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Quellcode-Bibliothek© Kompilation durch diese Firma[Weder Korrektheit noch Funktionsfähigkeit der Software werden zugesichert.]Datei: Sprache: C |
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/*
* Copyright (c) 2005, 2022, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "compiler/compileLog.hpp" #include "gc/shared/collectedHeap.inline.hpp" #include "gc/shared/tlab_globals.hpp" #include "libadt/vectset.hpp" #include "memory/universe.hpp" #include "opto/addnode.hpp" #include "opto/arraycopynode.hpp" #include "opto/callnode.hpp" #include "opto/castnode.hpp" #include "opto/cfgnode.hpp" #include "opto/compile.hpp" #include "opto/convertnode.hpp" #include "opto/graphKit.hpp" #include "opto/intrinsicnode.hpp" #include "opto/locknode.hpp" #include "opto/loopnode.hpp" #include "opto/macro.hpp" #include "opto/memnode.hpp" #include "opto/narrowptrnode.hpp" #include "opto/node.hpp" #include "opto/opaquenode.hpp" #include "opto/phaseX.hpp" #include "opto/rootnode.hpp" #include "opto/runtime.hpp" #include "opto/subnode.hpp" #include "opto/subtypenode.hpp" #include "opto/type.hpp" #include "prims/jvmtiExport.hpp" #include "runtime/continuation.hpp" #include "runtime/sharedRuntime.hpp" #include "utilities/macros.hpp" #include "utilities/powerOfTwo.hpp" #if INCLUDE_G1GC #include "gc/g1/g1ThreadLocalData.hpp" #endif // INCLUDE_G1GC // // Replace any references to "oldref" in inputs to "use" with "newref". // Returns the number of replacements made. // int PhaseMacroExpand::replace_input(Node *use, Node *oldref, Node *newref) { int nreplacements = 0; uint req = use->req(); for (uint j = 0; j < use->len(); j++) { Node *uin = use->in(j); if (uin == oldref) { if (j < req) use->set_req(j, newref); else use->set_prec(j, newref); nreplacements++; } else if (j >= req && uin == NULL) { break; } } return nreplacements; } void PhaseMacroExpand::migrate_outs(Node *old, Node *target) { assert(old != NULL, "sanity"); for (DUIterator_Fast imax, i = old->fast_outs(imax); i < imax; i++) { Node* use = old->fast_out(i); _igvn.rehash_node_delayed(use); imax -= replace_input(use, old, target); // back up iterator --i; } assert(old->outcnt() == 0, "all uses must be deleted"); } Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word, int Node* cmp; if (mask != 0) { Node* and_node = transform_later(new AndXNode(word, MakeConX(mask))); cmp = transform_later(new CmpXNode(and_node, MakeConX(bits))); } else { cmp = word; } Node* bol = transform_later(new BoolNode(cmp, BoolTest::ne)); IfNode* iff = new IfNode( ctrl, bol, PROB_MIN, COUNT_UNKNOWN ); transform_later(iff); // Fast path taken. Node *fast_taken = transform_later(new IfFalseNode(iff)); // Fast path not-taken, i.e. slow path Node *slow_taken = transform_later(new IfTrueNode(iff)); if (return_fast_path) { region->init_req(edge, slow_taken); // Capture slow-control return fast_taken; } else { region->init_req(edge, fast_taken); // Capture fast-control return slow_taken; } } //--------------------copy_predefined_input_for_runtime_call-------------------- void PhaseMacroExpand::copy_predefined_input_for_runtime_call(Node * ctrl, CallNode* // Set fixed predefined input arguments call->init_req( TypeFunc::Control, ctrl ); call->init_req( TypeFunc::I_O , oldcall->in( TypeFunc::I_O) ); call->init_req( TypeFunc::Memory , oldcall->in( TypeFunc::Memory ) ); // ????? call->init_req( TypeFunc::ReturnAdr, oldcall->in( TypeFunc::ReturnAdr ) ); call->init_req( TypeFunc::FramePtr, oldcall->in( TypeFunc::FramePtr ) ); } //------------------------------make_slow_call--------------------------------- CallNode* PhaseMacroExpand::make_slow_call(CallNode *oldcall, const TypeFunc* slow_ca address slow_call, const char* leaf_name, Node* slow_path, Node* parm0, Node* parm1, Node* parm2) { // Slow-path call CallNode *call = leaf_name ? (CallNode*)new CallLeafNode ( slow_call_type, slow_call, leaf_name, TypeRawPtr::BOTTO : (CallNode*)new CallStaticJavaNode( slow_call_type, slow_call, OptoRuntime::stub_nam // Slow path call has no side-effects, uses few values copy_predefined_input_for_runtime_call(slow_path, oldcall, call ); if (parm0 != NULL) call->init_req(TypeFunc::Parms+0, parm0); if (parm1 != NULL) call->init_req(TypeFunc::Parms+1, parm1); if (parm2 != NULL) call->init_req(TypeFunc::Parms+2, parm2); call->copy_call_debug_info(&_igvn, oldcall); call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON. _igvn.replace_node(oldcall, call); transform_later(call); return call; } void PhaseMacroExpand::eliminate_gc_barrier(Node* p2x) { BarrierSetC2 *bs = BarrierSet::barrier_set()->barrier_set_c2(); bs->eliminate_gc_barrier(this, p2x); #ifndef PRODUCT if (PrintOptoStatistics) { Atomic::inc(&PhaseMacroExpand::_GC_barriers_removed_counter); } #endif } // Search for a memory operation for the specified memory slice. static Node *scan_mem_chain(Node *mem, int alias_idx, int offset, Node *start_mem, Node *al Node *orig_mem = mem; Node *alloc_mem = alloc->in(TypeFunc::Memory); const TypeOopPtr *tinst = phase->C->get_adr_type(alias_idx)->isa_oopptr(); while (true) { if (mem == alloc_mem || mem == start_mem ) { return mem; // hit one of our sentinels } else if (mem->is_MergeMem()) { mem = mem->as_MergeMem()->memory_at(alias_idx); } else if (mem->is_Proj() && mem->as_Proj()->_con == TypeFunc::Memory) { Node *in = mem->in(0); // we can safely skip over safepoints, calls, locks and membars because we // already know that the object is safe to eliminate. if (in->is_Initialize() && in->as_Initialize()->allocation() == alloc) { return in; } else if (in->is_Call()) { CallNode *call = in->as_Call(); if (call->may_modify(tinst, phase)) { assert(call->is_ArrayCopy(), "ArrayCopy is the only call node that doesn't make al if (call->as_ArrayCopy()->modifies(offset, offset, phase, false)) { return in; } } mem = in->in(TypeFunc::Memory); } else if (in->is_MemBar()) { ArrayCopyNode* ac = NULL; if (ArrayCopyNode::may_modify(tinst, in->as_MemBar(), phase, ac)) { if (ac != NULL) { assert(ac->is_clonebasic(), "Only basic clone is a non escaping clone"); return ac; } } mem = in->in(TypeFunc::Memory); } else { #ifdef ASSERT in->dump(); mem->dump(); assert(false, "unexpected projection"); #endif } } else if (mem->is_Store()) { const TypePtr* atype = mem->as_Store()->adr_type(); int adr_idx = phase->C->get_alias_index(atype); if (adr_idx == alias_idx) { assert(atype->isa_oopptr(), "address type must be oopptr"); int adr_offset = atype->offset(); uint adr_iid = atype->is_oopptr()->instance_id(); // Array elements references have the same alias_idx // but different offset and different instance_id. if (adr_offset == offset && adr_iid == alloc->_idx) { return mem; } } else { assert(adr_idx == Compile::AliasIdxRaw, "address must match or be raw"); } mem = mem->in(MemNode::Memory); } else if (mem->is_ClearArray()) { if (!ClearArrayNode::step_through(&mem, alloc->_idx, phase)) { // Can not bypass initialization of the instance // we are looking. debug_only(intptr_t offset;) assert(alloc == AllocateNode::Ideal_allocation(mem->in(3), phase, offset), "sanity"); InitializeNode* init = alloc->as_Allocate()->initialization(); // We are looking for stored value, return Initialize node // or memory edge from Allocate node. if (init != NULL) { return init; } else { return alloc->in(TypeFunc::Memory); // It will produce zero value (see callers). } } // Otherwise skip it (the call updated 'mem' value). } else if (mem->Opcode() == Op_SCMemProj) { mem = mem->in(0); Node* adr = NULL; if (mem->is_LoadStore()) { adr = mem->in(MemNode::Address); } else { assert(mem->Opcode() == Op_EncodeISOArray || mem->Opcode() == Op_StrCompressedCopy, "sanity"); adr = mem->in(3); // Destination array } const TypePtr* atype = adr->bottom_type()->is_ptr(); int adr_idx = phase->C->get_alias_index(atype); if (adr_idx == alias_idx) { DEBUG_ONLY(mem->dump();) assert(false, "Object is not scalar replaceable if a LoadStore node accesses its return NULL; } mem = mem->in(MemNode::Memory); } else if (mem->Opcode() == Op_StrInflatedCopy) { Node* adr = mem->in(3); // Destination array const TypePtr* atype = adr->bottom_type()->is_ptr(); int adr_idx = phase->C->get_alias_index(atype); if (adr_idx == alias_idx) { DEBUG_ONLY(mem->dump();) assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesse return NULL; } mem = mem->in(MemNode::Memory); } else { return mem; } assert(mem != orig_mem, "dead memory loop"); } } // Generate loads from source of the arraycopy for fields of // destination needed at a deoptimization point Node* PhaseMacroExpand::make_arraycopy_load(ArrayCopyNode* ac, intptr_t offset, Node* BasicType bt = ft; const Type *type = ftype; if (ft == T_NARROWOOP) { bt = T_OBJECT; type = ftype->make_oopptr(); } Node* res = NULL; if (ac->is_clonebasic()) { assert(ac->in(ArrayCopyNode::Src) != ac->in(ArrayCopyNode::Dest), "clone source equal Node* base = ac->in(ArrayCopyNode::Src); Node* adr = _igvn.transform(new AddPNode(base, base, MakeConX(offset))); const TypePtr* adr_type = _igvn.type(base)->is_ptr()->add_offset(offset); MergeMemNode* mergemen = _igvn.transform(MergeMemNode::make(mem))->as_MergeMem(); BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); res = ArrayCopyNode::load(bs, &_igvn, ctl, mergemen, adr, adr_type, type, bt); } else { if (ac->modifies(offset, offset, &_igvn, true)) { assert(ac->in(ArrayCopyNode::Dest) == alloc->result_cast(), "arraycopy destination sh uint shift = exact_log2(type2aelembytes(bt)); Node* src_pos = ac->in(ArrayCopyNode::SrcPos); Node* dest_pos = ac->in(ArrayCopyNode::DestPos); const TypeInt* src_pos_t = _igvn.type(src_pos)->is_int(); const TypeInt* dest_pos_t = _igvn.type(dest_pos)->is_int(); Node* adr = NULL; const TypePtr* adr_type = NULL; if (src_pos_t->is_con() && dest_pos_t->is_con()) { intptr_t off = ((src_pos_t->get_con() - dest_pos_t->get_con()) << shift) + offset; Node* base = ac->in(ArrayCopyNode::Src); adr = _igvn.transform(new AddPNode(base, base, MakeConX(off))); adr_type = _igvn.type(base)->is_ptr()->add_offset(off); if (ac->in(ArrayCopyNode::Src) == ac->in(ArrayCopyNode::Dest)) { // Don't emit a new load from src if src == dst but try to get the value from memory instead return value_from_mem(ac->in(TypeFunc::Memory), ctl, ft, ftype, adr_type->isa_oopptr(), } } else { Node* diff = _igvn.transform(new SubINode(ac->in(ArrayCopyNode::SrcPos), ac->in(ArrayCo #ifdef _LP64 diff = _igvn.transform(new ConvI2LNode(diff)); #endif diff = _igvn.transform(new LShiftXNode(diff, intcon(shift))); Node* off = _igvn.transform(new AddXNode(MakeConX(offset), diff)); Node* base = ac->in(ArrayCopyNode::Src); adr = _igvn.transform(new AddPNode(base, base, off)); adr_type = _igvn.type(base)->is_ptr()->add_offset(Type::OffsetBot); if (ac->in(ArrayCopyNode::Src) == ac->in(ArrayCopyNode::Dest)) { // Non constant offset in the array: we can't statically // determine the value return NULL; } } MergeMemNode* mergemen = _igvn.transform(MergeMemNode::make(mem))->as_MergeMem(); BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); res = ArrayCopyNode::load(bs, &_igvn, ctl, mergemen, adr, adr_type, type, bt); } } if (res != NULL) { if (ftype->isa_narrowoop()) { // PhaseMacroExpand::scalar_replacement adds DecodeN nodes res = _igvn.transform(new EncodePNode(res, ftype)); } return res; } return NULL; } // // Given a Memory Phi, compute a value Phi containing the values from stores // on the input paths. // Note: this function is recursive, its depth is limited by the "level" argument // Returns the computed Phi, or NULL if it cannot compute it. Node *PhaseMacroExpand::value_from_mem_phi(Node *mem, BasicType ft, const Type *phi_typ assert(mem->is_Phi(), "sanity"); int alias_idx = C->get_alias_index(adr_t); int offset = adr_t->offset(); int instance_id = adr_t->instance_id(); // Check if an appropriate value phi already exists. Node* region = mem->in(0); for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) { Node* phi = region->fast_out(k); if (phi->is_Phi() && phi != mem && phi->as_Phi()->is_same_inst_field(phi_type, (int)mem->_idx, instance_id, alias_idx, off return phi; } } // Check if an appropriate new value phi already exists. Node* new_phi = value_phis->find(mem->_idx); if (new_phi != NULL) return new_phi; if (level <= 0) { return NULL; // Give up: phi tree too deep } Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory); Node *alloc_mem = alloc->in(TypeFunc::Memory); uint length = mem->req(); GrowableArray <Node *> values(length, length, NULL); // create a new Phi for the value PhiNode *phi = new PhiNode(mem->in(0), phi_type, NULL, mem->_idx, instance_id, alias_idx, of transform_later(phi); value_phis->push(phi, mem->_idx); for (uint j = 1; j < length; j++) { Node *in = mem->in(j); if (in == NULL || in->is_top()) { values.at_put(j, in); } else { Node *val = scan_mem_chain(in, alias_idx, offset, start_mem, alloc, &_igvn); if (val == start_mem || val == alloc_mem) { // hit a sentinel, return appropriate 0 value values.at_put(j, _igvn.zerocon(ft)); continue; } if (val->is_Initialize()) { val = val->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn); } if (val == NULL) { return NULL; // can't find a value on this path } if (val == mem) { values.at_put(j, mem); } else if (val->is_Store()) { Node* n = val->in(MemNode::ValueIn); BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); n = bs->step_over_gc_barrier(n); if (is_subword_type(ft)) { n = Compile::narrow_value(ft, n, phi_type, &_igvn, true); } values.at_put(j, n); } else if(val->is_Proj() && val->in(0) == alloc) { values.at_put(j, _igvn.zerocon(ft)); } else if (val->is_Phi()) { val = value_from_mem_phi(val, ft, phi_type, adr_t, alloc, value_phis, level-1); if (val == NULL) { return NULL; } values.at_put(j, val); } else if (val->Opcode() == Op_SCMemProj) { assert(val->in(0)->is_LoadStore() || val->in(0)->Opcode() == Op_EncodeISOArray || val->in(0)->Opcode() == Op_StrCompressedCopy, "sanity"); assert(false, "Object is not scalar replaceable if a LoadStore node accesses its return NULL; } else if (val->is_ArrayCopy()) { Node* res = make_arraycopy_load(val->as_ArrayCopy(), offset, val->in(0), val->in(TypeFunc if (res == NULL) { return NULL; } values.at_put(j, res); } else { DEBUG_ONLY( val->dump(); ) assert(false, "unknown node on this path"); return NULL; // unknown node on this path } } } // Set Phi's inputs for (uint j = 1; j < length; j++) { if (values.at(j) == mem) { phi->init_req(j, phi); } else { phi->init_req(j, values.at(j)); } } return phi; } // Search the last value stored into the object's field. Node *PhaseMacroExpand::value_from_mem(Node *sfpt_mem, Node *sfpt_ctl, BasicType ft, co assert(adr_t->is_known_instance_field(), "instance required"); int instance_id = adr_t->instance_id(); assert((uint)instance_id == alloc->_idx, "wrong allocation"); int alias_idx = C->get_alias_index(adr_t); int offset = adr_t->offset(); Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory); Node *alloc_ctrl = alloc->in(TypeFunc::Control); Node *alloc_mem = alloc->in(TypeFunc::Memory); VectorSet visited; bool done = sfpt_mem == alloc_mem; Node *mem = sfpt_mem; while (!done) { if (visited.test_set(mem->_idx)) { return NULL; // found a loop, give up } mem = scan_mem_chain(mem, alias_idx, offset, start_mem, alloc, &_igvn); if (mem == start_mem || mem == alloc_mem) { done = true; // hit a sentinel, return appropriate 0 value } else if (mem->is_Initialize()) { mem = mem->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn); if (mem == NULL) { done = true; // Something go wrong. } else if (mem->is_Store()) { const TypePtr* atype = mem->as_Store()->adr_type(); assert(C->get_alias_index(atype) == Compile::AliasIdxRaw, "store is correct memory s done = true; } } else if (mem->is_Store()) { const TypeOopPtr* atype = mem->as_Store()->adr_type()->isa_oopptr(); assert(atype != NULL, "address type must be oopptr"); assert(C->get_alias_index(atype) == alias_idx && atype->is_known_instance_field() && atype->offset() == offset && atype->instance_id() == instance_id, "store is correct memory slice"); done = true; } else if (mem->is_Phi()) { // try to find a phi's unique input Node *unique_input = NULL; Node *top = C->top(); for (uint i = 1; i < mem->req(); i++) { Node *n = scan_mem_chain(mem->in(i), alias_idx, offset, start_mem, alloc, &_igvn); if (n == NULL || n == top || n == mem) { continue; } else if (unique_input == NULL) { unique_input = n; } else if (unique_input != n) { unique_input = top; break; } } if (unique_input != NULL && unique_input != top) { mem = unique_input; } else { done = true; } } else if (mem->is_ArrayCopy()) { done = true; } else { DEBUG_ONLY( mem->dump(); ) assert(false, "unexpected node"); } } if (mem != NULL) { if (mem == start_mem || mem == alloc_mem) { // hit a sentinel, return appropriate 0 value return _igvn.zerocon(ft); } else if (mem->is_Store()) { Node* n = mem->in(MemNode::ValueIn); BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); n = bs->step_over_gc_barrier(n); return n; } else if (mem->is_Phi()) { // attempt to produce a Phi reflecting the values on the input paths of the Phi Node_Stack value_phis(8); Node* phi = value_from_mem_phi(mem, ft, ftype, adr_t, alloc, &value_phis, ValueSearchLimit); if (phi != NULL) { return phi; } else { // Kill all new Phis while(value_phis.is_nonempty()) { Node* n = value_phis.node(); _igvn.replace_node(n, C->top()); value_phis.pop(); } } } else if (mem->is_ArrayCopy()) { Node* ctl = mem->in(0); Node* m = mem->in(TypeFunc::Memory); if (sfpt_ctl->is_Proj() && sfpt_ctl->as_Proj()->is_uncommon_trap_proj(Deoptimization::Re // pin the loads in the uncommon trap path ctl = sfpt_ctl; m = sfpt_mem; } return make_arraycopy_load(mem->as_ArrayCopy(), offset, ctl, m, ft, ftype, alloc); } } // Something go wrong. return NULL; } // Check the possibility of scalar replacement. bool PhaseMacroExpand::can_eliminate_allocation(AllocateNode *alloc, GrowableArray <S // Scan the uses of the allocation to check for anything that would // prevent us from eliminating it. NOT_PRODUCT( const char* fail_eliminate = NULL; ) DEBUG_ONLY( Node* disq_node = NULL; ) bool can_eliminate = true; Node* res = alloc->result_cast(); const TypeOopPtr* res_type = NULL; if (res == NULL) { // All users were eliminated. } else if (!res->is_CheckCastPP()) { NOT_PRODUCT(fail_eliminate = "Allocation does not have unique CheckCastPP";) can_eliminate = false; } else { res_type = _igvn.type(res)->isa_oopptr(); if (res_type == NULL) { NOT_PRODUCT(fail_eliminate = "Neither instance or array allocation";) can_eliminate = false; } else if (res_type->isa_aryptr()) { int length = alloc->in(AllocateNode::ALength)->find_int_con(-1); if (length < 0) { NOT_PRODUCT(fail_eliminate = "Array's size is not constant";) can_eliminate = false; } } } if (can_eliminate && res != NULL) { BarrierSetC2 *bs = BarrierSet::barrier_set()->barrier_set_c2(); for (DUIterator_Fast jmax, j = res->fast_outs(jmax); j < jmax && can_eliminate; j++) { Node* use = res->fast_out(j); if (use->is_AddP()) { const TypePtr* addp_type = _igvn.type(use)->is_ptr(); int offset = addp_type->offset(); if (offset == Type::OffsetTop || offset == Type::OffsetBot) { NOT_PRODUCT(fail_eliminate = "Undefined field reference";) can_eliminate = false; break; } for (DUIterator_Fast kmax, k = use->fast_outs(kmax); k < kmax && can_eliminate; k++) { Node* n = use->fast_out(k); if (!n->is_Store() && n->Opcode() != Op_CastP2X && !bs->is_gc_pre_barrier_node(n)) { DEBUG_ONLY(disq_node = n;) if (n->is_Load() || n->is_LoadStore()) { NOT_PRODUCT(fail_eliminate = "Field load";) } else { NOT_PRODUCT(fail_eliminate = "Not store field reference";) } can_eliminate = false; } } } else if (use->is_ArrayCopy() && (use->as_ArrayCopy()->is_clonebasic() || use->as_ArrayCopy()->is_arraycopy_validated() || use->as_ArrayCopy()->is_copyof_validated() || use->as_ArrayCopy()->is_copyofrange_validated()) && use->in(ArrayCopyNode::Dest) == res) { // ok to eliminate } else if (use->is_SafePoint()) { SafePointNode* sfpt = use->as_SafePoint(); if (sfpt->is_Call() && sfpt->as_Call()->has_non_debug_use(res)) { // Object is passed as argument. DEBUG_ONLY(disq_node = use;) NOT_PRODUCT(fail_eliminate = "Object is passed as argument";) can_eliminate = false; } Node* sfptMem = sfpt->memory(); if (sfptMem == NULL || sfptMem->is_top()) { DEBUG_ONLY(disq_node = use;) NOT_PRODUCT(fail_eliminate = "NULL or TOP memory";) can_eliminate = false; } else { safepoints.append_if_missing(sfpt); } } else if (use->Opcode() != Op_CastP2X) { // CastP2X is used by card mark if (use->is_Phi()) { if (use->outcnt() == 1 && use->unique_out()->Opcode() == Op_Return) { NOT_PRODUCT(fail_eliminate = "Object is return value";) } else { NOT_PRODUCT(fail_eliminate = "Object is referenced by Phi";) } DEBUG_ONLY(disq_node = use;) } else { if (use->Opcode() == Op_Return) { NOT_PRODUCT(fail_eliminate = "Object is return value";) }else { NOT_PRODUCT(fail_eliminate = "Object is referenced by node";) } DEBUG_ONLY(disq_node = use;) } can_eliminate = false; } } } #ifndef PRODUCT if (PrintEliminateAllocations) { if (can_eliminate) { tty->print("Scalar "); if (res == NULL) alloc->dump(); else res->dump(); } else if (alloc->_is_scalar_replaceable) { tty->print("NotScalar (%s)", fail_eliminate); if (res == NULL) alloc->dump(); else res->dump(); #ifdef ASSERT if (disq_node != NULL) { tty->print(" >>>> "); disq_node->dump(); } #endif /*ASSERT*/ } } #endif return can_eliminate; } // Do scalar replacement. bool PhaseMacroExpand::scalar_replacement(AllocateNode *alloc, GrowableArray <SafePoi GrowableArray <SafePointNode *> safepoints_done; ciInstanceKlass* iklass = NULL; int nfields = 0; int array_base = 0; int element_size = 0; BasicType basic_elem_type = T_ILLEGAL; const Type* field_type = NULL; Node* res = alloc->result_cast(); assert(res == NULL || res->is_CheckCastPP(), "unexpected AllocateNode result"); const TypeOopPtr* res_type = NULL; if (res != NULL) { // Could be NULL when there are no users res_type = _igvn.type(res)->isa_oopptr(); } if (res != NULL) { if (res_type->isa_instptr()) { // find the fields of the class which will be needed for safepoint debug information iklass = res_type->is_instptr()->instance_klass(); nfields = iklass->nof_nonstatic_fields(); } else { // find the array's elements which will be needed for safepoint debug information nfields = alloc->in(AllocateNode::ALength)->find_int_con(-1); assert(nfields >= 0, "must be an array klass."); basic_elem_type = res_type->is_aryptr()->elem()->array_element_basic_type(); array_base = arrayOopDesc::base_offset_in_bytes(basic_elem_type); element_size = type2aelembytes(basic_elem_type); field_type = res_type->is_aryptr()->elem(); } } // // Process the safepoint uses // while (safepoints.length() > 0) { SafePointNode* sfpt = safepoints.pop(); Node* mem = sfpt->memory(); Node* ctl = sfpt->control(); assert(sfpt->jvms() != NULL, "missed JVMS"); // Fields of scalar objs are referenced only at the end // of regular debuginfo at the last (youngest) JVMS. // Record relative start index. uint first_ind = (sfpt->req() - sfpt->jvms()->scloff()); SafePointScalarObjectNode* sobj = new SafePointScalarObjectNode(res_type, #ifdef ASSERT alloc, #endif first_ind, nfields); sobj->init_req(0, C->root()); transform_later(sobj); // Scan object's fields adding an input to the safepoint for each field. for (int j = 0; j < nfields; j++) { intptr_t offset; ciField* field = NULL; if (iklass != NULL) { field = iklass->nonstatic_field_at(j); offset = field->offset(); ciType* elem_type = field->type(); basic_elem_type = field->layout_type(); // The next code is taken from Parse::do_get_xxx(). if (is_reference_type(basic_elem_type)) { if (!elem_type->is_loaded()) { field_type = TypeInstPtr::BOTTOM; } else if (field != NULL && field->is_static_constant()) { ciObject* con = field->constant_value().as_object(); // Do not "join" in the previous type; it doesn't add value, // and may yield a vacuous result if the field is of interface type. field_type = TypeOopPtr::make_from_constant(con)->isa_oopptr(); assert(field_type != NULL, "field singleton type must be consistent"); } else { field_type = TypeOopPtr::make_from_klass(elem_type->as_klass()); } if (UseCompressedOops) { field_type = field_type->make_narrowoop(); basic_elem_type = T_NARROWOOP; } } else { field_type = Type::get_const_basic_type(basic_elem_type); } } else { offset = array_base + j * (intptr_t)element_size; } const TypeOopPtr *field_addr_type = res_type->add_offset(offset)->isa_oopptr(); Node *field_val = value_from_mem(mem, ctl, basic_elem_type, field_type, field_addr_type if (field_val == NULL) { // We weren't able to find a value for this field, // give up on eliminating this allocation. // Remove any extra entries we added to the safepoint. uint last = sfpt->req() - 1; for (int k = 0; k < j; k++) { sfpt->del_req(last--); } _igvn._worklist.push(sfpt); // rollback processed safepoints while (safepoints_done.length() > 0) { SafePointNode* sfpt_done = safepoints_done.pop(); // remove any extra entries we added to the safepoint last = sfpt_done->req() - 1; for (int k = 0; k < nfields; k++) { sfpt_done->del_req(last--); } JVMState *jvms = sfpt_done->jvms(); jvms->set_endoff(sfpt_done->req()); // Now make a pass over the debug information replacing any references // to SafePointScalarObjectNode with the allocated object. int start = jvms->debug_start(); int end = jvms->debug_end(); for (int i = start; i < end; i++) { if (sfpt_done->in(i)->is_SafePointScalarObject()) { SafePointScalarObjectNode* scobj = sfpt_done->in(i)->as_SafePointScalarObject(); if (scobj->first_index(jvms) == sfpt_done->req() && scobj->n_fields() == (uint)nfields) { assert(scobj->alloc() == alloc, "sanity"); sfpt_done->set_req(i, res); } } } _igvn._worklist.push(sfpt_done); } #ifndef PRODUCT if (PrintEliminateAllocations) { if (field != NULL) { tty->print("=== At SafePoint node %d can't find value of Field: ", sfpt->_idx); field->print(); int field_idx = C->get_alias_index(field_addr_type); tty->print(" (alias_idx=%d)", field_idx); } else { // Array's element tty->print("=== At SafePoint node %d can't find value of array element [%d]", sfpt->_idx, j); } tty->print(", which prevents elimination of: "); if (res == NULL) alloc->dump(); else res->dump(); } #endif return false; } if (UseCompressedOops && field_type->isa_narrowoop()) { // Enable "DecodeN(EncodeP(Allocate)) --> Allocate" transformation // to be able scalar replace the allocation. if (field_val->is_EncodeP()) { field_val = field_val->in(1); } else { field_val = transform_later(new DecodeNNode(field_val, field_val->get_ptr_type())); } } sfpt->add_req(field_val); } JVMState *jvms = sfpt->jvms(); jvms->set_endoff(sfpt->req()); // Now make a pass over the debug information replacing any references // to the allocated object with "sobj" int start = jvms->debug_start(); int end = jvms->debug_end(); sfpt->replace_edges_in_range(res, sobj, start, end, &_igvn); _igvn._worklist.push(sfpt); safepoints_done.append_if_missing(sfpt); // keep it for rollback } return true; } static void disconnect_projections(MultiNode* n, PhaseIterGVN& igvn) { Node* ctl_proj = n->proj_out_or_null(TypeFunc::Control); Node* mem_proj = n->proj_out_or_null(TypeFunc::Memory); if (ctl_proj != NULL) { igvn.replace_node(ctl_proj, n->in(0)); } if (mem_proj != NULL) { igvn.replace_node(mem_proj, n->in(TypeFunc::Memory)); } } // Process users of eliminated allocation. void PhaseMacroExpand::process_users_of_allocation(CallNode *alloc) { Node* res = alloc->result_cast(); if (res != NULL) { for (DUIterator_Last jmin, j = res->last_outs(jmin); j >= jmin; ) { Node *use = res->last_out(j); uint oc1 = res->outcnt(); if (use->is_AddP()) { for (DUIterator_Last kmin, k = use->last_outs(kmin); k >= kmin; ) { Node *n = use->last_out(k); uint oc2 = use->outcnt(); if (n->is_Store()) { #ifdef ASSERT // Verify that there is no dependent MemBarVolatile nodes, // they should be removed during IGVN, see MemBarNode::Ideal(). for (DUIterator_Fast pmax, p = n->fast_outs(pmax); p < pmax; p++) { Node* mb = n->fast_out(p); assert(mb->is_Initialize() || !mb->is_MemBar() || mb->req() <= MemBarNode::Precedent || mb->in(MemBarNode::Precedent) != n, "MemBarVolatile should be eliminated for non-escaping object"); } #endif _igvn.replace_node(n, n->in(MemNode::Memory)); } else { eliminate_gc_barrier(n); } k -= (oc2 - use->outcnt()); } _igvn.remove_dead_node(use); } else if (use->is_ArrayCopy()) { // Disconnect ArrayCopy node ArrayCopyNode* ac = use->as_ArrayCopy(); if (ac->is_clonebasic()) { Node* membar_after = ac->proj_out(TypeFunc::Control)->unique_ctrl_out(); disconnect_projections(ac, _igvn); assert(alloc->in(TypeFunc::Memory)->is_Proj() && alloc->in(TypeFunc::Memory)->in(0)->Opco Node* membar_before = alloc->in(TypeFunc::Memory)->in(0); disconnect_projections(membar_before->as_MemBar(), _igvn); if (membar_after->is_MemBar()) { disconnect_projections(membar_after->as_MemBar(), _igvn); } } else { assert(ac->is_arraycopy_validated() || ac->is_copyof_validated() || ac->is_copyofrange_validated(), "unsupported"); CallProjections callprojs; ac->extract_projections(&callprojs, true); _igvn.replace_node(callprojs.fallthrough_ioproj, ac->in(TypeFunc::I_O)); _igvn.replace_node(callprojs.fallthrough_memproj, ac->in(TypeFunc::Memory)); _igvn.replace_node(callprojs.fallthrough_catchproj, ac->in(TypeFunc::Control)); // Set control to top. IGVN will remove the remaining projections ac->set_req(0, top()); ac->replace_edge(res, top(), &_igvn); // Disconnect src right away: it can help find new // opportunities for allocation elimination Node* src = ac->in(ArrayCopyNode::Src); ac->replace_edge(src, top(), &_igvn); // src can be top at this point if src and dest of the // arraycopy were the same if (src->outcnt() == 0 && !src->is_top()) { _igvn.remove_dead_node(src); } } _igvn._worklist.push(ac); } else { eliminate_gc_barrier(use); } j -= (oc1 - res->outcnt()); } assert(res->outcnt() == 0, "all uses of allocated objects must be deleted"); _igvn.remove_dead_node(res); } // // Process other users of allocation's projections // if (_callprojs.resproj != NULL && _callprojs.resproj->outcnt() != 0) { // First disconnect stores captured by Initialize node. // If Initialize node is eliminated first in the following code, // it will kill such stores and DUIterator_Last will assert. for (DUIterator_Fast jmax, j = _callprojs.resproj->fast_outs(jmax); j < jmax; j++) { Node* use = _callprojs.resproj->fast_out(j); if (use->is_AddP()) { // raw memory addresses used only by the initialization _igvn.replace_node(use, C->top()); --j; --jmax; } } for (DUIterator_Last jmin, j = _callprojs.resproj->last_outs(jmin); j >= jmin; ) { Node* use = _callprojs.resproj->last_out(j); uint oc1 = _callprojs.resproj->outcnt(); if (use->is_Initialize()) { // Eliminate Initialize node. InitializeNode *init = use->as_Initialize(); assert(init->outcnt() <= 2, "only a control and memory projection expected"); Node *ctrl_proj = init->proj_out_or_null(TypeFunc::Control); if (ctrl_proj != NULL) { _igvn.replace_node(ctrl_proj, init->in(TypeFunc::Control)); #ifdef ASSERT // If the InitializeNode has no memory out, it will die, and tmp will become NULL Node* tmp = init->in(TypeFunc::Control); assert(tmp == NULL || tmp == _callprojs.fallthrough_catchproj, "allocation control proj #endif } Node *mem_proj = init->proj_out_or_null(TypeFunc::Memory); if (mem_proj != NULL) { Node *mem = init->in(TypeFunc::Memory); #ifdef ASSERT if (mem->is_MergeMem()) { assert(mem->in(TypeFunc::Memory) == _callprojs.fallthrough_memproj, "allocation memo } else { assert(mem == _callprojs.fallthrough_memproj, "allocation memory projection"); } #endif _igvn.replace_node(mem_proj, mem); } } else { assert(false, "only Initialize or AddP expected"); } j -= (oc1 - _callprojs.resproj->outcnt()); } } if (_callprojs.fallthrough_catchproj != NULL) { _igvn.replace_node(_callprojs.fallthrough_catchproj, alloc->in(TypeFunc::Control)) } if (_callprojs.fallthrough_memproj != NULL) { _igvn.replace_node(_callprojs.fallthrough_memproj, alloc->in(TypeFunc::Memory)); } if (_callprojs.catchall_memproj != NULL) { _igvn.replace_node(_callprojs.catchall_memproj, C->top()); } if (_callprojs.fallthrough_ioproj != NULL) { _igvn.replace_node(_callprojs.fallthrough_ioproj, alloc->in(TypeFunc::I_O)); } if (_callprojs.catchall_ioproj != NULL) { _igvn.replace_node(_callprojs.catchall_ioproj, C->top()); } if (_callprojs.catchall_catchproj != NULL) { _igvn.replace_node(_callprojs.catchall_catchproj, C->top()); } } bool PhaseMacroExpand::eliminate_allocate_node(AllocateNode *alloc) { // If reallocation fails during deoptimization we'll pop all // interpreter frames for this compiled frame and that won't play // nice with JVMTI popframe. // We avoid this issue by eager reallocation when the popframe request // is received. if (!EliminateAllocations || !alloc->_is_non_escaping) { return false; } Node* klass = alloc->in(AllocateNode::KlassNode); const TypeKlassPtr* tklass = _igvn.type(klass)->is_klassptr(); Node* res = alloc->result_cast(); // Eliminate boxing allocations which are not used // regardless scalar replaceable status. bool boxing_alloc = C->eliminate_boxing() && tklass->isa_instklassptr() && tklass->is_instklassptr()->instance_klass()->is_box_klass(); if (!alloc->_is_scalar_replaceable && (!boxing_alloc || (res != NULL))) { return false; } alloc->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); GrowableArray <SafePointNode *> safepoints; if (!can_eliminate_allocation(alloc, safepoints)) { return false; } if (!alloc->_is_scalar_replaceable) { assert(res == NULL, "sanity"); // We can only eliminate allocation if all debug info references // are already replaced with SafePointScalarObject because // we can't search for a fields value without instance_id. if (safepoints.length() > 0) { return false; } } if (!scalar_replacement(alloc, safepoints)) { return false; } CompileLog* log = C->log(); if (log != NULL) { log->head("eliminate_allocation type='%d'", log->identify(tklass->exact_klass())); JVMState* p = alloc->jvms(); while (p != NULL) { log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method())); p = p->caller(); } log->tail("eliminate_allocation"); } process_users_of_allocation(alloc); #ifndef PRODUCT if (PrintEliminateAllocations) { if (alloc->is_AllocateArray()) tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx); else tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx); } #endif return true; } bool PhaseMacroExpand::eliminate_boxing_node(CallStaticJavaNode *boxing) { // EA should remove all uses of non-escaping boxing node. if (!C->eliminate_boxing() || boxing->proj_out_or_null(TypeFunc::Parms) != NULL) { return false; } assert(boxing->result_cast() == NULL, "unexpected boxing node result"); boxing->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); const TypeTuple* r = boxing->tf()->range(); assert(r->cnt() > TypeFunc::Parms, "sanity"); const TypeInstPtr* t = r->field_at(TypeFunc::Parms)->isa_instptr(); assert(t != NULL, "sanity"); CompileLog* log = C->log(); if (log != NULL) { log->head("eliminate_boxing type='%d'", log->identify(t->instance_klass())); JVMState* p = boxing->jvms(); while (p != NULL) { log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method())); p = p->caller(); } log->tail("eliminate_boxing"); } process_users_of_allocation(boxing); #ifndef PRODUCT if (PrintEliminateAllocations) { tty->print("++++ Eliminated: %d ", boxing->_idx); boxing->method()->print_short_name(tty); tty->cr(); } #endif return true; } Node* PhaseMacroExpand::make_load(Node* ctl, Node* mem, Node* base, int offset, const Type Node* adr = basic_plus_adr(base, offset); const TypePtr* adr_type = adr->bottom_type()->is_ptr(); Node* value = LoadNode::make(_igvn, ctl, mem, adr, adr_type, value_type, bt, MemNode::unor transform_later(value); return value; } Node* PhaseMacroExpand::make_store(Node* ctl, Node* mem, Node* base, int offset, Node* val Node* adr = basic_plus_adr(base, offset); mem = StoreNode::make(_igvn, ctl, mem, adr, NULL, value, bt, MemNode::unordered); transform_later(mem); return mem; } //============================================================================= // // A L L O C A T I O N // // Allocation attempts to be fast in the case of frequent small objects. // It breaks down like this: // // 1) Size in doublewords is computed. This is a constant for objects and // variable for most arrays. Doubleword units are used to avoid size // overflow of huge doubleword arrays. We need doublewords in the end for // rounding. // // 2) Size is checked for being 'too large'. Too-large allocations will go // the slow path into the VM. The slow path can throw any required // exceptions, and does all the special checks for very large arrays. The // size test can constant-fold away for objects. For objects with // finalizers it constant-folds the otherway: you always go slow with // finalizers. // // 3) If NOT using TLABs, this is the contended loop-back point. // Load-Locked the heap top. If using TLABs normal-load the heap top. // // 4) Check that heap top + size*8 < max. If we fail go the slow ` route. // NOTE: "top+size*8" cannot wrap the 4Gig line! Here's why: for largish // "size*8" we always enter the VM, where "largish" is a constant picked small // enough that there's always space between the eden max and 4Gig (old space is // there so it's quite large) and large enough that the cost of entering the VM // is dwarfed by the cost to initialize the space. // // 5) If NOT using TLABs, Store-Conditional the adjusted heap top back // down. If contended, repeat at step 3. If using TLABs normal-store // adjusted heap top back down; there is no contention. // // 6) If !ZeroTLAB then Bulk-clear the object/array. Fill in klass & mark // fields. // // 7) Merge with the slow-path; cast the raw memory pointer to the correct // oop flavor. // //============================================================================= // FastAllocateSizeLimit value is in DOUBLEWORDS. // Allocations bigger than this always go the slow route. // This value must be small enough that allocation attempts that need to // trigger exceptions go the slow route. Also, it must be small enough so // that heap_top + size_in_bytes does not wrap around the 4Gig limit. //=============================================================================j // %%% Here is an old comment from parseHelper.cpp; is it outdated? // The allocator will coalesce int->oop copies away. See comment in // coalesce.cpp about how this works. It depends critically on the exact // code shape produced here, so if you are changing this code shape // make sure the GC info for the heap-top is correct in and around the // slow-path call. // void PhaseMacroExpand::expand_allocate_common( AllocateNode* alloc, // allocation node to be expanded Node* length, // array length for an array allocation const TypeFunc* slow_call_type, // Type of slow call address slow_call_address, // Address of slow call Node* valid_length_test // whether length is valid or not ) { Node* ctrl = alloc->in(TypeFunc::Control); Node* mem = alloc->in(TypeFunc::Memory); Node* i_o = alloc->in(TypeFunc::I_O); Node* size_in_bytes = alloc->in(AllocateNode::AllocSize); Node* klass_node = alloc->in(AllocateNode::KlassNode); Node* initial_slow_test = alloc->in(AllocateNode::InitialTest); assert(ctrl != NULL, "must have control"); // We need a Region and corresponding Phi's to merge the slow-path and fast-path results. // they will not be used if "always_slow" is set enum { slow_result_path = 1, fast_result_path = 2 }; Node *result_region = NULL; Node *result_phi_rawmem = NULL; Node *result_phi_rawoop = NULL; Node *result_phi_i_o = NULL; // The initial slow comparison is a size check, the comparison // we want to do is a BoolTest::gt bool expand_fast_path = true; int tv = _igvn.find_int_con(initial_slow_test, -1); if (tv >= 0) { // InitialTest has constant result // 0 - can fit in TLAB // 1 - always too big or negative assert(tv <= 1, "0 or 1 if a constant"); expand_fast_path = (tv == 0); initial_slow_test = NULL; } else { initial_slow_test = BoolNode::make_predicate(initial_slow_test, &_igvn); } if (!UseTLAB) { // Force slow-path allocation expand_fast_path = false; initial_slow_test = NULL; } bool allocation_has_use = (alloc->result_cast() != NULL); if (!allocation_has_use) { InitializeNode* init = alloc->initialization(); if (init != NULL) { init->remove(&_igvn); } if (expand_fast_path && (initial_slow_test == NULL)) { // Remove allocation node and return. // Size is a non-negative constant -> no initial check needed -> directly to fast path. // Also, no usages -> empty fast path -> no fall out to slow path -> nothing left. #ifndef PRODUCT if (PrintEliminateAllocations) { tty->print("NotUsed "); Node* res = alloc->proj_out_or_null(TypeFunc::Parms); if (res != NULL) { res->dump(); } else { alloc->dump(); } } #endif yank_alloc_node(alloc); return; } } enum { too_big_or_final_path = 1, need_gc_path = 2 }; Node *slow_region = NULL; Node *toobig_false = ctrl; // generate the initial test if necessary if (initial_slow_test != NULL ) { assert (expand_fast_path, "Only need test if there is a fast path"); slow_region = new RegionNode(3); // Now make the initial failure test. Usually a too-big test but // might be a TRUE for finalizers or a fancy class check for // newInstance0. IfNode *toobig_iff = new IfNode(ctrl, initial_slow_test, PROB_MIN, COUNT_UNKNOWN); transform_later(toobig_iff); // Plug the failing-too-big test into the slow-path region Node *toobig_true = new IfTrueNode( toobig_iff ); transform_later(toobig_true); slow_region ->init_req( too_big_or_final_path, toobig_true ); toobig_false = new IfFalseNode( toobig_iff ); transform_later(toobig_false); } else { // No initial test, just fall into next case assert(allocation_has_use || !expand_fast_path, "Should already have been handled") toobig_false = ctrl; debug_only(slow_region = NodeSentinel); } // If we are here there are several possibilities // - expand_fast_path is false - then only a slow path is expanded. That's it. // no_initial_check means a constant allocation. // - If check always evaluates to false -> expand_fast_path is false (see above) // - If check always evaluates to true -> directly into fast path (but may bailout to slowpath) // if !allocation_has_use the fast path is empty // if !allocation_has_use && no_initial_check // - Then there are no fastpath that can fall out to slowpath -> no allocation code at all. // removed by yank_alloc_node above. Node *slow_mem = mem; // save the current memory state for slow path // generate the fast allocation code unless we know that the initial test will always go slow if (expand_fast_path) { // Fast path modifies only raw memory. if (mem->is_MergeMem()) { mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw); } // allocate the Region and Phi nodes for the result result_region = new RegionNode(3); result_phi_rawmem = new PhiNode(result_region, Type::MEMORY, TypeRawPtr::BOTTOM); result_phi_i_o = new PhiNode(result_region, Type::ABIO); // I/O is used for Prefetch // Grab regular I/O before optional prefetch may change it. // Slow-path does no I/O so just set it to the original I/O. result_phi_i_o->init_req(slow_result_path, i_o); // Name successful fast-path variables Node* fast_oop_ctrl; Node* fast_oop_rawmem; if (allocation_has_use) { Node* needgc_ctrl = NULL; result_phi_rawoop = new PhiNode(result_region, TypeRawPtr::BOTTOM); intx prefetch_lines = length != NULL ? AllocatePrefetchLines : AllocateInstancePrefetchLi BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); Node* fast_oop = bs->obj_allocate(this, mem, toobig_false, size_in_bytes, i_o, needgc_ctr fast_oop_ctrl, fast_oop_rawmem, prefetch_lines); if (initial_slow_test != NULL) { // This completes all paths into the slow merge point slow_region->init_req(need_gc_path, needgc_ctrl); transform_later(slow_region); } else { // No initial slow path needed! // Just fall from the need-GC path straight into the VM call. slow_region = needgc_ctrl; } InitializeNode* init = alloc->initialization(); fast_oop_rawmem = initialize_object(alloc, fast_oop_ctrl, fast_oop_rawmem, fast_oop, klass_node, length, size_in_bytes); expand_initialize_membar(alloc, init, fast_oop_ctrl, fast_oop_rawmem); expand_dtrace_alloc_probe(alloc, fast_oop, fast_oop_ctrl, fast_oop_rawmem); result_phi_rawoop->init_req(fast_result_path, fast_oop); } else { assert (initial_slow_test != NULL, "sanity"); fast_oop_ctrl = toobig_false; fast_oop_rawmem = mem; transform_later(slow_region); } // Plug in the successful fast-path into the result merge point result_region ->init_req(fast_result_path, fast_oop_ctrl); result_phi_i_o ->init_req(fast_result_path, i_o); result_phi_rawmem->init_req(fast_result_path, fast_oop_rawmem); } else { slow_region = ctrl; result_phi_i_o = i_o; // Rename it to use in the following code. } // Generate slow-path call CallNode *call = new CallStaticJavaNode(slow_call_type, slow_call_address, OptoRuntime::stub_name(slow_call_address), TypePtr::BOTTOM); call->init_req(TypeFunc::Control, slow_region); call->init_req(TypeFunc::I_O, top()); // does no i/o call->init_req(TypeFunc::Memory, slow_mem); // may gc ptrs call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr)); call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr)); call->init_req(TypeFunc::Parms+0, klass_node); if (length != NULL) { call->init_req(TypeFunc::Parms+1, length); } // Copy debug information and adjust JVMState information, then replace // allocate node with the call call->copy_call_debug_info(&_igvn, alloc); // For array allocations, copy the valid length check to the call node so Compile::final_graph // that the call has the expected number of CatchProj nodes (in case the allocation always fails // path dies). if (valid_length_test != NULL) { call->add_req(valid_length_test); } if (expand_fast_path) { call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON. } else { // Hook i_o projection to avoid its elimination during allocation // replacement (when only a slow call is generated). call->set_req(TypeFunc::I_O, result_phi_i_o); } _igvn.replace_node(alloc, call); transform_later(call); // Identify the output projections from the allocate node and // adjust any references to them. // The control and io projections look like: // // v---Proj(ctrl) <-----+ v---CatchProj(ctrl) // Allocate Catch // ^---Proj(io) <-------+ ^---CatchProj(io) // // We are interested in the CatchProj nodes. // call->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); // An allocate node has separate memory projections for the uses on // the control and i_o paths. Replace the control memory projection with // result_phi_rawmem (unless we are only generating a slow call when // both memory projections are combined) if (expand_fast_path && _callprojs.fallthrough_memproj != NULL) { migrate_outs(_callprojs.fallthrough_memproj, result_phi_rawmem); } // Now change uses of catchall_memproj to use fallthrough_memproj and delete // catchall_memproj so we end up with a call that has only 1 memory projection. if (_callprojs.catchall_memproj != NULL ) { if (_callprojs.fallthrough_memproj == NULL) { _callprojs.fallthrough_memproj = new ProjNode(call, TypeFunc::Memory); transform_later(_callprojs.fallthrough_memproj); } migrate_outs(_callprojs.catchall_memproj, _callprojs.fallthrough_memproj); _igvn.remove_dead_node(_callprojs.catchall_memproj); } // An allocate node has separate i_o projections for the uses on the control // and i_o paths. Always replace the control i_o projection with result i_o // otherwise incoming i_o become dead when only a slow call is generated // (it is different from memory projections where both projections are // combined in such case). if (_callprojs.fallthrough_ioproj != NULL) { migrate_outs(_callprojs.fallthrough_ioproj, result_phi_i_o); } // Now change uses of catchall_ioproj to use fallthrough_ioproj and delete // catchall_ioproj so we end up with a call that has only 1 i_o projection. if (_callprojs.catchall_ioproj != NULL ) { if (_callprojs.fallthrough_ioproj == NULL) { _callprojs.fallthrough_ioproj = new ProjNode(call, TypeFunc::I_O); transform_later(_callprojs.fallthrough_ioproj); } migrate_outs(_callprojs.catchall_ioproj, _callprojs.fallthrough_ioproj); _igvn.remove_dead_node(_callprojs.catchall_ioproj); } // if we generated only a slow call, we are done if (!expand_fast_path) { // Now we can unhook i_o. if (result_phi_i_o->outcnt() > 1) { call->set_req(TypeFunc::I_O, top()); } else { assert(result_phi_i_o->unique_ctrl_out() == call, "sanity"); // Case of new array with negative size known during compilation. // AllocateArrayNode::Ideal() optimization disconnect unreachable // following code since call to runtime will throw exception. // As result there will be no users of i_o after the call. // Leave i_o attached to this call to avoid problems in preceding graph. } return; } if (_callprojs.fallthrough_catchproj != NULL) { ctrl = _callprojs.fallthrough_catchproj->clone(); transform_later(ctrl); _igvn.replace_node(_callprojs.fallthrough_catchproj, result_region); } else { ctrl = top(); } Node *slow_result; if (_callprojs.resproj == NULL) { // no uses of the allocation result slow_result = top(); } else { slow_result = _callprojs.resproj->clone(); transform_later(slow_result); _igvn.replace_node(_callprojs.resproj, result_phi_rawoop); } // Plug slow-path into result merge point result_region->init_req( slow_result_path, ctrl); transform_later(result_region); if (allocation_has_use) { result_phi_rawoop->init_req(slow_result_path, slow_result); transform_later(result_phi_rawoop); } result_phi_rawmem->init_req(slow_result_path, _callprojs.fallthrough_memproj); transform_later(result_phi_rawmem); transform_later(result_phi_i_o); // This completes all paths into the result merge point } // Remove alloc node that has no uses. void PhaseMacroExpand::yank_alloc_node(AllocateNode* alloc) { Node* ctrl = alloc->in(TypeFunc::Control); Node* mem = alloc->in(TypeFunc::Memory); Node* i_o = alloc->in(TypeFunc::I_O); alloc->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/); if (_callprojs.resproj != NULL) { for (DUIterator_Fast imax, i = _callprojs.resproj->fast_outs(imax); i < imax; i++) { Node* use = _callprojs.resproj->fast_out(i); use->isa_MemBar()->remove(&_igvn); --imax; --i; // back up iterator } assert(_callprojs.resproj->outcnt() == 0, "all uses must be deleted"); _igvn.remove_dead_node(_callprojs.resproj); } if (_callprojs.fallthrough_catchproj != NULL) { migrate_outs(_callprojs.fallthrough_catchproj, ctrl); _igvn.remove_dead_node(_callprojs.fallthrough_catchproj); } if (_callprojs.catchall_catchproj != NULL) { _igvn.rehash_node_delayed(_callprojs.catchall_catchproj); _callprojs.catchall_catchproj->set_req(0, top()); } if (_callprojs.fallthrough_proj != NULL) { Node* catchnode = _callprojs.fallthrough_proj->unique_ctrl_out(); _igvn.remove_dead_node(catchnode); _igvn.remove_dead_node(_callprojs.fallthrough_proj); } if (_callprojs.fallthrough_memproj != NULL) { migrate_outs(_callprojs.fallthrough_memproj, mem); _igvn.remove_dead_node(_callprojs.fallthrough_memproj); } if (_callprojs.fallthrough_ioproj != NULL) { migrate_outs(_callprojs.fallthrough_ioproj, i_o); _igvn.remove_dead_node(_callprojs.fallthrough_ioproj); } if (_callprojs.catchall_memproj != NULL) { _igvn.rehash_node_delayed(_callprojs.catchall_memproj); _callprojs.catchall_memproj->set_req(0, top()); } if (_callprojs.catchall_ioproj != NULL) { _igvn.rehash_node_delayed(_callprojs.catchall_ioproj); _callprojs.catchall_ioproj->set_req(0, top()); } #ifndef PRODUCT if (PrintEliminateAllocations) { if (alloc->is_AllocateArray()) { tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx); } else { tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx); } } #endif _igvn.remove_dead_node(alloc); } void PhaseMacroExpand::expand_initialize_membar(AllocateNode* alloc, InitializeNode Node*& fast_oop_ctrl, Node*& fast_oop_rawmem) { // If initialization is performed by an array copy, any required // MemBarStoreStore was already added. If the object does not // escape no need for a MemBarStoreStore. If the object does not // escape in its initializer and memory barrier (MemBarStoreStore or // stronger) is already added at exit of initializer, also no need // for a MemBarStoreStore. Otherwise we need a MemBarStoreStore // so that stores that initialize this object can't be reordered // with a subsequent store that makes this object accessible by // other threads. // Other threads include java threads and JVM internal threads // (for example concurrent GC threads). Current concurrent GC // implementation: G1 will not scan newly created object, // so it's safe to skip storestore barrier when allocation does // not escape. if (!alloc->does_not_escape_thread() && !alloc->is_allocation_MemBar_redundant() && (init == NULL || !init->is_complete_with_arraycopy())) { if (init == NULL || init->req() < InitializeNode::RawStores) { // No InitializeNode or no stores captured by zeroing // elimination. Simply add the MemBarStoreStore after object // initialization. MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot); transform_later(mb); mb->init_req(TypeFunc::Memory, fast_oop_rawmem); mb->init_req(TypeFunc::Control, fast_oop_ctrl); fast_oop_ctrl = new ProjNode(mb, TypeFunc::Control); transform_later(fast_oop_ctrl); fast_oop_rawmem = new ProjNode(mb, TypeFunc::Memory); transform_later(fast_oop_rawmem); } else { // Add the MemBarStoreStore after the InitializeNode so that // all stores performing the initialization that were moved // before the InitializeNode happen before the storestore // barrier. Node* init_ctrl = init->proj_out_or_null(TypeFunc::Control); Node* init_mem = init->proj_out_or_null(TypeFunc::Memory); MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot); transform_later(mb); Node* ctrl = new ProjNode(init, TypeFunc::Control); transform_later(ctrl); Node* mem = new ProjNode(init, TypeFunc::Memory); transform_later(mem); // The MemBarStoreStore depends on control and memory coming // from the InitializeNode mb->init_req(TypeFunc::Memory, mem); mb->init_req(TypeFunc::Control, ctrl); ctrl = new ProjNode(mb, TypeFunc::Control); transform_later(ctrl); mem = new ProjNode(mb, TypeFunc::Memory); transform_later(mem); // All nodes that depended on the InitializeNode for control // and memory must now depend on the MemBarNode that itself // depends on the InitializeNode if (init_ctrl != NULL) { _igvn.replace_node(init_ctrl, ctrl); } if (init_mem != NULL) { _igvn.replace_node(init_mem, mem); } } } } void PhaseMacroExpand::expand_dtrace_alloc_probe(AllocateNode* alloc, Node* oop, Node*& ctrl, Node*& rawmem) { if (C->env()->dtrace_alloc_probes()) { // Slow-path call int size = TypeFunc::Parms + 2; CallLeafNode *call = new CallLeafNode(OptoRuntime::dtrace_object_alloc_Type(), CAST_FROM_FN_PTR(address, static_cast<int (*)(JavaThread*, oopDesc*)>(SharedRuntime::dtrace_object_alloc)), "dtrace_object_alloc", TypeRawPtr::BOTTOM); // Get base of thread-local storage area Node* thread = new ThreadLocalNode(); transform_later(thread); call->init_req(TypeFunc::Parms + 0, thread); call->init_req(TypeFunc::Parms + 1, oop); call->init_req(TypeFunc::Control, ctrl); --> -------------------- --> maximum size reached --> -------------------- ¤ Dauer der Verarbeitung: 0.101 Sekunden (vorverarbeitet) ¤ |
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