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* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
- #include "classfile/javaClasses.hpp"
#include "gc/shared/barrierSet.hpp"
#include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
- #include "gc/shenandoah/c2/shenandoahSupport.hpp"
#include "gc/shenandoah/heuristics/shenandoahHeuristics.hpp"
- #include "gc/shenandoah/shenandoahBarrierSet.hpp"
- #include "gc/shenandoah/shenandoahCardTable.hpp"
#include "gc/shenandoah/shenandoahForwarding.hpp"
#include "gc/shenandoah/shenandoahHeap.hpp"
#include "gc/shenandoah/shenandoahRuntime.hpp"
#include "gc/shenandoah/shenandoahThreadLocalData.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<ShenandoahBarrierSetC2*>(BarrierSet::barrier_set()->barrier_set_c2());
}
! ShenandoahBarrierSetC2State::ShenandoahBarrierSetC2State(Arena* comp_arena)
! : _load_reference_barriers(new (comp_arena) GrowableArray<ShenandoahLoadReferenceBarrierNode*>(comp_arena, 8, 0, nullptr)) {
! }
!
- 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);
- }
}
#define __ kit->
! bool ShenandoahBarrierSetC2::satb_can_remove_pre_barrier(GraphKit* kit, PhaseValues* 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);
if (offset == Type::OffsetBot) {
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "gc/shared/barrierSet.hpp"
#include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
#include "gc/shenandoah/heuristics/shenandoahHeuristics.hpp"
#include "gc/shenandoah/shenandoahForwarding.hpp"
#include "gc/shenandoah/shenandoahHeap.hpp"
#include "gc/shenandoah/shenandoahRuntime.hpp"
#include "gc/shenandoah/shenandoahThreadLocalData.hpp"
#include "opto/arraycopynode.hpp"
#include "opto/escape.hpp"
#include "opto/graphKit.hpp"
#include "opto/idealKit.hpp"
#include "opto/macro.hpp"
#include "opto/narrowptrnode.hpp"
+ #include "opto/output.hpp"
#include "opto/rootnode.hpp"
#include "opto/runtime.hpp"
ShenandoahBarrierSetC2* ShenandoahBarrierSetC2::bsc2() {
return reinterpret_cast<ShenandoahBarrierSetC2*>(BarrierSet::barrier_set()->barrier_set_c2());
}
! ShenandoahBarrierSetC2State::ShenandoahBarrierSetC2State(Arena* comp_arena) :
! BarrierSetC2State(comp_arena),
! _stubs(new (comp_arena) GrowableArray<ShenandoahBarrierStubC2*>(comp_arena, 8, 0, nullptr)),
! _stubs_start_offset(0) {
}
#define __ kit->
! static bool satb_can_remove_pre_barrier(GraphKit* kit, PhaseValues* phase, Node* adr,
! BasicType bt, uint adr_idx) {
intptr_t offset = 0;
Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset);
AllocateNode* alloc = AllocateNode::Ideal_allocation(base);
if (offset == Type::OffsetBot) {
}
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(adr != nullptr, "where are loading from?");
- assert(pre_val == nullptr, "loaded already?");
- assert(val_type != nullptr, "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 != nullptr, "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 != nullptr)
- __ 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_barrier_pre_Type();
- __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_barrier_pre), "shenandoah_wb_pre", pre_val);
- } __ end_if(); // (!index)
- } __ end_if(); // (pre_val != nullptr)
- } __ end_if(); // (!marking)
-
- // Final sync IdealKit and GraphKit.
- kit->final_sync(ideal);
-
- if (ShenandoahSATBBarrier && adr != nullptr) {
- 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_barrier_pre);
}
bool ShenandoahBarrierSetC2::is_shenandoah_clone_call(Node* call) {
return call->is_CallLeaf() &&
call->as_CallLeaf()->entry_point() == CAST_FROM_FN_PTR(address, ShenandoahRuntime::clone_barrier);
}
- 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_strong)) ||
- (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow)) ||
- (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak)) ||
- (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak_narrow)) ||
- (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom)) ||
- (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom_narrow));
- }
-
- bool ShenandoahBarrierSetC2::is_shenandoah_marking_if(PhaseValues* 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);
- }
- }
-
- // 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 Shenandoah
- // 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 != nullptr && 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 != nullptr) {
- if (btype->isa_aryptr()) {
- // Array type so nothing to do
- return;
- }
-
- const TypeInstPtr* itype = btype->isa_instptr();
- if (itype != nullptr) {
- // Can the klass of base_oop be statically determined to be
- // _not_ a sub-class of Reference and _not_ Object?
- ciKlass* klass = itype->instance_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 == nullptr
- __ 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 */,
- nullptr /* obj */, nullptr /* adr */, max_juint /* alias_idx */, nullptr /* val */, nullptr /* 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);
- }
-
- void ShenandoahBarrierSetC2::post_barrier(GraphKit* kit,
- Node* ctl,
- Node* oop_store,
- Node* obj,
- Node* adr,
- uint adr_idx,
- Node* val,
- BasicType bt,
- bool use_precise) const {
- assert(ShenandoahCardBarrier, "Should have been checked by caller");
-
- // No store check needed if we're storing a null.
- if (val != nullptr && val->is_Con()) {
- // must be either an oop or null
- const Type* t = val->bottom_type();
- if (t == TypePtr::NULL_PTR || t == Type::TOP)
- return;
- }
-
- if (ReduceInitialCardMarks && obj == kit->just_allocated_object(kit->control())) {
- // We use card marks to track old to young references in Generational Shenandoah;
- // see flag ShenandoahCardBarrier above.
- // Objects are always allocated in the young generation and initialized
- // before they are promoted. There's always a safepoint (e.g. at final mark)
- // before an object is promoted from young to old. Promotion entails dirtying of
- // the cards backing promoted objects, so they will be guaranteed to be scanned
- // at the next remembered set scan of the old generation.
- // Thus, we can safely skip card-marking of initializing stores on a
- // freshly-allocated object. If any of the assumptions above change in
- // the future, this code will need to be re-examined; see check in
- // ShenandoahCardBarrier::on_slowpath_allocation_exit().
- return;
- }
-
- if (!use_precise) {
- // All card marks for a (non-array) instance are in one place:
- adr = obj;
- }
- // (Else it's an array (or unknown), and we want more precise card marks.)
- assert(adr != nullptr, "");
-
- IdealKit ideal(kit, true);
-
- Node* tls = __ thread(); // ThreadLocalStorage
-
- // Convert the pointer to an int prior to doing math on it
- Node* cast = __ CastPX(__ ctrl(), adr);
-
- Node* curr_ct_holder_offset = __ ConX(in_bytes(ShenandoahThreadLocalData::card_table_offset()));
- Node* curr_ct_holder_addr = __ AddP(__ top(), tls, curr_ct_holder_offset);
- Node* curr_ct_base_addr = __ load( __ ctrl(), curr_ct_holder_addr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
-
- // Divide by card size
- Node* card_offset = __ URShiftX( cast, __ ConI(CardTable::card_shift()) );
-
- // Combine card table base and card offset
- Node* card_adr = __ AddP(__ top(), curr_ct_base_addr, card_offset);
-
- // Get the alias_index for raw card-mark memory
- int adr_type = Compile::AliasIdxRaw;
- Node* zero = __ ConI(0); // Dirty card value
-
- if (UseCondCardMark) {
- // The classic GC reference write barrier is typically implemented
- // as a store into the global card mark table. Unfortunately
- // unconditional stores can result in false sharing and excessive
- // coherence traffic as well as false transactional aborts.
- // UseCondCardMark enables MP "polite" conditional card mark
- // stores. In theory we could relax the load from ctrl() to
- // no_ctrl, but that doesn't buy much latitude.
- Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, T_BYTE, adr_type);
- __ if_then(card_val, BoolTest::ne, zero);
- }
-
- // Smash zero into card
- __ store(__ ctrl(), card_adr, zero, T_BYTE, adr_type, MemNode::unordered);
-
- if (UseCondCardMark) {
- __ end_if();
- }
-
- // Final sync IdealKit and GraphKit.
- kit->final_sync(ideal);
- }
-
- #undef __
-
- const TypeFunc* ShenandoahBarrierSetC2::write_barrier_pre_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::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);
}
return false;
}
! static bool shenandoah_can_remove_post_barrier(GraphKit* kit, PhaseValues* phase, Node* store_ctrl, Node* adr) {
! intptr_t offset = 0;
! Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset);
! AllocateNode* alloc = AllocateNode::Ideal_allocation(base);
! if (offset == Type::OffsetBot) {
! return false; // Cannot unalias unless there are precise offsets.
! }
! if (alloc == nullptr) {
! return false; // No allocation found.
}
! Node* mem = store_ctrl; // Start search from Store node.
! 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 we are looking at the same allocation
+ if (alloc == st_alloc) {
+ return true;
}
}
! return false;
}
bool ShenandoahBarrierSetC2::is_shenandoah_clone_call(Node* call) {
return call->is_CallLeaf() &&
call->as_CallLeaf()->entry_point() == CAST_FROM_FN_PTR(address, ShenandoahRuntime::clone_barrier);
}
const TypeFunc* ShenandoahBarrierSetC2::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);
const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+0, fields);
return TypeFunc::make(domain, range);
}
! const TypeFunc* ShenandoahBarrierSetC2::load_reference_barrier_Type() {
! const Type **fields = TypeTuple::fields(2);
! fields[TypeFunc::Parms+0] = TypeOopPtr::BOTTOM; // 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] = TypeOopPtr::BOTTOM;
! 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 no_keepalive = (decorators & AS_NO_KEEPALIVE) != 0;
!
! if (!access.is_oop()) {
! return BarrierSetC2::store_at_resolved(access, val);
}
-
if (no_keepalive) {
// No keep-alive means no need for the pre-barrier.
! return BarrierSetC2::store_at_resolved(access, val);
}
! if (access.is_parse_access()) {
! C2ParseAccess& parse_access = static_cast<C2ParseAccess&>(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" );
! shenandoah_write_barrier_pre(kit, true /* do_load */, /*kit->control(),*/ access.base(), adr, adr_idx, val.node(),
! static_cast<const TypeOopPtr*>(val.type()), nullptr /* pre_val */, access.type());
! Node* result = BarrierSetC2::store_at_resolved(access, val);
! if (ShenandoahCardBarrier) {
! const bool anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0;
! const bool is_array = (decorators & IS_ARRAY) != 0;
! const bool use_precise = is_array || anonymous;
- post_barrier(kit, kit->control(), access.raw_access(), access.base(),
- adr, adr_idx, val.node(), access.type(), use_precise);
- }
- return result;
} else {
! assert(access.is_opt_access(), "only for optimization passes");
! assert(((decorators & C2_TIGHTLY_COUPLED_ALLOC) != 0 || !ShenandoahSATBBarrier) && (decorators & C2_ARRAY_COPY) != 0, "unexpected caller of this code");
! return BarrierSetC2::store_at_resolved(access, val);
}
}
Node* ShenandoahBarrierSetC2::load_at_resolved(C2Access& access, const Type* val_type) const {
// 1: non-reference load, no additional barrier is needed
if (!access.is_oop()) {
return BarrierSetC2::load_at_resolved(access, val_type);
}
! Node* load = BarrierSetC2::load_at_resolved(access, val_type);
! DecoratorSet decorators = access.decorators();
- BasicType type = access.type();
-
- // 2: apply LRB if needed
- if (ShenandoahBarrierSet::need_load_reference_barrier(decorators, type)) {
- load = new ShenandoahLoadReferenceBarrierNode(nullptr, load, decorators);
- if (access.is_parse_access()) {
- load = static_cast<C2ParseAccess &>(access).kit()->gvn().transform(load);
- } else {
- load = static_cast<C2OptAccess &>(access).gvn().transform(load);
- }
- }
! // 3: apply keep-alive barrier for java.lang.ref.Reference if needed
! if (ShenandoahBarrierSet::need_keep_alive_barrier(decorators, type)) {
! Node* top = Compile::current()->top();
! Node* adr = access.addr().node();
! Node* offset = adr->is_AddP() ? adr->in(AddPNode::Offset) : top;
! Node* obj = access.base();
!
! bool unknown = (decorators & ON_UNKNOWN_OOP_REF) != 0;
! bool on_weak_ref = (decorators & (ON_WEAK_OOP_REF | ON_PHANTOM_OOP_REF)) != 0;
! bool keep_alive = (decorators & AS_NO_KEEPALIVE) == 0;
!
! // 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.
- if (!on_weak_ref || (unknown && (offset == top || obj == top)) || !keep_alive) {
- return load;
- }
-
- assert(access.is_parse_access(), "entry not supported at optimization time");
- C2ParseAccess& parse_access = static_cast<C2ParseAccess&>(access);
- GraphKit* kit = parse_access.kit();
- bool mismatched = (decorators & C2_MISMATCHED) != 0;
- bool is_unordered = (decorators & MO_UNORDERED) != 0;
- bool in_native = (decorators & IN_NATIVE) != 0;
- bool need_cpu_mem_bar = !is_unordered || mismatched || in_native;
-
- if (on_weak_ref) {
- // Use the pre-barrier to record the value in the referent field
- satb_write_barrier_pre(kit, false /* do_load */,
- nullptr /* obj */, nullptr /* adr */, max_juint /* alias_idx */, nullptr /* val */, nullptr /* 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()) {
! shenandoah_write_barrier_pre(kit, false /* do_load */,
- nullptr, nullptr, max_juint, nullptr, nullptr,
- 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 = nullptr;
-
- #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(nullptr, load_store, access.decorators()));
- if (ShenandoahCardBarrier) {
- post_barrier(kit, kit->control(), access.raw_access(), access.base(),
- access.addr().node(), access.alias_idx(), new_val, T_OBJECT, true);
- }
- 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()) {
! shenandoah_write_barrier_pre(kit, false /* do_load */,
- nullptr, nullptr, max_juint, nullptr, nullptr,
- 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 = nullptr;
- 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);
- if (ShenandoahCardBarrier) {
- post_barrier(kit, kit->control(), access.raw_access(), access.base(),
- access.addr().node(), access.alias_idx(), new_val, T_OBJECT, true);
- }
- 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();
- Node* result = BarrierSetC2::atomic_xchg_at_resolved(access, val, value_type);
if (access.is_oop()) {
! result = kit->gvn().transform(new ShenandoahLoadReferenceBarrierNode(nullptr, result, access.decorators()));
- shenandoah_write_barrier_pre(kit, false /* do_load */,
- nullptr, nullptr, max_juint, nullptr, nullptr,
- result /* pre_val */, T_OBJECT);
- if (ShenandoahCardBarrier) {
- post_barrier(kit, kit->control(), access.raw_access(), access.base(),
- access.addr().node(), access.alias_idx(), val, T_OBJECT, true);
- }
}
! return result;
}
- bool ShenandoahBarrierSetC2::is_gc_pre_barrier_node(Node* node) const {
- return is_shenandoah_wb_pre_call(node);
- }
-
bool ShenandoahBarrierSetC2::is_gc_barrier_node(Node* node) const {
! return (node->Opcode() == Op_ShenandoahLoadReferenceBarrier) ||
- is_shenandoah_lrb_call(node) ||
- is_shenandoah_wb_pre_call(node) ||
- is_shenandoah_clone_call(node);
}
! Node* ShenandoahBarrierSetC2::step_over_gc_barrier(Node* c) const {
! if (c == nullptr) {
! return c;
}
! if (c->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
! return c->in(ShenandoahLoadReferenceBarrierNode::ValueIn);
}
! 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;
}
return false;
}
bool ShenandoahBarrierSetC2::array_copy_requires_gc_barriers(bool tightly_coupled_alloc, BasicType type, bool is_clone, bool is_clone_instance, ArrayCopyPhase phase) const {
const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+0, fields);
return TypeFunc::make(domain, range);
}
! static uint8_t get_store_barrier(C2Access& access) {
! if (!access.is_parse_access()) {
! // Only support for eliding barriers at parse time for now.
! return ShenandoahBarrierSATB | ShenandoahBarrierCardMark;
+ }
+ GraphKit* kit = (static_cast<C2ParseAccess&>(access)).kit();
+ Node* ctl = kit->control();
+ Node* adr = access.addr().node();
+ uint adr_idx = kit->C->get_alias_index(access.addr().type());
+ assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory");
! bool can_remove_pre_barrier = satb_can_remove_pre_barrier(kit, &kit->gvn(), adr, access.type(), adr_idx);
! // We can skip marks on a freshly-allocated object in Eden. Keep this code in
! // sync with CardTableBarrierSet::on_slowpath_allocation_exit. That routine
! // informs GC to take appropriate compensating steps, upon a slow-path
! // allocation, so as to make this card-mark elision safe.
+ // The post-barrier can also be removed if null is written. This case is
+ // handled by ShenandoahBarrierSetC2::expand_barriers, which runs at the end of C2's
+ // platform-independent optimizations to exploit stronger type information.
+ bool can_remove_post_barrier = ReduceInitialCardMarks &&
+ ((access.base() == kit->just_allocated_object(ctl)) ||
+ shenandoah_can_remove_post_barrier(kit, &kit->gvn(), ctl, adr));
! int barriers = 0;
+ if (!can_remove_pre_barrier) {
+ barriers |= ShenandoahBarrierSATB;
+ }
+ if (!can_remove_post_barrier) {
+ barriers |= ShenandoahBarrierCardMark;
+ }
+
+ return barriers;
}
Node* ShenandoahBarrierSetC2::store_at_resolved(C2Access& access, C2AccessValue& val) const {
DecoratorSet decorators = access.decorators();
! bool anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0;
! bool in_heap = (decorators & IN_HEAP) != 0;
! bool tightly_coupled_alloc = (decorators & C2_TIGHTLY_COUPLED_ALLOC) != 0;
! bool need_store_barrier = !(tightly_coupled_alloc && ReduceInitialCardMarks) && (in_heap || anonymous);
bool no_keepalive = (decorators & AS_NO_KEEPALIVE) != 0;
! if (access.is_oop() && need_store_barrier) {
! access.set_barrier_data(get_store_barrier(access));
! if (tightly_coupled_alloc) {
+ assert(!ReduceInitialCardMarks,
+ "post-barriers are only needed for tightly-coupled initialization stores when ReduceInitialCardMarks is disabled");
+ // Pre-barriers are unnecessary for tightly-coupled initialization stores.
+ access.set_barrier_data(access.barrier_data() & ~ShenandoahBarrierSATB);
+ }
}
if (no_keepalive) {
// No keep-alive means no need for the pre-barrier.
! access.set_barrier_data(access.barrier_data() & ~ShenandoahBarrierSATB);
}
+ return BarrierSetC2::store_at_resolved(access, val);
+ }
! static void set_barrier_data(C2Access& access) {
! if (!access.is_oop()) {
! return;
+ }
! if (access.decorators() & C2_TIGHTLY_COUPLED_ALLOC) {
! access.set_barrier_data(ShenandoahBarrierElided);
! return;
! }
! uint8_t barrier_data = 0;
! if (access.decorators() & ON_PHANTOM_OOP_REF) {
! barrier_data |= ShenandoahBarrierPhantom;
! } else if (access.decorators() & ON_WEAK_OOP_REF) {
! barrier_data |= ShenandoahBarrierWeak;
} else {
! barrier_data |= ShenandoahBarrierStrong;
! }
!
+ if (access.decorators() & IN_NATIVE) {
+ barrier_data |= ShenandoahBarrierNative;
}
+
+ access.set_barrier_data(barrier_data);
}
Node* ShenandoahBarrierSetC2::load_at_resolved(C2Access& access, const Type* val_type) const {
// 1: non-reference load, no additional barrier is needed
if (!access.is_oop()) {
return BarrierSetC2::load_at_resolved(access, val_type);
}
! // 2. Set barrier data for LRB.
! set_barrier_data(access);
! // 3. If we are reading the value of the referent field of a Reference object, we
! // need to record the referent in an SATB log buffer using the pre-barrier
! // mechanism.
! DecoratorSet decorators = access.decorators();
! bool on_weak = (decorators & ON_WEAK_OOP_REF) != 0;
! bool on_phantom = (decorators & ON_PHANTOM_OOP_REF) != 0;
! bool no_keepalive = (decorators & AS_NO_KEEPALIVE) != 0;
! // If we are reading the value of the referent field of a Reference object, we
! // need to record the referent in an SATB log buffer using the pre-barrier
! // mechanism. Also we need to add a memory barrier to prevent commoning reads
! // from this field across safepoints, since GC can change its value.
! uint8_t barriers = access.barrier_data();
! bool need_read_barrier = ((on_weak || on_phantom) && !no_keepalive);
! if (access.is_oop() && need_read_barrier) {
! barriers |= ShenandoahBarrierSATB;
}
+ access.set_barrier_data(barriers);
! return BarrierSetC2::load_at_resolved(access, val_type);
}
Node* ShenandoahBarrierSetC2::atomic_cmpxchg_val_at_resolved(C2AtomicParseAccess& access, Node* expected_val,
Node* new_val, const Type* value_type) const {
! if (ShenandoahCASBarrier) {
! set_barrier_data(access);
! }
! if (access.is_oop()) {
! access.set_barrier_data(access.barrier_data() | ShenandoahBarrierSATB | ShenandoahBarrierCardMark);
}
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 {
+ if (ShenandoahCASBarrier) {
+ set_barrier_data(access);
+ }
GraphKit* kit = access.kit();
if (access.is_oop()) {
! access.set_barrier_data(access.barrier_data() | ShenandoahBarrierSATB | ShenandoahBarrierCardMark);
}
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 {
if (access.is_oop()) {
! access.set_barrier_data(ShenandoahBarrierStrong | ShenandoahBarrierSATB | ShenandoahBarrierCardMark);
}
! return BarrierSetC2::atomic_xchg_at_resolved(access, val, value_type);
}
bool ShenandoahBarrierSetC2::is_gc_barrier_node(Node* node) const {
! return is_shenandoah_clone_call(node);
}
! static void refine_barrier_by_new_val_type(const Node* n) {
! if (n->Opcode() != Op_StoreP && n->Opcode() != Op_StoreN) {
! return;
+ }
+ MemNode* store = n->as_Mem();
+ const Node* newval = n->in(MemNode::ValueIn);
+ assert(newval != nullptr, "");
+ const Type* newval_bottom = newval->bottom_type();
+ TypePtr::PTR newval_type = newval_bottom->make_ptr()->ptr();
+ uint8_t barrier_data = store->barrier_data();
+ if (!newval_bottom->isa_oopptr() &&
+ !newval_bottom->isa_narrowoop() &&
+ newval_type != TypePtr::Null) {
+ // newval is neither an OOP nor null, so there is no barrier to refine.
+ assert(barrier_data == 0, "non-OOP stores should have no barrier data");
+ return;
+ }
+ if (barrier_data == 0) {
+ // No barrier to refine.
+ return;
}
! if (newval_type == TypePtr::Null) {
! // Simply elide post-barrier if writing null.
+ barrier_data &= ~ShenandoahBarrierCardMark;
+ barrier_data &= ~ShenandoahBarrierCardMarkNotNull;
+ } else if ((barrier_data & ShenandoahBarrierCardMark) != 0 &&
+ newval_type == TypePtr::NotNull) {
+ // If the post-barrier has not been elided yet (e.g. due to newval being
+ // freshly allocated), mark it as not-null (simplifies barrier tests and
+ // compressed OOPs logic).
+ barrier_data |= ShenandoahBarrierCardMarkNotNull;
}
! store->set_barrier_data(barrier_data);
}
bool ShenandoahBarrierSetC2::expand_barriers(Compile* C, PhaseIterGVN& igvn) const {
! ResourceMark rm;
! VectorSet visited;
! Node_List worklist;
! worklist.push(C->root());
! while (worklist.size() > 0) {
! Node* n = worklist.pop();
! if (visited.test_set(n->_idx)) {
! continue;
+ }
+ refine_barrier_by_new_val_type(n);
+ for (uint j = 0; j < n->req(); j++) {
+ Node* in = n->in(j);
+ if (in != nullptr) {
+ worklist.push(in);
+ }
+ }
}
return false;
}
bool ShenandoahBarrierSetC2::array_copy_requires_gc_barriers(bool tightly_coupled_alloc, BasicType type, bool is_clone, bool is_clone_instance, ArrayCopyPhase phase) const {
}
}
// Support for macro expanded GC barriers
! void ShenandoahBarrierSetC2::register_potential_barrier_node(Node* node) const {
! 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_ShenandoahLoadReferenceBarrier) {
- state()->remove_load_reference_barrier((ShenandoahLoadReferenceBarrierNode*) node);
}
}
void ShenandoahBarrierSetC2::eliminate_gc_barrier(PhaseMacroExpand* macro, Node* node) const {
! if (is_shenandoah_wb_pre_call(node)) {
- shenandoah_eliminate_wb_pre(node, ¯o->igvn());
- }
- if (ShenandoahCardBarrier && node->Opcode() == Op_CastP2X) {
- Node* shift = node->unique_out();
- Node* addp = shift->unique_out();
- for (DUIterator_Last jmin, j = addp->last_outs(jmin); j >= jmin; --j) {
- Node* mem = addp->last_out(j);
- if (UseCondCardMark && mem->is_Load()) {
- assert(mem->Opcode() == Op_LoadB, "unexpected code shape");
- // The load is checking if the card has been written so
- // replace it with zero to fold the test.
- macro->replace_node(mem, macro->intcon(0));
- continue;
- }
- assert(mem->is_Store(), "store required");
- macro->replace_node(mem, mem->in(MemNode::Memory));
- }
- }
- }
-
- 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()->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::create_barrier_state(Arena* comp_arena) const {
return new(comp_arena) ShenandoahBarrierSetC2State(comp_arena);
}
ShenandoahBarrierSetC2State* ShenandoahBarrierSetC2::state() const {
return reinterpret_cast<ShenandoahBarrierSetC2State*>(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::BeforeMacroExpand) {
- ShenandoahBarrierC2Support::verify(Compile::current()->root());
- } else if (phase == BarrierSetC2::BeforeCodeGen) {
- // Verify Shenandoah pre-barriers
- const int gc_state_offset = in_bytes(ShenandoahThreadLocalData::gc_state_offset());
-
- Unique_Node_List visited;
- Node_List worklist;
- // 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 == nullptr || 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() == gc_state_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_NeverBranch()) {
- if_ctrl = if_ctrl->in(0)->in(0);
- }
- }
- assert(load_ctrl != nullptr && 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_barrier_pre_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 one input is null, then step over the strong LRB barriers on the other input
- if (in1->bottom_type() == TypePtr::NULL_PTR &&
- !((in2->Opcode() == Op_ShenandoahLoadReferenceBarrier) &&
- !ShenandoahBarrierSet::is_strong_access(((ShenandoahLoadReferenceBarrierNode*)in2)->decorators()))) {
- in2 = step_over_gc_barrier(in2);
- }
- if (in2->bottom_type() == TypePtr::NULL_PTR &&
- !((in1->Opcode() == Op_ShenandoahLoadReferenceBarrier) &&
- !ShenandoahBarrierSet::is_strong_access(((ShenandoahLoadReferenceBarrierNode*)in1)->decorators()))) {
- in1 = step_over_gc_barrier(in1);
- }
! if (in1 != n->in(1)) {
! n->set_req_X(1, in1, phase);
! assert(in2 == n->in(2), "only one change");
! return n;
! }
! if (in2 != n->in(2)) {
! n->set_req_X(2, in2, phase);
- return n;
- }
- } else if (can_reshape &&
- n->Opcode() == Op_If &&
- ShenandoahBarrierC2Support::is_heap_stable_test(n) &&
- n->in(0) != nullptr &&
- n->outcnt() == 2) {
- 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 nullptr;
-
- dist--;
- prev_dom = dom;
- dom = IfNode::up_one_dom(dom);
- if (!dom) return nullptr;
- }
! // Check that we did not follow a loop back to ourselves
! if (n == dom) {
! return nullptr;
}
! return n->as_If()->dominated_by(prev_dom, phase->is_IterGVN(), false);
}
! return nullptr;
}
! 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::final_graph_reshaping(Compile* compile, Node* n, uint opcode, Unique_Node_List& dead_nodes) 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_barrier_pre_Type()->domain()->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:
- return true;
- case Op_ShenandoahLoadReferenceBarrier:
- assert(false, "should have been expanded already");
- return true;
- default:
- return false;
- }
}
! 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 Shenandoah 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_ShenandoahLoadReferenceBarrier:
- conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(ShenandoahLoadReferenceBarrierNode::ValueIn), delayed_worklist);
- return true;
- 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, nullptr);
- // 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_ShenandoahLoadReferenceBarrier:
- conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(ShenandoahLoadReferenceBarrierNode::ValueIn), nullptr);
- 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::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;
}
}
}
// Support for macro expanded GC barriers
! void ShenandoahBarrierSetC2::eliminate_gc_barrier_data(Node* node) const {
! if (node->is_LoadStore()) {
! LoadStoreNode* loadstore = node->as_LoadStore();
! loadstore->set_barrier_data(0);
! } else if (node->is_Mem()) {
! MemNode* mem = node->as_Mem();
! mem->set_barrier_data(0);
}
}
void ShenandoahBarrierSetC2::eliminate_gc_barrier(PhaseMacroExpand* macro, Node* node) const {
! eliminate_gc_barrier_data(node);
}
void* ShenandoahBarrierSetC2::create_barrier_state(Arena* comp_arena) const {
return new(comp_arena) ShenandoahBarrierSetC2State(comp_arena);
}
ShenandoahBarrierSetC2State* ShenandoahBarrierSetC2::state() const {
return reinterpret_cast<ShenandoahBarrierSetC2State*>(Compile::current()->barrier_set_state());
}
#ifdef ASSERT
void ShenandoahBarrierSetC2::verify_gc_barriers(Compile* compile, CompilePhase phase) const {
! // TODO: Re-implement C2 barrier verification.
}
#endif
! static ShenandoahBarrierSetC2State* barrier_set_state() {
! return reinterpret_cast<ShenandoahBarrierSetC2State*>(Compile::current()->barrier_set_state());
! }
!
! int ShenandoahBarrierSetC2::estimate_stub_size() const {
! Compile* const C = Compile::current();
! BufferBlob* const blob = C->output()->scratch_buffer_blob();
! GrowableArray<ShenandoahBarrierStubC2*>* const stubs = barrier_set_state()->stubs();
! int size = 0;
!
! for (int i = 0; i < stubs->length(); i++) {
! CodeBuffer cb(blob->content_begin(), checked_cast<CodeBuffer::csize_t>((address)C->output()->scratch_locs_memory() - blob->content_begin()));
! MacroAssembler masm(&cb);
+ stubs->at(i)->emit_code(masm);
+ size += cb.insts_size();
}
! return size;
! }
!
! void ShenandoahBarrierSetC2::emit_stubs(CodeBuffer& cb) const {
! MacroAssembler masm(&cb);
! GrowableArray<ShenandoahBarrierStubC2*>* const stubs = barrier_set_state()->stubs();
! barrier_set_state()->set_stubs_start_offset(masm.offset());
! for (int i = 0; i < stubs->length(); i++) {
! // Make sure there is enough space in the code buffer
! if (cb.insts()->maybe_expand_to_ensure_remaining(PhaseOutput::MAX_inst_size) && cb.blob() == nullptr) {
+ ciEnv::current()->record_failure("CodeCache is full");
+ return;
}
! stubs->at(i)->emit_code(masm);
}
! masm.flush();
+
}
! void ShenandoahBarrierStubC2::register_stub() {
! if (!Compile::current()->output()->in_scratch_emit_size()) {
! barrier_set_state()->stubs()->append(this);
}
}
! ShenandoahLoadRefBarrierStubC2* ShenandoahLoadRefBarrierStubC2::create(const MachNode* node, Register obj, Register addr, Register tmp1, Register tmp2, Register tmp3, bool narrow) {
! auto* stub = new (Compile::current()->comp_arena()) ShenandoahLoadRefBarrierStubC2(node, obj, addr, tmp1, tmp2, tmp3, narrow);
! stub->register_stub();
! return stub;
}
! ShenandoahSATBBarrierStubC2* ShenandoahSATBBarrierStubC2::create(const MachNode* node, Register addr, Register preval, Register tmp) {
! auto* stub = new (Compile::current()->comp_arena()) ShenandoahSATBBarrierStubC2(node, addr, preval, tmp);
! stub->register_stub();
! return stub;
}
! ShenandoahCASBarrierSlowStubC2* ShenandoahCASBarrierSlowStubC2::create(const MachNode* node, Register addr, Register expected, Register new_val, Register result, Register tmp, bool cae, bool acquire, bool release, bool weak) {
! auto* stub = new (Compile::current()->comp_arena()) ShenandoahCASBarrierSlowStubC2(node, addr, Address(), expected, new_val, result, tmp, noreg, cae, acquire, release, weak);
! stub->register_stub();
! return stub;
}
! ShenandoahCASBarrierSlowStubC2* ShenandoahCASBarrierSlowStubC2::create(const MachNode* node, Address addr, Register expected, Register new_val, Register result, Register tmp1, Register tmp2, bool cae) {
! auto* stub = new (Compile::current()->comp_arena()) ShenandoahCASBarrierSlowStubC2(node, noreg, addr, expected, new_val, result, tmp1, tmp2, cae, false, false, false);
! stub->register_stub();
+ return stub;
+ }
+ ShenandoahCASBarrierMidStubC2* ShenandoahCASBarrierMidStubC2::create(const MachNode* node, ShenandoahCASBarrierSlowStubC2* slow_stub, Register expected, Register result, Register tmp, bool cae) {
+ auto* stub = new (Compile::current()->comp_arena()) ShenandoahCASBarrierMidStubC2(node, slow_stub, expected, result, tmp, cae);
+ stub->register_stub();
+ return stub;
}
! bool ShenandoahBarrierSetC2State::needs_liveness_data(const MachNode* mach) const {
! //assert(mach->barrier_data() != 0, "what else?");
! // return mach->barrier_data() != 0;
! //return (mach->barrier_data() & ShenandoahSATBBarrier) != 0;
! return ShenandoahSATBBarrierStubC2::needs_barrier(mach) || ShenandoahLoadRefBarrierStubC2::needs_barrier(mach);
}
! bool ShenandoahBarrierSetC2State::needs_livein_data() const {
! return true;
}
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