandoahBarrierSetC2::atomic_cmpxchg_bool_at_resolved(C2AtomicAccess& 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(C2AtomicAccess& 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()) { + result = kit->gvn().transform(new ShenandoahLoadReferenceBarrierNode(NULL, result)); + shenandoah_write_barrier_pre(kit, false /* do_load */, + NULL, NULL, max_juint, NULL, NULL, + result /* pre_val */, T_OBJECT); + } + return result; +} + +// Support for GC barriers emitted during parsing +bool ShenandoahBarrierSetC2::is_gc_barrier_node(Node* node) const { + if (node->Opcode() == Op_ShenandoahLoadReferenceBarrier) return true; + 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 { + if (c->Opcode() == Op_ShenandoahLoadReferenceBarrier) { + return c->in(ShenandoahLoadReferenceBarrierNode::ValueIn); + } + if (c->Opcode() == Op_ShenandoahEnqueueBarrier) { + c = c->in(1); + } + return c; +} + +bool ShenandoahBarrierSetC2::expand_barriers(Compile* C, PhaseIterGVN& igvn) const { + return !ShenandoahBarrierC2Support::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"); + ShenandoahBarrierC2Support::pin_and_expand(phase); + return true; + } else if (mode == LoopOptsShenandoahPostExpand) { + assert(UseShenandoahGC, "only for shenandoah"); + visited.Clear(); + ShenandoahBarrierC2Support::optimize_after_expansion(visited, nstack, worklist, phase); + return true; + } + return false; +} + +bool ShenandoahBarrierSetC2::array_copy_requires_gc_barriers(BasicType type) const { + return false; +} + +bool ShenandoahBarrierSetC2::clone_needs_barrier(Node* src, PhaseGVN& gvn) { + const TypeOopPtr* src_type = gvn.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()) { + Compile::current()->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_at_expansion(PhaseMacroExpand* phase, ArrayCopyNode* ac) const { + Node* ctrl = ac->in(TypeFunc::Control); + Node* mem = ac->in(TypeFunc::Memory); + Node* src = ac->in(ArrayCopyNode::Src); + Node* src_offset = ac->in(ArrayCopyNode::SrcPos); + Node* dest = ac->in(ArrayCopyNode::Dest); + Node* dest_offset = ac->in(ArrayCopyNode::DestPos); + Node* length = ac->in(ArrayCopyNode::Length); + assert (src_offset == NULL && dest_offset == NULL, "for clone offsets should be null"); + assert (src->is_AddP(), "for clone the src should be the interior ptr"); + assert (dest->is_AddP(), "for clone the dst should be the interior ptr"); + + if (ShenandoahCloneBarrier && clone_needs_barrier(src, phase->igvn())) { + // Check if heap is has forwarded objects. If it does, we need to call into the special + // routine that would fix up source references before we can continue. + + enum { _heap_stable = 1, _heap_unstable, PATH_LIMIT }; + Node* region = new RegionNode(PATH_LIMIT); + Node* mem_phi = new PhiNode(region, Type::MEMORY, TypeRawPtr::BOTTOM); + + Node* thread = phase->transform_later(new ThreadLocalNode()); + Node* offset = phase->igvn().MakeConX(in_bytes(ShenandoahThreadLocalData::gc_state_offset())); + Node* gc_state_addr = phase->transform_later(new AddPNode(phase->C->top(), thread, offset)); + + uint gc_state_idx = Compile::AliasIdxRaw; + const TypePtr* gc_state_adr_type = NULL; // debug-mode-only argument + debug_only(gc_state_adr_type = phase->C->get_adr_type(gc_state_idx)); + + Node* gc_state = phase->transform_later(new LoadBNode(ctrl, mem, gc_state_addr, gc_state_adr_type, TypeInt::BYTE, MemNode::unordered)); + Node* stable_and = phase->transform_later(new AndINode(gc_state, phase->igvn().intcon(ShenandoahHeap::HAS_FORWARDED))); + Node* stable_cmp = phase->transform_later(new CmpINode(stable_and, phase->igvn().zerocon(T_INT))); + Node* stable_test = phase->transform_later(new BoolNode(stable_cmp, BoolTest::ne)); + + IfNode* stable_iff = phase->transform_later(new IfNode(ctrl, stable_test, PROB_UNLIKELY(0.999), COUNT_UNKNOWN))->as_If(); + Node* stable_ctrl = phase->transform_later(new IfFalseNode(stable_iff)); + Node* unstable_ctrl = phase->transform_later(new IfTrueNode(stable_iff)); + + // Heap is stable, no need to do anything additional + region->init_req(_heap_stable, stable_ctrl); + mem_phi->init_req(_heap_stable, mem); + + // Heap is unstable, call into clone barrier stub + Node* call = phase->make_leaf_call(unstable_ctrl, mem, + ShenandoahBarrierSetC2::shenandoah_clone_barrier_Type(), + CAST_FROM_FN_PTR(address, ShenandoahRuntime::shenandoah_clone_barrier), + "shenandoah_clone", + TypeRawPtr::BOTTOM, + src->in(AddPNode::Base)); + call = phase->transform_later(call); + + ctrl = phase->transform_later(new ProjNode(call, TypeFunc::Control)); + mem = phase->transform_later(new ProjNode(call, TypeFunc::Memory)); + region->init_req(_heap_unstable, ctrl); + mem_phi->init_req(_heap_unstable, mem); + + // Wire up the actual arraycopy stub now + ctrl = phase->transform_later(region); + mem = phase->transform_later(mem_phi); + + const char* name = "arraycopy"; + call = phase->make_leaf_call(ctrl, mem, + OptoRuntime::fast_arraycopy_Type(), + phase->basictype2arraycopy(T_LONG, NULL, NULL, true, name, true), + name, TypeRawPtr::BOTTOM, + src, dest, length + LP64_ONLY(COMMA phase->top())); + call = phase->transform_later(call); + + // Hook up the whole thing into the graph + phase->igvn().replace_node(ac, call); + } else { + BarrierSetC2::clone_at_expansion(phase, ac); + } +} + +// Support for macro expanded GC barriers +void ShenandoahBarrierSetC2::register_potential_barrier_node(Node* node) const { + if (node->Opcode() == Op_ShenandoahEnqueueBarrier) { + state()->add_enqueue_barrier((ShenandoahEnqueueBarrierNode*) node); + } + if (node->Opcode() == Op_ShenandoahLoadReferenceBarrier) { + state()->add_load_reference_barrier((ShenandoahLoadReferenceBarrierNode*) node); + } +} + +void ShenandoahBarrierSetC2::unregister_potential_barrier_node(Node* node) const { + if (node->Opcode() == Op_ShenandoahEnqueueBarrier) { + state()->remove_enqueue_barrier((ShenandoahEnqueueBarrierNode*) node); + } + if (node->Opcode() == Op_ShenandoahLoadReferenceBarrier) { + state()->remove_load_reference_barrier((ShenandoahLoadReferenceBarrierNode*) 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(Unique_Node_List &worklist, Node* node) const { + if (node->Opcode() == Op_AddP && ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(node)) { + worklist.push(node); + } +} + +void ShenandoahBarrierSetC2::eliminate_useless_gc_barriers(Unique_Node_List &useful) 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++) { + Compile::current()->record_for_igvn(n->fast_out(i)); + } + } + } + for (int i = state()->enqueue_barriers_count() - 1; i >= 0; i--) { + ShenandoahEnqueueBarrierNode* n = state()->enqueue_barrier(i); + if (!useful.member(n)) { + state()->remove_enqueue_barrier(n); + } + } + for (int i = state()->load_reference_barriers_count() - 1; i >= 0; i--) { + ShenandoahLoadReferenceBarrierNode* n = state()->load_reference_barrier(i); + if (!useful.member(n)) { + state()->remove_load_reference_barrier(n); + } + } +} + +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(bool post_parse) const { + if (ShenandoahVerifyOptoBarriers && !post_parse) { + ShenandoahBarrierC2Support::verify(Compile::current()->root()); + } +} +#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()->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 && + ShenandoahBarrierC2Support::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? + !ShenandoahBarrierC2Support::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; +} + +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; +} + +Node* ShenandoahBarrierSetC2::arraycopy_load_reference_barrier(PhaseGVN *phase, Node* v) { + if (ShenandoahLoadRefBarrier) { + return phase->transform(new ShenandoahLoadReferenceBarrierNode(NULL, v)); + } + if (ShenandoahStoreValEnqueueBarrier) { + return phase->transform(new ShenandoahEnqueueBarrierNode(v)); + } + return v; +} +