/* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "ci/bcEscapeAnalyzer.hpp" #include "libadt/vectset.hpp" #include "memory/allocation.hpp" #include "opto/c2compiler.hpp" #include "opto/callnode.hpp" #include "opto/cfgnode.hpp" #include "opto/compile.hpp" #include "opto/escape.hpp" #include "opto/phaseX.hpp" #include "opto/rootnode.hpp" void PointsToNode::add_edge(uint targIdx, PointsToNode::EdgeType et) { uint v = (targIdx << EdgeShift) + ((uint) et); if (_edges == NULL) { Arena *a = Compile::current()->comp_arena(); _edges = new(a) GrowableArray(a, INITIAL_EDGE_COUNT, 0, 0); } _edges->append_if_missing(v); } void PointsToNode::remove_edge(uint targIdx, PointsToNode::EdgeType et) { uint v = (targIdx << EdgeShift) + ((uint) et); _edges->remove(v); } #ifndef PRODUCT static const char *node_type_names[] = { "UnknownType", "JavaObject", "LocalVar", "Field" }; static const char *esc_names[] = { "UnknownEscape", "NoEscape", "ArgEscape", "GlobalEscape" }; static const char *edge_type_suffix[] = { "?", // UnknownEdge "P", // PointsToEdge "D", // DeferredEdge "F" // FieldEdge }; void PointsToNode::dump(bool print_state) const { NodeType nt = node_type(); tty->print("%s ", node_type_names[(int) nt]); if (print_state) { EscapeState es = escape_state(); tty->print("%s %s ", esc_names[(int) es], _scalar_replaceable ? "":"NSR"); } tty->print("[["); for (uint i = 0; i < edge_count(); i++) { tty->print(" %d%s", edge_target(i), edge_type_suffix[(int) edge_type(i)]); } tty->print("]] "); if (_node == NULL) tty->print_cr(""); else _node->dump(); } #endif ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn) : _nodes(C->comp_arena(), C->unique(), C->unique(), PointsToNode()), _processed(C->comp_arena()), _collecting(true), _compile(C), _igvn(igvn), _node_map(C->comp_arena()) { _phantom_object = C->top()->_idx, add_node(C->top(), PointsToNode::JavaObject, PointsToNode::GlobalEscape,true); // Add ConP(#NULL) and ConN(#NULL) nodes. Node* oop_null = igvn->zerocon(T_OBJECT); _oop_null = oop_null->_idx; assert(_oop_null < C->unique(), "should be created already"); add_node(oop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true); if (UseCompressedOops) { Node* noop_null = igvn->zerocon(T_NARROWOOP); _noop_null = noop_null->_idx; assert(_noop_null < C->unique(), "should be created already"); add_node(noop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true); } } void ConnectionGraph::add_pointsto_edge(uint from_i, uint to_i) { PointsToNode *f = ptnode_adr(from_i); PointsToNode *t = ptnode_adr(to_i); assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set"); assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of PointsTo edge"); assert(t->node_type() == PointsToNode::JavaObject, "invalid destination of PointsTo edge"); f->add_edge(to_i, PointsToNode::PointsToEdge); } void ConnectionGraph::add_deferred_edge(uint from_i, uint to_i) { PointsToNode *f = ptnode_adr(from_i); PointsToNode *t = ptnode_adr(to_i); assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set"); assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of Deferred edge"); assert(t->node_type() == PointsToNode::LocalVar || t->node_type() == PointsToNode::Field, "invalid destination of Deferred edge"); // don't add a self-referential edge, this can occur during removal of // deferred edges if (from_i != to_i) f->add_edge(to_i, PointsToNode::DeferredEdge); } int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) { const Type *adr_type = phase->type(adr); if (adr->is_AddP() && adr_type->isa_oopptr() == NULL && adr->in(AddPNode::Address)->is_Proj() && adr->in(AddPNode::Address)->in(0)->is_Allocate()) { // We are computing a raw address for a store captured by an Initialize // compute an appropriate address type. AddP cases #3 and #5 (see below). int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); assert(offs != Type::OffsetBot || adr->in(AddPNode::Address)->in(0)->is_AllocateArray(), "offset must be a constant or it is initialization of array"); return offs; } const TypePtr *t_ptr = adr_type->isa_ptr(); assert(t_ptr != NULL, "must be a pointer type"); return t_ptr->offset(); } void ConnectionGraph::add_field_edge(uint from_i, uint to_i, int offset) { PointsToNode *f = ptnode_adr(from_i); PointsToNode *t = ptnode_adr(to_i); assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set"); assert(f->node_type() == PointsToNode::JavaObject, "invalid destination of Field edge"); assert(t->node_type() == PointsToNode::Field, "invalid destination of Field edge"); assert (t->offset() == -1 || t->offset() == offset, "conflicting field offsets"); t->set_offset(offset); f->add_edge(to_i, PointsToNode::FieldEdge); } void ConnectionGraph::set_escape_state(uint ni, PointsToNode::EscapeState es) { PointsToNode *npt = ptnode_adr(ni); PointsToNode::EscapeState old_es = npt->escape_state(); if (es > old_es) npt->set_escape_state(es); } void ConnectionGraph::add_node(Node *n, PointsToNode::NodeType nt, PointsToNode::EscapeState es, bool done) { PointsToNode* ptadr = ptnode_adr(n->_idx); ptadr->_node = n; ptadr->set_node_type(nt); // inline set_escape_state(idx, es); PointsToNode::EscapeState old_es = ptadr->escape_state(); if (es > old_es) ptadr->set_escape_state(es); if (done) _processed.set(n->_idx); } PointsToNode::EscapeState ConnectionGraph::escape_state(Node *n) { uint idx = n->_idx; PointsToNode::EscapeState es; // If we are still collecting or there were no non-escaping allocations // we don't know the answer yet if (_collecting) return PointsToNode::UnknownEscape; // if the node was created after the escape computation, return // UnknownEscape if (idx >= nodes_size()) return PointsToNode::UnknownEscape; es = ptnode_adr(idx)->escape_state(); // if we have already computed a value, return it if (es != PointsToNode::UnknownEscape && ptnode_adr(idx)->node_type() == PointsToNode::JavaObject) return es; // PointsTo() calls n->uncast() which can return a new ideal node. if (n->uncast()->_idx >= nodes_size()) return PointsToNode::UnknownEscape; PointsToNode::EscapeState orig_es = es; // compute max escape state of anything this node could point to VectorSet ptset(Thread::current()->resource_area()); PointsTo(ptset, n); for(VectorSetI i(&ptset); i.test() && es != PointsToNode::GlobalEscape; ++i) { uint pt = i.elem; PointsToNode::EscapeState pes = ptnode_adr(pt)->escape_state(); if (pes > es) es = pes; } if (orig_es != es) { // cache the computed escape state assert(es != PointsToNode::UnknownEscape, "should have computed an escape state"); ptnode_adr(idx)->set_escape_state(es); } // orig_es could be PointsToNode::UnknownEscape return es; } void ConnectionGraph::PointsTo(VectorSet &ptset, Node * n) { VectorSet visited(Thread::current()->resource_area()); GrowableArray worklist; #ifdef ASSERT Node *orig_n = n; #endif n = n->uncast(); PointsToNode* npt = ptnode_adr(n->_idx); // If we have a JavaObject, return just that object if (npt->node_type() == PointsToNode::JavaObject) { ptset.set(n->_idx); return; } #ifdef ASSERT if (npt->_node == NULL) { if (orig_n != n) orig_n->dump(); n->dump(); assert(npt->_node != NULL, "unregistered node"); } #endif worklist.push(n->_idx); while(worklist.length() > 0) { int ni = worklist.pop(); if (visited.test_set(ni)) continue; PointsToNode* pn = ptnode_adr(ni); // ensure that all inputs of a Phi have been processed assert(!_collecting || !pn->_node->is_Phi() || _processed.test(ni),""); int edges_processed = 0; uint e_cnt = pn->edge_count(); for (uint e = 0; e < e_cnt; e++) { uint etgt = pn->edge_target(e); PointsToNode::EdgeType et = pn->edge_type(e); if (et == PointsToNode::PointsToEdge) { ptset.set(etgt); edges_processed++; } else if (et == PointsToNode::DeferredEdge) { worklist.push(etgt); edges_processed++; } else { assert(false,"neither PointsToEdge or DeferredEdge"); } } if (edges_processed == 0) { // no deferred or pointsto edges found. Assume the value was set // outside this method. Add the phantom object to the pointsto set. ptset.set(_phantom_object); } } } void ConnectionGraph::remove_deferred(uint ni, GrowableArray* deferred_edges, VectorSet* visited) { // This method is most expensive during ConnectionGraph construction. // Reuse vectorSet and an additional growable array for deferred edges. deferred_edges->clear(); visited->Clear(); visited->set(ni); PointsToNode *ptn = ptnode_adr(ni); // Mark current edges as visited and move deferred edges to separate array. for (uint i = 0; i < ptn->edge_count(); ) { uint t = ptn->edge_target(i); #ifdef ASSERT assert(!visited->test_set(t), "expecting no duplications"); #else visited->set(t); #endif if (ptn->edge_type(i) == PointsToNode::DeferredEdge) { ptn->remove_edge(t, PointsToNode::DeferredEdge); deferred_edges->append(t); } else { i++; } } for (int next = 0; next < deferred_edges->length(); ++next) { uint t = deferred_edges->at(next); PointsToNode *ptt = ptnode_adr(t); uint e_cnt = ptt->edge_count(); for (uint e = 0; e < e_cnt; e++) { uint etgt = ptt->edge_target(e); if (visited->test_set(etgt)) continue; PointsToNode::EdgeType et = ptt->edge_type(e); if (et == PointsToNode::PointsToEdge) { add_pointsto_edge(ni, etgt); if(etgt == _phantom_object) { // Special case - field set outside (globally escaping). ptn->set_escape_state(PointsToNode::GlobalEscape); } } else if (et == PointsToNode::DeferredEdge) { deferred_edges->append(etgt); } else { assert(false,"invalid connection graph"); } } } } // Add an edge to node given by "to_i" from any field of adr_i whose offset // matches "offset" A deferred edge is added if to_i is a LocalVar, and // a pointsto edge is added if it is a JavaObject void ConnectionGraph::add_edge_from_fields(uint adr_i, uint to_i, int offs) { PointsToNode* an = ptnode_adr(adr_i); PointsToNode* to = ptnode_adr(to_i); bool deferred = (to->node_type() == PointsToNode::LocalVar); for (uint fe = 0; fe < an->edge_count(); fe++) { assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge"); int fi = an->edge_target(fe); PointsToNode* pf = ptnode_adr(fi); int po = pf->offset(); if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) { if (deferred) add_deferred_edge(fi, to_i); else add_pointsto_edge(fi, to_i); } } } // Add a deferred edge from node given by "from_i" to any field of adr_i // whose offset matches "offset". void ConnectionGraph::add_deferred_edge_to_fields(uint from_i, uint adr_i, int offs) { PointsToNode* an = ptnode_adr(adr_i); for (uint fe = 0; fe < an->edge_count(); fe++) { assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge"); int fi = an->edge_target(fe); PointsToNode* pf = ptnode_adr(fi); int po = pf->offset(); if (pf->edge_count() == 0) { // we have not seen any stores to this field, assume it was set outside this method add_pointsto_edge(fi, _phantom_object); } if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) { add_deferred_edge(from_i, fi); } } } // Helper functions static Node* get_addp_base(Node *addp) { assert(addp->is_AddP(), "must be AddP"); // // AddP cases for Base and Address inputs: // case #1. Direct object's field reference: // Allocate // | // Proj #5 ( oop result ) // | // CheckCastPP (cast to instance type) // | | // AddP ( base == address ) // // case #2. Indirect object's field reference: // Phi // | // CastPP (cast to instance type) // | | // AddP ( base == address ) // // case #3. Raw object's field reference for Initialize node: // Allocate // | // Proj #5 ( oop result ) // top | // \ | // AddP ( base == top ) // // case #4. Array's element reference: // {CheckCastPP | CastPP} // | | | // | AddP ( array's element offset ) // | | // AddP ( array's offset ) // // case #5. Raw object's field reference for arraycopy stub call: // The inline_native_clone() case when the arraycopy stub is called // after the allocation before Initialize and CheckCastPP nodes. // Allocate // | // Proj #5 ( oop result ) // | | // AddP ( base == address ) // // case #6. Constant Pool, ThreadLocal, CastX2P or // Raw object's field reference: // {ConP, ThreadLocal, CastX2P, raw Load} // top | // \ | // AddP ( base == top ) // // case #7. Klass's field reference. // LoadKlass // | | // AddP ( base == address ) // // case #8. narrow Klass's field reference. // LoadNKlass // | // DecodeN // | | // AddP ( base == address ) // Node *base = addp->in(AddPNode::Base)->uncast(); if (base->is_top()) { // The AddP case #3 and #6. base = addp->in(AddPNode::Address)->uncast(); while (base->is_AddP()) { // Case #6 (unsafe access) may have several chained AddP nodes. assert(base->in(AddPNode::Base)->is_top(), "expected unsafe access address only"); base = base->in(AddPNode::Address)->uncast(); } assert(base->Opcode() == Op_ConP || base->Opcode() == Op_ThreadLocal || base->Opcode() == Op_CastX2P || base->is_DecodeN() || (base->is_Mem() && base->bottom_type() == TypeRawPtr::NOTNULL) || (base->is_Proj() && base->in(0)->is_Allocate()), "sanity"); } return base; } static Node* find_second_addp(Node* addp, Node* n) { assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes"); Node* addp2 = addp->raw_out(0); if (addp->outcnt() == 1 && addp2->is_AddP() && addp2->in(AddPNode::Base) == n && addp2->in(AddPNode::Address) == addp) { assert(addp->in(AddPNode::Base) == n, "expecting the same base"); // // Find array's offset to push it on worklist first and // as result process an array's element offset first (pushed second) // to avoid CastPP for the array's offset. // Otherwise the inserted CastPP (LocalVar) will point to what // the AddP (Field) points to. Which would be wrong since // the algorithm expects the CastPP has the same point as // as AddP's base CheckCastPP (LocalVar). // // ArrayAllocation // | // CheckCastPP // | // memProj (from ArrayAllocation CheckCastPP) // | || // | || Int (element index) // | || | ConI (log(element size)) // | || | / // | || LShift // | || / // | AddP (array's element offset) // | | // | | ConI (array's offset: #12(32-bits) or #24(64-bits)) // | / / // AddP (array's offset) // | // Load/Store (memory operation on array's element) // return addp2; } return NULL; } // // Adjust the type and inputs of an AddP which computes the // address of a field of an instance // bool ConnectionGraph::split_AddP(Node *addp, Node *base, PhaseGVN *igvn) { const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr(); assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr"); const TypeOopPtr *t = igvn->type(addp)->isa_oopptr(); if (t == NULL) { // We are computing a raw address for a store captured by an Initialize // compute an appropriate address type (cases #3 and #5). assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer"); assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation"); intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot); assert(offs != Type::OffsetBot, "offset must be a constant"); t = base_t->add_offset(offs)->is_oopptr(); } int inst_id = base_t->instance_id(); assert(!t->is_known_instance() || t->instance_id() == inst_id, "old type must be non-instance or match new type"); // The type 't' could be subclass of 'base_t'. // As result t->offset() could be large then base_t's size and it will // cause the failure in add_offset() with narrow oops since TypeOopPtr() // constructor verifies correctness of the offset. // // It could happened on subclass's branch (from the type profiling // inlining) which was not eliminated during parsing since the exactness // of the allocation type was not propagated to the subclass type check. // // Or the type 't' could be not related to 'base_t' at all. // It could happened when CHA type is different from MDO type on a dead path // (for example, from instanceof check) which is not collapsed during parsing. // // Do nothing for such AddP node and don't process its users since // this code branch will go away. // if (!t->is_known_instance() && !base_t->klass()->is_subtype_of(t->klass())) { return false; // bail out } const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr(); // Do NOT remove the next line: ensure a new alias index is allocated // for the instance type. Note: C++ will not remove it since the call // has side effect. int alias_idx = _compile->get_alias_index(tinst); igvn->set_type(addp, tinst); // record the allocation in the node map assert(ptnode_adr(addp->_idx)->_node != NULL, "should be registered"); set_map(addp->_idx, get_map(base->_idx)); // Set addp's Base and Address to 'base'. Node *abase = addp->in(AddPNode::Base); Node *adr = addp->in(AddPNode::Address); if (adr->is_Proj() && adr->in(0)->is_Allocate() && adr->in(0)->_idx == (uint)inst_id) { // Skip AddP cases #3 and #5. } else { assert(!abase->is_top(), "sanity"); // AddP case #3 if (abase != base) { igvn->hash_delete(addp); addp->set_req(AddPNode::Base, base); if (abase == adr) { addp->set_req(AddPNode::Address, base); } else { // AddP case #4 (adr is array's element offset AddP node) #ifdef ASSERT const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr(); assert(adr->is_AddP() && atype != NULL && atype->instance_id() == inst_id, "array's element offset should be processed first"); #endif } igvn->hash_insert(addp); } } // Put on IGVN worklist since at least addp's type was changed above. record_for_optimizer(addp); return true; } // // Create a new version of orig_phi if necessary. Returns either the newly // created phi or an existing phi. Sets create_new to indicate wheter a new // phi was created. Cache the last newly created phi in the node map. // PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray &orig_phi_worklist, PhaseGVN *igvn, bool &new_created) { Compile *C = _compile; new_created = false; int phi_alias_idx = C->get_alias_index(orig_phi->adr_type()); // nothing to do if orig_phi is bottom memory or matches alias_idx if (phi_alias_idx == alias_idx) { return orig_phi; } // Have we recently created a Phi for this alias index? PhiNode *result = get_map_phi(orig_phi->_idx); if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) { return result; } // Previous check may fail when the same wide memory Phi was split into Phis // for different memory slices. Search all Phis for this region. if (result != NULL) { Node* region = orig_phi->in(0); for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) { Node* phi = region->fast_out(i); if (phi->is_Phi() && C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) { assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice"); return phi->as_Phi(); } } } if ((int)C->unique() + 2*NodeLimitFudgeFactor > MaxNodeLimit) { if (C->do_escape_analysis() == true && !C->failing()) { // Retry compilation without escape analysis. // If this is the first failure, the sentinel string will "stick" // to the Compile object, and the C2Compiler will see it and retry. C->record_failure(C2Compiler::retry_no_escape_analysis()); } return NULL; } orig_phi_worklist.append_if_missing(orig_phi); const TypePtr *atype = C->get_adr_type(alias_idx); result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype); C->copy_node_notes_to(result, orig_phi); igvn->set_type(result, result->bottom_type()); record_for_optimizer(result); debug_only(Node* pn = ptnode_adr(orig_phi->_idx)->_node;) assert(pn == NULL || pn == orig_phi, "wrong node"); set_map(orig_phi->_idx, result); ptnode_adr(orig_phi->_idx)->_node = orig_phi; new_created = true; return result; } // // Return a new version of Memory Phi "orig_phi" with the inputs having the // specified alias index. // PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray &orig_phi_worklist, PhaseGVN *igvn) { assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory"); Compile *C = _compile; bool new_phi_created; PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, igvn, new_phi_created); if (!new_phi_created) { return result; } GrowableArray phi_list; GrowableArray cur_input; PhiNode *phi = orig_phi; uint idx = 1; bool finished = false; while(!finished) { while (idx < phi->req()) { Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist, igvn); if (mem != NULL && mem->is_Phi()) { PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, igvn, new_phi_created); if (new_phi_created) { // found an phi for which we created a new split, push current one on worklist and begin // processing new one phi_list.push(phi); cur_input.push(idx); phi = mem->as_Phi(); result = newphi; idx = 1; continue; } else { mem = newphi; } } if (C->failing()) { return NULL; } result->set_req(idx++, mem); } #ifdef ASSERT // verify that the new Phi has an input for each input of the original assert( phi->req() == result->req(), "must have same number of inputs."); assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match"); #endif // Check if all new phi's inputs have specified alias index. // Otherwise use old phi. for (uint i = 1; i < phi->req(); i++) { Node* in = result->in(i); assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond."); } // we have finished processing a Phi, see if there are any more to do finished = (phi_list.length() == 0 ); if (!finished) { phi = phi_list.pop(); idx = cur_input.pop(); PhiNode *prev_result = get_map_phi(phi->_idx); prev_result->set_req(idx++, result); result = prev_result; } } return result; } // // The next methods are derived from methods in MemNode. // static Node *step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) { Node *mem = mmem; // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally // means an array I have not precisely typed yet. Do not do any // alias stuff with it any time soon. if( toop->base() != Type::AnyPtr && !(toop->klass() != NULL && toop->klass()->is_java_lang_Object() && toop->offset() == Type::OffsetBot) ) { mem = mmem->memory_at(alias_idx); // Update input if it is progress over what we have now } return mem; } // // Move memory users to their memory slices. // void ConnectionGraph::move_inst_mem(Node* n, GrowableArray &orig_phis, PhaseGVN *igvn) { Compile* C = _compile; const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr(); assert(tp != NULL, "ptr type"); int alias_idx = C->get_alias_index(tp); int general_idx = C->get_general_index(alias_idx); // Move users first for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { Node* use = n->fast_out(i); if (use->is_MergeMem()) { MergeMemNode* mmem = use->as_MergeMem(); assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice"); if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) { continue; // Nothing to do } // Replace previous general reference to mem node. uint orig_uniq = C->unique(); Node* m = find_inst_mem(n, general_idx, orig_phis, igvn); assert(orig_uniq == C->unique(), "no new nodes"); mmem->set_memory_at(general_idx, m); --imax; --i; } else if (use->is_MemBar()) { assert(!use->is_Initialize(), "initializing stores should not be moved"); if (use->req() > MemBarNode::Precedent && use->in(MemBarNode::Precedent) == n) { // Don't move related membars. record_for_optimizer(use); continue; } tp = use->as_MemBar()->adr_type()->isa_ptr(); if (tp != NULL && C->get_alias_index(tp) == alias_idx || alias_idx == general_idx) { continue; // Nothing to do } // Move to general memory slice. uint orig_uniq = C->unique(); Node* m = find_inst_mem(n, general_idx, orig_phis, igvn); assert(orig_uniq == C->unique(), "no new nodes"); igvn->hash_delete(use); imax -= use->replace_edge(n, m); igvn->hash_insert(use); record_for_optimizer(use); --i; #ifdef ASSERT } else if (use->is_Mem()) { if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) { // Don't move related cardmark. continue; } // Memory nodes should have new memory input. tp = igvn->type(use->in(MemNode::Address))->isa_ptr(); assert(tp != NULL, "ptr type"); int idx = C->get_alias_index(tp); assert(get_map(use->_idx) != NULL || idx == alias_idx, "Following memory nodes should have new memory input or be on the same memory slice"); } else if (use->is_Phi()) { // Phi nodes should be split and moved already. tp = use->as_Phi()->adr_type()->isa_ptr(); assert(tp != NULL, "ptr type"); int idx = C->get_alias_index(tp); assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice"); } else { use->dump(); assert(false, "should not be here"); #endif } } } // // Search memory chain of "mem" to find a MemNode whose address // is the specified alias index. // Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray &orig_phis, PhaseGVN *phase) { if (orig_mem == NULL) return orig_mem; Compile* C = phase->C; const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr(); bool is_instance = (toop != NULL) && toop->is_known_instance(); Node *start_mem = C->start()->proj_out(TypeFunc::Memory); Node *prev = NULL; Node *result = orig_mem; while (prev != result) { prev = result; if (result == start_mem) break; // hit one of our sentinels if (result->is_Mem()) { const Type *at = phase->type(result->in(MemNode::Address)); if (at != Type::TOP) { assert (at->isa_ptr() != NULL, "pointer type required."); int idx = C->get_alias_index(at->is_ptr()); if (idx == alias_idx) break; } result = result->in(MemNode::Memory); } if (!is_instance) continue; // don't search further for non-instance types // skip over a call which does not affect this memory slice if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) { Node *proj_in = result->in(0); if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) { break; // hit one of our sentinels } else if (proj_in->is_Call()) { CallNode *call = proj_in->as_Call(); if (!call->may_modify(toop, phase)) { result = call->in(TypeFunc::Memory); } } else if (proj_in->is_Initialize()) { AllocateNode* alloc = proj_in->as_Initialize()->allocation(); // Stop if this is the initialization for the object instance which // which contains this memory slice, otherwise skip over it. if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) { result = proj_in->in(TypeFunc::Memory); } } else if (proj_in->is_MemBar()) { result = proj_in->in(TypeFunc::Memory); } } else if (result->is_MergeMem()) { MergeMemNode *mmem = result->as_MergeMem(); result = step_through_mergemem(mmem, alias_idx, toop); if (result == mmem->base_memory()) { // Didn't find instance memory, search through general slice recursively. result = mmem->memory_at(C->get_general_index(alias_idx)); result = find_inst_mem(result, alias_idx, orig_phis, phase); if (C->failing()) { return NULL; } mmem->set_memory_at(alias_idx, result); } } else if (result->is_Phi() && C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) { Node *un = result->as_Phi()->unique_input(phase); if (un != NULL) { orig_phis.append_if_missing(result->as_Phi()); result = un; } else { break; } } else if (result->is_ClearArray()) { if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), phase)) { // Can not bypass initialization of the instance // we are looking for. break; } // Otherwise skip it (the call updated 'result' value). } else if (result->Opcode() == Op_SCMemProj) { assert(result->in(0)->is_LoadStore(), "sanity"); const Type *at = phase->type(result->in(0)->in(MemNode::Address)); if (at != Type::TOP) { assert (at->isa_ptr() != NULL, "pointer type required."); int idx = C->get_alias_index(at->is_ptr()); assert(idx != alias_idx, "Object is not scalar replaceable if a LoadStore node access its field"); break; } result = result->in(0)->in(MemNode::Memory); } } if (result->is_Phi()) { PhiNode *mphi = result->as_Phi(); assert(mphi->bottom_type() == Type::MEMORY, "memory phi required"); const TypePtr *t = mphi->adr_type(); if (C->get_alias_index(t) != alias_idx) { // Create a new Phi with the specified alias index type. result = split_memory_phi(mphi, alias_idx, orig_phis, phase); } else if (!is_instance) { // Push all non-instance Phis on the orig_phis worklist to update inputs // during Phase 4 if needed. orig_phis.append_if_missing(mphi); } } // the result is either MemNode, PhiNode, InitializeNode. return result; } // // Convert the types of unescaped object to instance types where possible, // propagate the new type information through the graph, and update memory // edges and MergeMem inputs to reflect the new type. // // We start with allocations (and calls which may be allocations) on alloc_worklist. // The processing is done in 4 phases: // // Phase 1: Process possible allocations from alloc_worklist. Create instance // types for the CheckCastPP for allocations where possible. // Propagate the the new types through users as follows: // casts and Phi: push users on alloc_worklist // AddP: cast Base and Address inputs to the instance type // push any AddP users on alloc_worklist and push any memnode // users onto memnode_worklist. // Phase 2: Process MemNode's from memnode_worklist. compute new address type and // search the Memory chain for a store with the appropriate type // address type. If a Phi is found, create a new version with // the appropriate memory slices from each of the Phi inputs. // For stores, process the users as follows: // MemNode: push on memnode_worklist // MergeMem: push on mergemem_worklist // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice // moving the first node encountered of each instance type to the // the input corresponding to its alias index. // appropriate memory slice. // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes. // // In the following example, the CheckCastPP nodes are the cast of allocation // results and the allocation of node 29 is unescaped and eligible to be an // instance type. // // We start with: // // 7 Parm #memory // 10 ConI "12" // 19 CheckCastPP "Foo" // 20 AddP _ 19 19 10 Foo+12 alias_index=4 // 29 CheckCastPP "Foo" // 30 AddP _ 29 29 10 Foo+12 alias_index=4 // // 40 StoreP 25 7 20 ... alias_index=4 // 50 StoreP 35 40 30 ... alias_index=4 // 60 StoreP 45 50 20 ... alias_index=4 // 70 LoadP _ 60 30 ... alias_index=4 // 80 Phi 75 50 60 Memory alias_index=4 // 90 LoadP _ 80 30 ... alias_index=4 // 100 LoadP _ 80 20 ... alias_index=4 // // // Phase 1 creates an instance type for node 29 assigning it an instance id of 24 // and creating a new alias index for node 30. This gives: // // 7 Parm #memory // 10 ConI "12" // 19 CheckCastPP "Foo" // 20 AddP _ 19 19 10 Foo+12 alias_index=4 // 29 CheckCastPP "Foo" iid=24 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 // // 40 StoreP 25 7 20 ... alias_index=4 // 50 StoreP 35 40 30 ... alias_index=6 // 60 StoreP 45 50 20 ... alias_index=4 // 70 LoadP _ 60 30 ... alias_index=6 // 80 Phi 75 50 60 Memory alias_index=4 // 90 LoadP _ 80 30 ... alias_index=6 // 100 LoadP _ 80 20 ... alias_index=4 // // In phase 2, new memory inputs are computed for the loads and stores, // And a new version of the phi is created. In phase 4, the inputs to // node 80 are updated and then the memory nodes are updated with the // values computed in phase 2. This results in: // // 7 Parm #memory // 10 ConI "12" // 19 CheckCastPP "Foo" // 20 AddP _ 19 19 10 Foo+12 alias_index=4 // 29 CheckCastPP "Foo" iid=24 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24 // // 40 StoreP 25 7 20 ... alias_index=4 // 50 StoreP 35 7 30 ... alias_index=6 // 60 StoreP 45 40 20 ... alias_index=4 // 70 LoadP _ 50 30 ... alias_index=6 // 80 Phi 75 40 60 Memory alias_index=4 // 120 Phi 75 50 50 Memory alias_index=6 // 90 LoadP _ 120 30 ... alias_index=6 // 100 LoadP _ 80 20 ... alias_index=4 // void ConnectionGraph::split_unique_types(GrowableArray &alloc_worklist) { GrowableArray memnode_worklist; GrowableArray orig_phis; PhaseGVN *igvn = _igvn; uint new_index_start = (uint) _compile->num_alias_types(); Arena* arena = Thread::current()->resource_area(); VectorSet visited(arena); VectorSet ptset(arena); // Phase 1: Process possible allocations from alloc_worklist. // Create instance types for the CheckCastPP for allocations where possible. // // (Note: don't forget to change the order of the second AddP node on // the alloc_worklist if the order of the worklist processing is changed, // see the comment in find_second_addp().) // while (alloc_worklist.length() != 0) { Node *n = alloc_worklist.pop(); uint ni = n->_idx; const TypeOopPtr* tinst = NULL; if (n->is_Call()) { CallNode *alloc = n->as_Call(); // copy escape information to call node PointsToNode* ptn = ptnode_adr(alloc->_idx); PointsToNode::EscapeState es = escape_state(alloc); // We have an allocation or call which returns a Java object, // see if it is unescaped. if (es != PointsToNode::NoEscape || !ptn->_scalar_replaceable) continue; // Find CheckCastPP for the allocate or for the return value of a call n = alloc->result_cast(); if (n == NULL) { // No uses except Initialize node if (alloc->is_Allocate()) { // Set the scalar_replaceable flag for allocation // so it could be eliminated if it has no uses. alloc->as_Allocate()->_is_scalar_replaceable = true; } continue; } if (!n->is_CheckCastPP()) { // not unique CheckCastPP. assert(!alloc->is_Allocate(), "allocation should have unique type"); continue; } // The inline code for Object.clone() casts the allocation result to // java.lang.Object and then to the actual type of the allocated // object. Detect this case and use the second cast. // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when // the allocation result is cast to java.lang.Object and then // to the actual Array type. if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL && (alloc->is_AllocateArray() || igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) { Node *cast2 = NULL; for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { Node *use = n->fast_out(i); if (use->is_CheckCastPP()) { cast2 = use; break; } } if (cast2 != NULL) { n = cast2; } else { // Non-scalar replaceable if the allocation type is unknown statically // (reflection allocation), the object can't be restored during // deoptimization without precise type. continue; } } if (alloc->is_Allocate()) { // Set the scalar_replaceable flag for allocation // so it could be eliminated. alloc->as_Allocate()->_is_scalar_replaceable = true; } set_escape_state(n->_idx, es); // in order for an object to be scalar-replaceable, it must be: // - a direct allocation (not a call returning an object) // - non-escaping // - eligible to be a unique type // - not determined to be ineligible by escape analysis assert(ptnode_adr(alloc->_idx)->_node != NULL && ptnode_adr(n->_idx)->_node != NULL, "should be registered"); set_map(alloc->_idx, n); set_map(n->_idx, alloc); const TypeOopPtr *t = igvn->type(n)->isa_oopptr(); if (t == NULL) continue; // not a TypeInstPtr tinst = t->cast_to_exactness(true)->is_oopptr()->cast_to_instance_id(ni); igvn->hash_delete(n); igvn->set_type(n, tinst); n->raise_bottom_type(tinst); igvn->hash_insert(n); record_for_optimizer(n); if (alloc->is_Allocate() && ptn->_scalar_replaceable && (t->isa_instptr() || t->isa_aryptr())) { // First, put on the worklist all Field edges from Connection Graph // which is more accurate then putting immediate users from Ideal Graph. for (uint e = 0; e < ptn->edge_count(); e++) { Node *use = ptnode_adr(ptn->edge_target(e))->_node; assert(ptn->edge_type(e) == PointsToNode::FieldEdge && use->is_AddP(), "only AddP nodes are Field edges in CG"); if (use->outcnt() > 0) { // Don't process dead nodes Node* addp2 = find_second_addp(use, use->in(AddPNode::Base)); if (addp2 != NULL) { assert(alloc->is_AllocateArray(),"array allocation was expected"); alloc_worklist.append_if_missing(addp2); } alloc_worklist.append_if_missing(use); } } // An allocation may have an Initialize which has raw stores. Scan // the users of the raw allocation result and push AddP users // on alloc_worklist. Node *raw_result = alloc->proj_out(TypeFunc::Parms); assert (raw_result != NULL, "must have an allocation result"); for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) { Node *use = raw_result->fast_out(i); if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes Node* addp2 = find_second_addp(use, raw_result); if (addp2 != NULL) { assert(alloc->is_AllocateArray(),"array allocation was expected"); alloc_worklist.append_if_missing(addp2); } alloc_worklist.append_if_missing(use); } else if (use->is_MemBar()) { memnode_worklist.append_if_missing(use); } } } } else if (n->is_AddP()) { ptset.Clear(); PointsTo(ptset, get_addp_base(n)); assert(ptset.Size() == 1, "AddP address is unique"); uint elem = ptset.getelem(); // Allocation node's index if (elem == _phantom_object) { assert(false, "escaped allocation"); continue; // Assume the value was set outside this method. } Node *base = get_map(elem); // CheckCastPP node if (!split_AddP(n, base, igvn)) continue; // wrong type from dead path tinst = igvn->type(base)->isa_oopptr(); } else if (n->is_Phi() || n->is_CheckCastPP() || n->is_EncodeP() || n->is_DecodeN() || (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) { if (visited.test_set(n->_idx)) { assert(n->is_Phi(), "loops only through Phi's"); continue; // already processed } ptset.Clear(); PointsTo(ptset, n); if (ptset.Size() == 1) { uint elem = ptset.getelem(); // Allocation node's index if (elem == _phantom_object) { assert(false, "escaped allocation"); continue; // Assume the value was set outside this method. } Node *val = get_map(elem); // CheckCastPP node TypeNode *tn = n->as_Type(); tinst = igvn->type(val)->isa_oopptr(); assert(tinst != NULL && tinst->is_known_instance() && (uint)tinst->instance_id() == elem , "instance type expected."); const Type *tn_type = igvn->type(tn); const TypeOopPtr *tn_t; if (tn_type->isa_narrowoop()) { tn_t = tn_type->make_ptr()->isa_oopptr(); } else { tn_t = tn_type->isa_oopptr(); } if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) { if (tn_type->isa_narrowoop()) { tn_type = tinst->make_narrowoop(); } else { tn_type = tinst; } igvn->hash_delete(tn); igvn->set_type(tn, tn_type); tn->set_type(tn_type); igvn->hash_insert(tn); record_for_optimizer(n); } else { assert(tn_type == TypePtr::NULL_PTR || tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()), "unexpected type"); continue; // Skip dead path with different type } } } else { debug_only(n->dump();) assert(false, "EA: unexpected node"); continue; } // push allocation's users on appropriate worklist for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { Node *use = n->fast_out(i); if(use->is_Mem() && use->in(MemNode::Address) == n) { // Load/store to instance's field memnode_worklist.append_if_missing(use); } else if (use->is_MemBar()) { memnode_worklist.append_if_missing(use); } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes Node* addp2 = find_second_addp(use, n); if (addp2 != NULL) { alloc_worklist.append_if_missing(addp2); } alloc_worklist.append_if_missing(use); } else if (use->is_Phi() || use->is_CheckCastPP() || use->is_EncodeP() || use->is_DecodeN() || (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) { alloc_worklist.append_if_missing(use); #ifdef ASSERT } else if (use->is_Mem()) { assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path"); } else if (use->is_MergeMem()) { assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); } else if (use->is_SafePoint()) { // Look for MergeMem nodes for calls which reference unique allocation // (through CheckCastPP nodes) even for debug info. Node* m = use->in(TypeFunc::Memory); if (m->is_MergeMem()) { assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist"); } } else { uint op = use->Opcode(); if (!(op == Op_CmpP || op == Op_Conv2B || op == Op_CastP2X || op == Op_StoreCM || op == Op_FastLock || op == Op_AryEq || op == Op_StrComp || op == Op_StrEquals || op == Op_StrIndexOf)) { n->dump(); use->dump(); assert(false, "EA: missing allocation reference path"); } #endif } } } // New alias types were created in split_AddP(). uint new_index_end = (uint) _compile->num_alias_types(); // Phase 2: Process MemNode's from memnode_worklist. compute new address type and // compute new values for Memory inputs (the Memory inputs are not // actually updated until phase 4.) if (memnode_worklist.length() == 0) return; // nothing to do while (memnode_worklist.length() != 0) { Node *n = memnode_worklist.pop(); if (visited.test_set(n->_idx)) continue; if (n->is_Phi() || n->is_ClearArray()) { // we don't need to do anything, but the users must be pushed } else if (n->is_MemBar()) { // Initialize, MemBar nodes // we don't need to do anything, but the users must be pushed n = n->as_MemBar()->proj_out(TypeFunc::Memory); if (n == NULL) continue; } else { assert(n->is_Mem(), "memory node required."); Node *addr = n->in(MemNode::Address); const Type *addr_t = igvn->type(addr); if (addr_t == Type::TOP) continue; assert (addr_t->isa_ptr() != NULL, "pointer type required."); int alias_idx = _compile->get_alias_index(addr_t->is_ptr()); assert ((uint)alias_idx < new_index_end, "wrong alias index"); Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis, igvn); if (_compile->failing()) { return; } if (mem != n->in(MemNode::Memory)) { // We delay the memory edge update since we need old one in // MergeMem code below when instances memory slices are separated. debug_only(Node* pn = ptnode_adr(n->_idx)->_node;) assert(pn == NULL || pn == n, "wrong node"); set_map(n->_idx, mem); ptnode_adr(n->_idx)->_node = n; } if (n->is_Load()) { continue; // don't push users } else if (n->is_LoadStore()) { // get the memory projection for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { Node *use = n->fast_out(i); if (use->Opcode() == Op_SCMemProj) { n = use; break; } } assert(n->Opcode() == Op_SCMemProj, "memory projection required"); } } // push user on appropriate worklist for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { Node *use = n->fast_out(i); if (use->is_Phi() || use->is_ClearArray()) { memnode_worklist.append_if_missing(use); } else if(use->is_Mem() && use->in(MemNode::Memory) == n) { if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores continue; memnode_worklist.append_if_missing(use); } else if (use->is_MemBar()) { memnode_worklist.append_if_missing(use); #ifdef ASSERT } else if(use->is_Mem()) { assert(use->in(MemNode::Memory) != n, "EA: missing memory path"); } else if (use->is_MergeMem()) { assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist"); } else { uint op = use->Opcode(); if (!(op == Op_StoreCM || (op == Op_CallLeaf && use->as_CallLeaf()->_name != NULL && strcmp(use->as_CallLeaf()->_name, "g1_wb_pre") == 0) || op == Op_AryEq || op == Op_StrComp || op == Op_StrEquals || op == Op_StrIndexOf)) { n->dump(); use->dump(); assert(false, "EA: missing memory path"); } #endif } } } // Phase 3: Process MergeMem nodes from mergemem_worklist. // Walk each memory slice moving the first node encountered of each // instance type to the the input corresponding to its alias index. uint length = _mergemem_worklist.length(); for( uint next = 0; next < length; ++next ) { MergeMemNode* nmm = _mergemem_worklist.at(next); assert(!visited.test_set(nmm->_idx), "should not be visited before"); // Note: we don't want to use MergeMemStream here because we only want to // scan inputs which exist at the start, not ones we add during processing. // Note 2: MergeMem may already contains instance memory slices added // during find_inst_mem() call when memory nodes were processed above. igvn->hash_delete(nmm); uint nslices = nmm->req(); for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) { Node* mem = nmm->in(i); Node* cur = NULL; if (mem == NULL || mem->is_top()) continue; // First, update mergemem by moving memory nodes to corresponding slices // if their type became more precise since this mergemem was created. while (mem->is_Mem()) { const Type *at = igvn->type(mem->in(MemNode::Address)); if (at != Type::TOP) { assert (at->isa_ptr() != NULL, "pointer type required."); uint idx = (uint)_compile->get_alias_index(at->is_ptr()); if (idx == i) { if (cur == NULL) cur = mem; } else { if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) { nmm->set_memory_at(idx, mem); } } } mem = mem->in(MemNode::Memory); } nmm->set_memory_at(i, (cur != NULL) ? cur : mem); // Find any instance of the current type if we haven't encountered // already a memory slice of the instance along the memory chain. for (uint ni = new_index_start; ni < new_index_end; ni++) { if((uint)_compile->get_general_index(ni) == i) { Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni); if (nmm->is_empty_memory(m)) { Node* result = find_inst_mem(mem, ni, orig_phis, igvn); if (_compile->failing()) { return; } nmm->set_memory_at(ni, result); } } } } // Find the rest of instances values for (uint ni = new_index_start; ni < new_index_end; ni++) { const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr(); Node* result = step_through_mergemem(nmm, ni, tinst); if (result == nmm->base_memory()) { // Didn't find instance memory, search through general slice recursively. result = nmm->memory_at(_compile->get_general_index(ni)); result = find_inst_mem(result, ni, orig_phis, igvn); if (_compile->failing()) { return; } nmm->set_memory_at(ni, result); } } igvn->hash_insert(nmm); record_for_optimizer(nmm); } // Phase 4: Update the inputs of non-instance memory Phis and // the Memory input of memnodes // First update the inputs of any non-instance Phi's from // which we split out an instance Phi. Note we don't have // to recursively process Phi's encounted on the input memory // chains as is done in split_memory_phi() since they will // also be processed here. for (int j = 0; j < orig_phis.length(); j++) { PhiNode *phi = orig_phis.at(j); int alias_idx = _compile->get_alias_index(phi->adr_type()); igvn->hash_delete(phi); for (uint i = 1; i < phi->req(); i++) { Node *mem = phi->in(i); Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis, igvn); if (_compile->failing()) { return; } if (mem != new_mem) { phi->set_req(i, new_mem); } } igvn->hash_insert(phi); record_for_optimizer(phi); } // Update the memory inputs of MemNodes with the value we computed // in Phase 2 and move stores memory users to corresponding memory slices. #ifdef ASSERT visited.Clear(); Node_Stack old_mems(arena, _compile->unique() >> 2); #endif for (uint i = 0; i < nodes_size(); i++) { Node *nmem = get_map(i); if (nmem != NULL) { Node *n = ptnode_adr(i)->_node; assert(n != NULL, "sanity"); if (n->is_Mem()) { #ifdef ASSERT Node* old_mem = n->in(MemNode::Memory); if (!visited.test_set(old_mem->_idx)) { old_mems.push(old_mem, old_mem->outcnt()); } #endif assert(n->in(MemNode::Memory) != nmem, "sanity"); if (!n->is_Load()) { // Move memory users of a store first. move_inst_mem(n, orig_phis, igvn); } // Now update memory input igvn->hash_delete(n); n->set_req(MemNode::Memory, nmem); igvn->hash_insert(n); record_for_optimizer(n); } else { assert(n->is_Allocate() || n->is_CheckCastPP() || n->is_AddP() || n->is_Phi(), "unknown node used for set_map()"); } } } #ifdef ASSERT // Verify that memory was split correctly while (old_mems.is_nonempty()) { Node* old_mem = old_mems.node(); uint old_cnt = old_mems.index(); old_mems.pop(); assert(old_cnt = old_mem->outcnt(), "old mem could be lost"); } #endif } bool ConnectionGraph::has_candidates(Compile *C) { // EA brings benefits only when the code has allocations and/or locks which // are represented by ideal Macro nodes. int cnt = C->macro_count(); for( int i=0; i < cnt; i++ ) { Node *n = C->macro_node(i); if ( n->is_Allocate() ) return true; if( n->is_Lock() ) { Node* obj = n->as_Lock()->obj_node()->uncast(); if( !(obj->is_Parm() || obj->is_Con()) ) return true; } } return false; } void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) { // Add ConP#NULL and ConN#NULL nodes before ConnectionGraph construction // to create space for them in ConnectionGraph::_nodes[]. Node* oop_null = igvn->zerocon(T_OBJECT); Node* noop_null = igvn->zerocon(T_NARROWOOP); ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn); // Perform escape analysis if (congraph->compute_escape()) { // There are non escaping objects. C->set_congraph(congraph); } // Cleanup. if (oop_null->outcnt() == 0) igvn->hash_delete(oop_null); if (noop_null->outcnt() == 0) igvn->hash_delete(noop_null); } bool ConnectionGraph::compute_escape() { Compile* C = _compile; // 1. Populate Connection Graph (CG) with Ideal nodes. Unique_Node_List worklist_init; worklist_init.map(C->unique(), NULL); // preallocate space // Initialize worklist if (C->root() != NULL) { worklist_init.push(C->root()); } GrowableArray cg_worklist; PhaseGVN* igvn = _igvn; bool has_allocations = false; // Push all useful nodes onto CG list and set their type. for( uint next = 0; next < worklist_init.size(); ++next ) { Node* n = worklist_init.at(next); record_for_escape_analysis(n, igvn); // Only allocations and java static calls results are checked // for an escape status. See process_call_result() below. if (n->is_Allocate() || n->is_CallStaticJava() && ptnode_adr(n->_idx)->node_type() == PointsToNode::JavaObject) { has_allocations = true; } if(n->is_AddP()) { // Collect address nodes which directly reference an allocation. // Use them during stage 3 below to build initial connection graph // field edges. Other field edges could be added after StoreP/LoadP // nodes are processed during stage 4 below. Node* base = get_addp_base(n); if(base->is_Proj() && base->in(0)->is_Allocate()) { cg_worklist.append(n->_idx); } } else if (n->is_MergeMem()) { // Collect all MergeMem nodes to add memory slices for // scalar replaceable objects in split_unique_types(). _mergemem_worklist.append(n->as_MergeMem()); } for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { Node* m = n->fast_out(i); // Get user worklist_init.push(m); } } if (!has_allocations) { _collecting = false; return false; // Nothing to do. } // 2. First pass to create simple CG edges (doesn't require to walk CG). uint delayed_size = _delayed_worklist.size(); for( uint next = 0; next < delayed_size; ++next ) { Node* n = _delayed_worklist.at(next); build_connection_graph(n, igvn); } // 3. Pass to create fields edges (Allocate -F-> AddP). uint cg_length = cg_worklist.length(); for( uint next = 0; next < cg_length; ++next ) { int ni = cg_worklist.at(next); build_connection_graph(ptnode_adr(ni)->_node, igvn); } cg_worklist.clear(); cg_worklist.append(_phantom_object); // 4. Build Connection Graph which need // to walk the connection graph. for (uint ni = 0; ni < nodes_size(); ni++) { PointsToNode* ptn = ptnode_adr(ni); Node *n = ptn->_node; if (n != NULL) { // Call, AddP, LoadP, StoreP build_connection_graph(n, igvn); if (ptn->node_type() != PointsToNode::UnknownType) cg_worklist.append(n->_idx); // Collect CG nodes } } Arena* arena = Thread::current()->resource_area(); VectorSet ptset(arena); GrowableArray deferred_edges; VectorSet visited(arena); // 5. Remove deferred edges from the graph and adjust // escape state of nonescaping objects. cg_length = cg_worklist.length(); for( uint next = 0; next < cg_length; ++next ) { int ni = cg_worklist.at(next); PointsToNode* ptn = ptnode_adr(ni); PointsToNode::NodeType nt = ptn->node_type(); if (nt == PointsToNode::LocalVar || nt == PointsToNode::Field) { remove_deferred(ni, &deferred_edges, &visited); Node *n = ptn->_node; if (n->is_AddP()) { // Search for objects which are not scalar replaceable // and adjust their escape state. verify_escape_state(ni, ptset, igvn); } } } // 6. Propagate escape states. GrowableArray worklist; bool has_non_escaping_obj = false; // push all GlobalEscape nodes on the worklist for( uint next = 0; next < cg_length; ++next ) { int nk = cg_worklist.at(next); if (ptnode_adr(nk)->escape_state() == PointsToNode::GlobalEscape) worklist.push(nk); } // mark all nodes reachable from GlobalEscape nodes while(worklist.length() > 0) { PointsToNode* ptn = ptnode_adr(worklist.pop()); uint e_cnt = ptn->edge_count(); for (uint ei = 0; ei < e_cnt; ei++) { uint npi = ptn->edge_target(ei); PointsToNode *np = ptnode_adr(npi); if (np->escape_state() < PointsToNode::GlobalEscape) { np->set_escape_state(PointsToNode::GlobalEscape); worklist.push(npi); } } } // push all ArgEscape nodes on the worklist for( uint next = 0; next < cg_length; ++next ) { int nk = cg_worklist.at(next); if (ptnode_adr(nk)->escape_state() == PointsToNode::ArgEscape) worklist.push(nk); } // mark all nodes reachable from ArgEscape nodes while(worklist.length() > 0) { PointsToNode* ptn = ptnode_adr(worklist.pop()); if (ptn->node_type() == PointsToNode::JavaObject) has_non_escaping_obj = true; // Non GlobalEscape uint e_cnt = ptn->edge_count(); for (uint ei = 0; ei < e_cnt; ei++) { uint npi = ptn->edge_target(ei); PointsToNode *np = ptnode_adr(npi); if (np->escape_state() < PointsToNode::ArgEscape) { np->set_escape_state(PointsToNode::ArgEscape); worklist.push(npi); } } } GrowableArray alloc_worklist; // push all NoEscape nodes on the worklist for( uint next = 0; next < cg_length; ++next ) { int nk = cg_worklist.at(next); if (ptnode_adr(nk)->escape_state() == PointsToNode::NoEscape) worklist.push(nk); } // mark all nodes reachable from NoEscape nodes while(worklist.length() > 0) { PointsToNode* ptn = ptnode_adr(worklist.pop()); if (ptn->node_type() == PointsToNode::JavaObject) has_non_escaping_obj = true; // Non GlobalEscape Node* n = ptn->_node; if (n->is_Allocate() && ptn->_scalar_replaceable ) { // Push scalar replaceable allocations on alloc_worklist // for processing in split_unique_types(). alloc_worklist.append(n); } uint e_cnt = ptn->edge_count(); for (uint ei = 0; ei < e_cnt; ei++) { uint npi = ptn->edge_target(ei); PointsToNode *np = ptnode_adr(npi); if (np->escape_state() < PointsToNode::NoEscape) { np->set_escape_state(PointsToNode::NoEscape); worklist.push(npi); } } } _collecting = false; assert(C->unique() == nodes_size(), "there should be no new ideal nodes during ConnectionGraph build"); #ifndef PRODUCT if (PrintEscapeAnalysis) { dump(); // Dump ConnectionGraph } #endif bool has_scalar_replaceable_candidates = alloc_worklist.length() > 0; if ( has_scalar_replaceable_candidates && C->AliasLevel() >= 3 && EliminateAllocations ) { // Now use the escape information to create unique types for // scalar replaceable objects. split_unique_types(alloc_worklist); if (C->failing()) return false; C->print_method("After Escape Analysis", 2); #ifdef ASSERT } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) { tty->print("=== No allocations eliminated for "); C->method()->print_short_name(); if(!EliminateAllocations) { tty->print(" since EliminateAllocations is off ==="); } else if(!has_scalar_replaceable_candidates) { tty->print(" since there are no scalar replaceable candidates ==="); } else if(C->AliasLevel() < 3) { tty->print(" since AliasLevel < 3 ==="); } tty->cr(); #endif } return has_non_escaping_obj; } // Search for objects which are not scalar replaceable. void ConnectionGraph::verify_escape_state(int nidx, VectorSet& ptset, PhaseTransform* phase) { PointsToNode* ptn = ptnode_adr(nidx); Node* n = ptn->_node; assert(n->is_AddP(), "Should be called for AddP nodes only"); // Search for objects which are not scalar replaceable. // Mark their escape state as ArgEscape to propagate the state // to referenced objects. // Note: currently there are no difference in compiler optimizations // for ArgEscape objects and NoEscape objects which are not // scalar replaceable. Compile* C = _compile; int offset = ptn->offset(); Node* base = get_addp_base(n); ptset.Clear(); PointsTo(ptset, base); int ptset_size = ptset.Size(); // Check if a oop field's initializing value is recorded and add // a corresponding NULL field's value if it is not recorded. // Connection Graph does not record a default initialization by NULL // captured by Initialize node. // // Note: it will disable scalar replacement in some cases: // // Point p[] = new Point[1]; // p[0] = new Point(); // Will be not scalar replaced // // but it will save us from incorrect optimizations in next cases: // // Point p[] = new Point[1]; // if ( x ) p[0] = new Point(); // Will be not scalar replaced // // Do a simple control flow analysis to distinguish above cases. // if (offset != Type::OffsetBot && ptset_size == 1) { uint elem = ptset.getelem(); // Allocation node's index // It does not matter if it is not Allocation node since // only non-escaping allocations are scalar replaced. if (ptnode_adr(elem)->_node->is_Allocate() && ptnode_adr(elem)->escape_state() == PointsToNode::NoEscape) { AllocateNode* alloc = ptnode_adr(elem)->_node->as_Allocate(); InitializeNode* ini = alloc->initialization(); // Check only oop fields. const Type* adr_type = n->as_AddP()->bottom_type(); BasicType basic_field_type = T_INT; if (adr_type->isa_instptr()) { ciField* field = C->alias_type(adr_type->isa_instptr())->field(); if (field != NULL) { basic_field_type = field->layout_type(); } else { // Ignore non field load (for example, klass load) } } else if (adr_type->isa_aryptr()) { const Type* elemtype = adr_type->isa_aryptr()->elem(); basic_field_type = elemtype->array_element_basic_type(); } else { // Raw pointers are used for initializing stores so skip it. assert(adr_type->isa_rawptr() && base->is_Proj() && (base->in(0) == alloc),"unexpected pointer type"); } if (basic_field_type == T_OBJECT || basic_field_type == T_NARROWOOP || basic_field_type == T_ARRAY) { Node* value = NULL; if (ini != NULL) { BasicType ft = UseCompressedOops ? T_NARROWOOP : T_OBJECT; Node* store = ini->find_captured_store(offset, type2aelembytes(ft), phase); if (store != NULL && store->is_Store()) { value = store->in(MemNode::ValueIn); } else if (ptn->edge_count() > 0) { // Are there oop stores? // Check for a store which follows allocation without branches. // For example, a volatile field store is not collected // by Initialize node. TODO: it would be nice to use idom() here. for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { store = n->fast_out(i); if (store->is_Store() && store->in(0) != NULL) { Node* ctrl = store->in(0); while(!(ctrl == ini || ctrl == alloc || ctrl == NULL || ctrl == C->root() || ctrl == C->top() || ctrl->is_Region() || ctrl->is_IfTrue() || ctrl->is_IfFalse())) { ctrl = ctrl->in(0); } if (ctrl == ini || ctrl == alloc) { value = store->in(MemNode::ValueIn); break; } } } } } if (value == NULL || value != ptnode_adr(value->_idx)->_node) { // A field's initializing value was not recorded. Add NULL. uint null_idx = UseCompressedOops ? _noop_null : _oop_null; add_pointsto_edge(nidx, null_idx); } } } } // An object is not scalar replaceable if the field which may point // to it has unknown offset (unknown element of an array of objects). // if (offset == Type::OffsetBot) { uint e_cnt = ptn->edge_count(); for (uint ei = 0; ei < e_cnt; ei++) { uint npi = ptn->edge_target(ei); set_escape_state(npi, PointsToNode::ArgEscape); ptnode_adr(npi)->_scalar_replaceable = false; } } // Currently an object is not scalar replaceable if a LoadStore node // access its field since the field value is unknown after it. // bool has_LoadStore = false; for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { Node *use = n->fast_out(i); if (use->is_LoadStore()) { has_LoadStore = true; break; } } // An object is not scalar replaceable if the address points // to unknown field (unknown element for arrays, offset is OffsetBot). // // Or the address may point to more then one object. This may produce // the false positive result (set scalar_replaceable to false) // since the flow-insensitive escape analysis can't separate // the case when stores overwrite the field's value from the case // when stores happened on different control branches. // if (ptset_size > 1 || ptset_size != 0 && (has_LoadStore || offset == Type::OffsetBot)) { for( VectorSetI j(&ptset); j.test(); ++j ) { set_escape_state(j.elem, PointsToNode::ArgEscape); ptnode_adr(j.elem)->_scalar_replaceable = false; } } } void ConnectionGraph::process_call_arguments(CallNode *call, PhaseTransform *phase) { switch (call->Opcode()) { #ifdef ASSERT case Op_Allocate: case Op_AllocateArray: case Op_Lock: case Op_Unlock: assert(false, "should be done already"); break; #endif case Op_CallLeaf: case Op_CallLeafNoFP: { // Stub calls, objects do not escape but they are not scale replaceable. // Adjust escape state for outgoing arguments. const TypeTuple * d = call->tf()->domain(); VectorSet ptset(Thread::current()->resource_area()); for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { const Type* at = d->field_at(i); Node *arg = call->in(i)->uncast(); const Type *aat = phase->type(arg); if (!arg->is_top() && at->isa_ptr() && aat->isa_ptr() && ptnode_adr(arg->_idx)->escape_state() < PointsToNode::ArgEscape) { assert(aat == Type::TOP || aat == TypePtr::NULL_PTR || aat->isa_ptr() != NULL, "expecting an Ptr"); #ifdef ASSERT if (!(call->Opcode() == Op_CallLeafNoFP && call->as_CallLeaf()->_name != NULL && (strstr(call->as_CallLeaf()->_name, "arraycopy") != 0) || call->as_CallLeaf()->_name != NULL && (strcmp(call->as_CallLeaf()->_name, "g1_wb_pre") == 0 || strcmp(call->as_CallLeaf()->_name, "g1_wb_post") == 0 )) ) { call->dump(); assert(false, "EA: unexpected CallLeaf"); } #endif set_escape_state(arg->_idx, PointsToNode::ArgEscape); if (arg->is_AddP()) { // // The inline_native_clone() case when the arraycopy stub is called // after the allocation before Initialize and CheckCastPP nodes. // // Set AddP's base (Allocate) as not scalar replaceable since // pointer to the base (with offset) is passed as argument. // arg = get_addp_base(arg); } ptset.Clear(); PointsTo(ptset, arg); for( VectorSetI j(&ptset); j.test(); ++j ) { uint pt = j.elem; set_escape_state(pt, PointsToNode::ArgEscape); } } } break; } case Op_CallStaticJava: // For a static call, we know exactly what method is being called. // Use bytecode estimator to record the call's escape affects { ciMethod *meth = call->as_CallJava()->method(); BCEscapeAnalyzer *call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL; // fall-through if not a Java method or no analyzer information if (call_analyzer != NULL) { const TypeTuple * d = call->tf()->domain(); VectorSet ptset(Thread::current()->resource_area()); bool copy_dependencies = false; for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { const Type* at = d->field_at(i); int k = i - TypeFunc::Parms; Node *arg = call->in(i)->uncast(); if (at->isa_oopptr() != NULL && ptnode_adr(arg->_idx)->escape_state() < PointsToNode::GlobalEscape) { bool global_escapes = false; bool fields_escapes = false; if (!call_analyzer->is_arg_stack(k)) { // The argument global escapes, mark everything it could point to set_escape_state(arg->_idx, PointsToNode::GlobalEscape); global_escapes = true; } else { if (!call_analyzer->is_arg_local(k)) { // The argument itself doesn't escape, but any fields might fields_escapes = true; } set_escape_state(arg->_idx, PointsToNode::ArgEscape); copy_dependencies = true; } ptset.Clear(); PointsTo(ptset, arg); for( VectorSetI j(&ptset); j.test(); ++j ) { uint pt = j.elem; if (global_escapes) { //The argument global escapes, mark everything it could point to set_escape_state(pt, PointsToNode::GlobalEscape); } else { if (fields_escapes) { // The argument itself doesn't escape, but any fields might add_edge_from_fields(pt, _phantom_object, Type::OffsetBot); } set_escape_state(pt, PointsToNode::ArgEscape); } } } } if (copy_dependencies) call_analyzer->copy_dependencies(_compile->dependencies()); break; } } default: // Fall-through here if not a Java method or no analyzer information // or some other type of call, assume the worst case: all arguments // globally escape. { // adjust escape state for outgoing arguments const TypeTuple * d = call->tf()->domain(); VectorSet ptset(Thread::current()->resource_area()); for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { const Type* at = d->field_at(i); if (at->isa_oopptr() != NULL) { Node *arg = call->in(i)->uncast(); set_escape_state(arg->_idx, PointsToNode::GlobalEscape); ptset.Clear(); PointsTo(ptset, arg); for( VectorSetI j(&ptset); j.test(); ++j ) { uint pt = j.elem; set_escape_state(pt, PointsToNode::GlobalEscape); } } } } } } void ConnectionGraph::process_call_result(ProjNode *resproj, PhaseTransform *phase) { CallNode *call = resproj->in(0)->as_Call(); uint call_idx = call->_idx; uint resproj_idx = resproj->_idx; switch (call->Opcode()) { case Op_Allocate: { Node *k = call->in(AllocateNode::KlassNode); const TypeKlassPtr *kt = k->bottom_type()->isa_klassptr(); assert(kt != NULL, "TypeKlassPtr required."); ciKlass* cik = kt->klass(); PointsToNode::EscapeState es; uint edge_to; if (cik->is_subclass_of(_compile->env()->Thread_klass()) || !cik->is_instance_klass() || // StressReflectiveCode cik->as_instance_klass()->has_finalizer()) { es = PointsToNode::GlobalEscape; edge_to = _phantom_object; // Could not be worse } else { es = PointsToNode::NoEscape; edge_to = call_idx; } set_escape_state(call_idx, es); add_pointsto_edge(resproj_idx, edge_to); _processed.set(resproj_idx); break; } case Op_AllocateArray: { Node *k = call->in(AllocateNode::KlassNode); const TypeKlassPtr *kt = k->bottom_type()->isa_klassptr(); assert(kt != NULL, "TypeKlassPtr required."); ciKlass* cik = kt->klass(); PointsToNode::EscapeState es; uint edge_to; if (!cik->is_array_klass()) { // StressReflectiveCode es = PointsToNode::GlobalEscape; edge_to = _phantom_object; } else { es = PointsToNode::NoEscape; edge_to = call_idx; int length = call->in(AllocateNode::ALength)->find_int_con(-1); if (length < 0 || length > EliminateAllocationArraySizeLimit) { // Not scalar replaceable if the length is not constant or too big. ptnode_adr(call_idx)->_scalar_replaceable = false; } } set_escape_state(call_idx, es); add_pointsto_edge(resproj_idx, edge_to); _processed.set(resproj_idx); break; } case Op_CallStaticJava: // For a static call, we know exactly what method is being called. // Use bytecode estimator to record whether the call's return value escapes { bool done = true; const TypeTuple *r = call->tf()->range(); const Type* ret_type = NULL; if (r->cnt() > TypeFunc::Parms) ret_type = r->field_at(TypeFunc::Parms); // Note: we use isa_ptr() instead of isa_oopptr() here because the // _multianewarray functions return a TypeRawPtr. if (ret_type == NULL || ret_type->isa_ptr() == NULL) { _processed.set(resproj_idx); break; // doesn't return a pointer type } ciMethod *meth = call->as_CallJava()->method(); const TypeTuple * d = call->tf()->domain(); if (meth == NULL) { // not a Java method, assume global escape set_escape_state(call_idx, PointsToNode::GlobalEscape); add_pointsto_edge(resproj_idx, _phantom_object); } else { BCEscapeAnalyzer *call_analyzer = meth->get_bcea(); bool copy_dependencies = false; if (call_analyzer->is_return_allocated()) { // Returns a newly allocated unescaped object, simply // update dependency information. // Mark it as NoEscape so that objects referenced by // it's fields will be marked as NoEscape at least. set_escape_state(call_idx, PointsToNode::NoEscape); add_pointsto_edge(resproj_idx, call_idx); copy_dependencies = true; } else if (call_analyzer->is_return_local()) { // determine whether any arguments are returned set_escape_state(call_idx, PointsToNode::NoEscape); bool ret_arg = false; for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { const Type* at = d->field_at(i); if (at->isa_oopptr() != NULL) { Node *arg = call->in(i)->uncast(); if (call_analyzer->is_arg_returned(i - TypeFunc::Parms)) { ret_arg = true; PointsToNode *arg_esp = ptnode_adr(arg->_idx); if (arg_esp->node_type() == PointsToNode::UnknownType) done = false; else if (arg_esp->node_type() == PointsToNode::JavaObject) add_pointsto_edge(resproj_idx, arg->_idx); else add_deferred_edge(resproj_idx, arg->_idx); arg_esp->_hidden_alias = true; } } } if (done && !ret_arg) { // Returns unknown object. set_escape_state(call_idx, PointsToNode::GlobalEscape); add_pointsto_edge(resproj_idx, _phantom_object); } copy_dependencies = true; } else { set_escape_state(call_idx, PointsToNode::GlobalEscape); add_pointsto_edge(resproj_idx, _phantom_object); for (uint i = TypeFunc::Parms; i < d->cnt(); i++) { const Type* at = d->field_at(i); if (at->isa_oopptr() != NULL) { Node *arg = call->in(i)->uncast(); PointsToNode *arg_esp = ptnode_adr(arg->_idx); arg_esp->_hidden_alias = true; } } } if (copy_dependencies) call_analyzer->copy_dependencies(_compile->dependencies()); } if (done) _processed.set(resproj_idx); break; } default: // Some other type of call, assume the worst case that the // returned value, if any, globally escapes. { const TypeTuple *r = call->tf()->range(); if (r->cnt() > TypeFunc::Parms) { const Type* ret_type = r->field_at(TypeFunc::Parms); // Note: we use isa_ptr() instead of isa_oopptr() here because the // _multianewarray functions return a TypeRawPtr. if (ret_type->isa_ptr() != NULL) { set_escape_state(call_idx, PointsToNode::GlobalEscape); add_pointsto_edge(resproj_idx, _phantom_object); } } _processed.set(resproj_idx); } } } // Populate Connection Graph with Ideal nodes and create simple // connection graph edges (do not need to check the node_type of inputs // or to call PointsTo() to walk the connection graph). void ConnectionGraph::record_for_escape_analysis(Node *n, PhaseTransform *phase) { if (_processed.test(n->_idx)) return; // No need to redefine node's state. if (n->is_Call()) { // Arguments to allocation and locking don't escape. if (n->is_Allocate()) { add_node(n, PointsToNode::JavaObject, PointsToNode::UnknownEscape, true); record_for_optimizer(n); } else if (n->is_Lock() || n->is_Unlock()) { // Put Lock and Unlock nodes on IGVN worklist to process them during // the first IGVN optimization when escape information is still available. record_for_optimizer(n); _processed.set(n->_idx); } else { // Don't mark as processed since call's arguments have to be processed. PointsToNode::NodeType nt = PointsToNode::UnknownType; PointsToNode::EscapeState es = PointsToNode::UnknownEscape; // Check if a call returns an object. const TypeTuple *r = n->as_Call()->tf()->range(); if (r->cnt() > TypeFunc::Parms && r->field_at(TypeFunc::Parms)->isa_ptr() && n->as_Call()->proj_out(TypeFunc::Parms) != NULL) { nt = PointsToNode::JavaObject; if (!n->is_CallStaticJava()) { // Since the called mathod is statically unknown assume // the worst case that the returned value globally escapes. es = PointsToNode::GlobalEscape; } } add_node(n, nt, es, false); } return; } // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because // ThreadLocal has RawPrt type. switch (n->Opcode()) { case Op_AddP: { add_node(n, PointsToNode::Field, PointsToNode::UnknownEscape, false); break; } case Op_CastX2P: { // "Unsafe" memory access. add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true); break; } case Op_CastPP: case Op_CheckCastPP: case Op_EncodeP: case Op_DecodeN: { add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false); int ti = n->in(1)->_idx; PointsToNode::NodeType nt = ptnode_adr(ti)->node_type(); if (nt == PointsToNode::UnknownType) { _delayed_worklist.push(n); // Process it later. break; } else if (nt == PointsToNode::JavaObject) { add_pointsto_edge(n->_idx, ti); } else { add_deferred_edge(n->_idx, ti); } _processed.set(n->_idx); break; } case Op_ConP: { // assume all pointer constants globally escape except for null PointsToNode::EscapeState es; if (phase->type(n) == TypePtr::NULL_PTR) es = PointsToNode::NoEscape; else es = PointsToNode::GlobalEscape; add_node(n, PointsToNode::JavaObject, es, true); break; } case Op_ConN: { // assume all narrow oop constants globally escape except for null PointsToNode::EscapeState es; if (phase->type(n) == TypeNarrowOop::NULL_PTR) es = PointsToNode::NoEscape; else es = PointsToNode::GlobalEscape; add_node(n, PointsToNode::JavaObject, es, true); break; } case Op_CreateEx: { // assume that all exception objects globally escape add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true); break; } case Op_LoadKlass: case Op_LoadNKlass: { add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true); break; } case Op_LoadP: case Op_LoadN: { const Type *t = phase->type(n); if (t->make_ptr() == NULL) { _processed.set(n->_idx); return; } add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false); break; } case Op_Parm: { _processed.set(n->_idx); // No need to redefine it state. uint con = n->as_Proj()->_con; if (con < TypeFunc::Parms) return; const Type *t = n->in(0)->as_Start()->_domain->field_at(con); if (t->isa_ptr() == NULL) return; // We have to assume all input parameters globally escape // (Note: passing 'false' since _processed is already set). add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, false); break; } case Op_Phi: { const Type *t = n->as_Phi()->type(); if (t->make_ptr() == NULL) { // nothing to do if not an oop or narrow oop _processed.set(n->_idx); return; } add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false); uint i; for (i = 1; i < n->req() ; i++) { Node* in = n->in(i); if (in == NULL) continue; // ignore NULL in = in->uncast(); if (in->is_top() || in == n) continue; // ignore top or inputs which go back this node int ti = in->_idx; PointsToNode::NodeType nt = ptnode_adr(ti)->node_type(); if (nt == PointsToNode::UnknownType) { break; } else if (nt == PointsToNode::JavaObject) { add_pointsto_edge(n->_idx, ti); } else { add_deferred_edge(n->_idx, ti); } } if (i >= n->req()) _processed.set(n->_idx); else _delayed_worklist.push(n); break; } case Op_Proj: { // we are only interested in the oop result projection from a call if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) { const TypeTuple *r = n->in(0)->as_Call()->tf()->range(); assert(r->cnt() > TypeFunc::Parms, "sanity"); if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) { add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false); int ti = n->in(0)->_idx; // The call may not be registered yet (since not all its inputs are registered) // if this is the projection from backbranch edge of Phi. if (ptnode_adr(ti)->node_type() != PointsToNode::UnknownType) { process_call_result(n->as_Proj(), phase); } if (!_processed.test(n->_idx)) { // The call's result may need to be processed later if the call // returns it's argument and the argument is not processed yet. _delayed_worklist.push(n); } break; } } _processed.set(n->_idx); break; } case Op_Return: { if( n->req() > TypeFunc::Parms && phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) { // Treat Return value as LocalVar with GlobalEscape escape state. add_node(n, PointsToNode::LocalVar, PointsToNode::GlobalEscape, false); int ti = n->in(TypeFunc::Parms)->_idx; PointsToNode::NodeType nt = ptnode_adr(ti)->node_type(); if (nt == PointsToNode::UnknownType) { _delayed_worklist.push(n); // Process it later. break; } else if (nt == PointsToNode::JavaObject) { add_pointsto_edge(n->_idx, ti); } else { add_deferred_edge(n->_idx, ti); } } _processed.set(n->_idx); break; } case Op_StoreP: case Op_StoreN: { const Type *adr_type = phase->type(n->in(MemNode::Address)); adr_type = adr_type->make_ptr(); if (adr_type->isa_oopptr()) { add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false); } else { Node* adr = n->in(MemNode::Address); if (adr->is_AddP() && phase->type(adr) == TypeRawPtr::NOTNULL && adr->in(AddPNode::Address)->is_Proj() && adr->in(AddPNode::Address)->in(0)->is_Allocate()) { add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false); // We are computing a raw address for a store captured // by an Initialize compute an appropriate address type. int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot); assert(offs != Type::OffsetBot, "offset must be a constant"); } else { _processed.set(n->_idx); return; } } break; } case Op_StorePConditional: case Op_CompareAndSwapP: case Op_CompareAndSwapN: { const Type *adr_type = phase->type(n->in(MemNode::Address)); adr_type = adr_type->make_ptr(); if (adr_type->isa_oopptr()) { add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false); } else { _processed.set(n->_idx); return; } break; } case Op_AryEq: case Op_StrComp: case Op_StrEquals: case Op_StrIndexOf: { // char[] arrays passed to string intrinsics are not scalar replaceable. add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false); break; } case Op_ThreadLocal: { add_node(n, PointsToNode::JavaObject, PointsToNode::ArgEscape, true); break; } default: ; // nothing to do } return; } void ConnectionGraph::build_connection_graph(Node *n, PhaseTransform *phase) { uint n_idx = n->_idx; assert(ptnode_adr(n_idx)->_node != NULL, "node should be registered"); // Don't set processed bit for AddP, LoadP, StoreP since // they may need more then one pass to process. if (_processed.test(n_idx)) return; // No need to redefine node's state. if (n->is_Call()) { CallNode *call = n->as_Call(); process_call_arguments(call, phase); _processed.set(n_idx); return; } switch (n->Opcode()) { case Op_AddP: { Node *base = get_addp_base(n); // Create a field edge to this node from everything base could point to. VectorSet ptset(Thread::current()->resource_area()); PointsTo(ptset, base); for( VectorSetI i(&ptset); i.test(); ++i ) { uint pt = i.elem; add_field_edge(pt, n_idx, address_offset(n, phase)); } break; } case Op_CastX2P: { assert(false, "Op_CastX2P"); break; } case Op_CastPP: case Op_CheckCastPP: case Op_EncodeP: case Op_DecodeN: { int ti = n->in(1)->_idx; assert(ptnode_adr(ti)->node_type() != PointsToNode::UnknownType, "all nodes should be registered"); if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) { add_pointsto_edge(n_idx, ti); } else { add_deferred_edge(n_idx, ti); } _processed.set(n_idx); break; } case Op_ConP: { assert(false, "Op_ConP"); break; } case Op_ConN: { assert(false, "Op_ConN"); break; } case Op_CreateEx: { assert(false, "Op_CreateEx"); break; } case Op_LoadKlass: case Op_LoadNKlass: { assert(false, "Op_LoadKlass"); break; } case Op_LoadP: case Op_LoadN: { const Type *t = phase->type(n); #ifdef ASSERT if (t->make_ptr() == NULL) assert(false, "Op_LoadP"); #endif Node* adr = n->in(MemNode::Address)->uncast(); Node* adr_base; if (adr->is_AddP()) { adr_base = get_addp_base(adr); } else { adr_base = adr; } // For everything "adr_base" could point to, create a deferred edge from // this node to each field with the same offset. VectorSet ptset(Thread::current()->resource_area()); PointsTo(ptset, adr_base); int offset = address_offset(adr, phase); for( VectorSetI i(&ptset); i.test(); ++i ) { uint pt = i.elem; add_deferred_edge_to_fields(n_idx, pt, offset); } break; } case Op_Parm: { assert(false, "Op_Parm"); break; } case Op_Phi: { #ifdef ASSERT const Type *t = n->as_Phi()->type(); if (t->make_ptr() == NULL) assert(false, "Op_Phi"); #endif for (uint i = 1; i < n->req() ; i++) { Node* in = n->in(i); if (in == NULL) continue; // ignore NULL in = in->uncast(); if (in->is_top() || in == n) continue; // ignore top or inputs which go back this node int ti = in->_idx; PointsToNode::NodeType nt = ptnode_adr(ti)->node_type(); assert(nt != PointsToNode::UnknownType, "all nodes should be known"); if (nt == PointsToNode::JavaObject) { add_pointsto_edge(n_idx, ti); } else { add_deferred_edge(n_idx, ti); } } _processed.set(n_idx); break; } case Op_Proj: { // we are only interested in the oop result projection from a call if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) { assert(ptnode_adr(n->in(0)->_idx)->node_type() != PointsToNode::UnknownType, "all nodes should be registered"); const TypeTuple *r = n->in(0)->as_Call()->tf()->range(); assert(r->cnt() > TypeFunc::Parms, "sanity"); if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) { process_call_result(n->as_Proj(), phase); assert(_processed.test(n_idx), "all call results should be processed"); break; } } assert(false, "Op_Proj"); break; } case Op_Return: { #ifdef ASSERT if( n->req() <= TypeFunc::Parms || !phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) { assert(false, "Op_Return"); } #endif int ti = n->in(TypeFunc::Parms)->_idx; assert(ptnode_adr(ti)->node_type() != PointsToNode::UnknownType, "node should be registered"); if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) { add_pointsto_edge(n_idx, ti); } else { add_deferred_edge(n_idx, ti); } _processed.set(n_idx); break; } case Op_StoreP: case Op_StoreN: case Op_StorePConditional: case Op_CompareAndSwapP: case Op_CompareAndSwapN: { Node *adr = n->in(MemNode::Address); const Type *adr_type = phase->type(adr)->make_ptr(); #ifdef ASSERT if (!adr_type->isa_oopptr()) assert(phase->type(adr) == TypeRawPtr::NOTNULL, "Op_StoreP"); #endif assert(adr->is_AddP(), "expecting an AddP"); Node *adr_base = get_addp_base(adr); Node *val = n->in(MemNode::ValueIn)->uncast(); // For everything "adr_base" could point to, create a deferred edge // to "val" from each field with the same offset. VectorSet ptset(Thread::current()->resource_area()); PointsTo(ptset, adr_base); for( VectorSetI i(&ptset); i.test(); ++i ) { uint pt = i.elem; add_edge_from_fields(pt, val->_idx, address_offset(adr, phase)); } break; } case Op_AryEq: case Op_StrComp: case Op_StrEquals: case Op_StrIndexOf: { // char[] arrays passed to string intrinsic do not escape but // they are not scalar replaceable. Adjust escape state for them. // Start from in(2) edge since in(1) is memory edge. for (uint i = 2; i < n->req(); i++) { Node* adr = n->in(i)->uncast(); const Type *at = phase->type(adr); if (!adr->is_top() && at->isa_ptr()) { assert(at == Type::TOP || at == TypePtr::NULL_PTR || at->isa_ptr() != NULL, "expecting an Ptr"); if (adr->is_AddP()) { adr = get_addp_base(adr); } // Mark as ArgEscape everything "adr" could point to. set_escape_state(adr->_idx, PointsToNode::ArgEscape); } } _processed.set(n_idx); break; } case Op_ThreadLocal: { assert(false, "Op_ThreadLocal"); break; } default: // This method should be called only for EA specific nodes. ShouldNotReachHere(); } } #ifndef PRODUCT void ConnectionGraph::dump() { bool first = true; uint size = nodes_size(); for (uint ni = 0; ni < size; ni++) { PointsToNode *ptn = ptnode_adr(ni); PointsToNode::NodeType ptn_type = ptn->node_type(); if (ptn_type != PointsToNode::JavaObject || ptn->_node == NULL) continue; PointsToNode::EscapeState es = escape_state(ptn->_node); if (ptn->_node->is_Allocate() && (es == PointsToNode::NoEscape || Verbose)) { if (first) { tty->cr(); tty->print("======== Connection graph for "); _compile->method()->print_short_name(); tty->cr(); first = false; } tty->print("%6d ", ni); ptn->dump(); // Print all locals which reference this allocation for (uint li = ni; li < size; li++) { PointsToNode *ptn_loc = ptnode_adr(li); PointsToNode::NodeType ptn_loc_type = ptn_loc->node_type(); if ( ptn_loc_type == PointsToNode::LocalVar && ptn_loc->_node != NULL && ptn_loc->edge_count() == 1 && ptn_loc->edge_target(0) == ni ) { ptnode_adr(li)->dump(false); } } if (Verbose) { // Print all fields which reference this allocation for (uint i = 0; i < ptn->edge_count(); i++) { uint ei = ptn->edge_target(i); ptnode_adr(ei)->dump(false); } } tty->cr(); } } } #endif