| /* |
| * Copyright (c) 2005, 2013, 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 "libadt/vectset.hpp" |
| #include "opto/addnode.hpp" |
| #include "opto/callnode.hpp" |
| #include "opto/cfgnode.hpp" |
| #include "opto/compile.hpp" |
| #include "opto/connode.hpp" |
| #include "opto/locknode.hpp" |
| #include "opto/loopnode.hpp" |
| #include "opto/macro.hpp" |
| #include "opto/memnode.hpp" |
| #include "opto/node.hpp" |
| #include "opto/phaseX.hpp" |
| #include "opto/rootnode.hpp" |
| #include "opto/runtime.hpp" |
| #include "opto/subnode.hpp" |
| #include "opto/type.hpp" |
| #include "runtime/sharedRuntime.hpp" |
| |
| |
| // |
| // 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::copy_call_debug_info(CallNode *oldcall, CallNode * newcall) { |
| // Copy debug information and adjust JVMState information |
| uint old_dbg_start = oldcall->tf()->domain()->cnt(); |
| uint new_dbg_start = newcall->tf()->domain()->cnt(); |
| int jvms_adj = new_dbg_start - old_dbg_start; |
| assert (new_dbg_start == newcall->req(), "argument count mismatch"); |
| |
| // SafePointScalarObject node could be referenced several times in debug info. |
| // Use Dict to record cloned nodes. |
| Dict* sosn_map = new Dict(cmpkey,hashkey); |
| for (uint i = old_dbg_start; i < oldcall->req(); i++) { |
| Node* old_in = oldcall->in(i); |
| // Clone old SafePointScalarObjectNodes, adjusting their field contents. |
| if (old_in != NULL && old_in->is_SafePointScalarObject()) { |
| SafePointScalarObjectNode* old_sosn = old_in->as_SafePointScalarObject(); |
| uint old_unique = C->unique(); |
| Node* new_in = old_sosn->clone(sosn_map); |
| if (old_unique != C->unique()) { // New node? |
| new_in->set_req(0, C->root()); // reset control edge |
| new_in = transform_later(new_in); // Register new node. |
| } |
| old_in = new_in; |
| } |
| newcall->add_req(old_in); |
| } |
| |
| newcall->set_jvms(oldcall->jvms()); |
| for (JVMState *jvms = newcall->jvms(); jvms != NULL; jvms = jvms->caller()) { |
| jvms->set_map(newcall); |
| jvms->set_locoff(jvms->locoff()+jvms_adj); |
| jvms->set_stkoff(jvms->stkoff()+jvms_adj); |
| jvms->set_monoff(jvms->monoff()+jvms_adj); |
| jvms->set_scloff(jvms->scloff()+jvms_adj); |
| jvms->set_endoff(jvms->endoff()+jvms_adj); |
| } |
| } |
| |
| Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word, int mask, int bits, bool return_fast_path) { |
| Node* cmp; |
| if (mask != 0) { |
| Node* and_node = transform_later(new (C) AndXNode(word, MakeConX(mask))); |
| cmp = transform_later(new (C) CmpXNode(and_node, MakeConX(bits))); |
| } else { |
| cmp = word; |
| } |
| Node* bol = transform_later(new (C) BoolNode(cmp, BoolTest::ne)); |
| IfNode* iff = new (C) IfNode( ctrl, bol, PROB_MIN, COUNT_UNKNOWN ); |
| transform_later(iff); |
| |
| // Fast path taken. |
| Node *fast_taken = transform_later( new (C) IfFalseNode(iff) ); |
| |
| // Fast path not-taken, i.e. slow path |
| Node *slow_taken = transform_later( new (C) 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* oldcall, CallNode* call) { |
| // 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_call_type, address slow_call, const char* leaf_name, Node* slow_path, Node* parm0, Node* parm1) { |
| |
| // Slow-path call |
| CallNode *call = leaf_name |
| ? (CallNode*)new (C) CallLeafNode ( slow_call_type, slow_call, leaf_name, TypeRawPtr::BOTTOM ) |
| : (CallNode*)new (C) CallStaticJavaNode( slow_call_type, slow_call, OptoRuntime::stub_name(slow_call), oldcall->jvms()->bci(), TypeRawPtr::BOTTOM ); |
| |
| // 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); |
| copy_call_debug_info(oldcall, call); |
| call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON. |
| _igvn.replace_node(oldcall, call); |
| transform_later(call); |
| |
| return call; |
| } |
| |
| void PhaseMacroExpand::extract_call_projections(CallNode *call) { |
| _fallthroughproj = NULL; |
| _fallthroughcatchproj = NULL; |
| _ioproj_fallthrough = NULL; |
| _ioproj_catchall = NULL; |
| _catchallcatchproj = NULL; |
| _memproj_fallthrough = NULL; |
| _memproj_catchall = NULL; |
| _resproj = NULL; |
| for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) { |
| ProjNode *pn = call->fast_out(i)->as_Proj(); |
| switch (pn->_con) { |
| case TypeFunc::Control: |
| { |
| // For Control (fallthrough) and I_O (catch_all_index) we have CatchProj -> Catch -> Proj |
| _fallthroughproj = pn; |
| DUIterator_Fast jmax, j = pn->fast_outs(jmax); |
| const Node *cn = pn->fast_out(j); |
| if (cn->is_Catch()) { |
| ProjNode *cpn = NULL; |
| for (DUIterator_Fast kmax, k = cn->fast_outs(kmax); k < kmax; k++) { |
| cpn = cn->fast_out(k)->as_Proj(); |
| assert(cpn->is_CatchProj(), "must be a CatchProjNode"); |
| if (cpn->_con == CatchProjNode::fall_through_index) |
| _fallthroughcatchproj = cpn; |
| else { |
| assert(cpn->_con == CatchProjNode::catch_all_index, "must be correct index."); |
| _catchallcatchproj = cpn; |
| } |
| } |
| } |
| break; |
| } |
| case TypeFunc::I_O: |
| if (pn->_is_io_use) |
| _ioproj_catchall = pn; |
| else |
| _ioproj_fallthrough = pn; |
| break; |
| case TypeFunc::Memory: |
| if (pn->_is_io_use) |
| _memproj_catchall = pn; |
| else |
| _memproj_fallthrough = pn; |
| break; |
| case TypeFunc::Parms: |
| _resproj = pn; |
| break; |
| default: |
| assert(false, "unexpected projection from allocation node."); |
| } |
| } |
| |
| } |
| |
| // Eliminate a card mark sequence. p2x is a ConvP2XNode |
| void PhaseMacroExpand::eliminate_card_mark(Node* p2x) { |
| assert(p2x->Opcode() == Op_CastP2X, "ConvP2XNode required"); |
| if (!UseG1GC) { |
| // vanilla/CMS post barrier |
| Node *shift = p2x->unique_out(); |
| Node *addp = shift->unique_out(); |
| for (DUIterator_Last jmin, j = addp->last_outs(jmin); j >= jmin; --j) { |
| Node *mem = addp->last_out(j); |
| if (UseCondCardMark && mem->is_Load()) { |
| assert(mem->Opcode() == Op_LoadB, "unexpected code shape"); |
| // The load is checking if the card has been written so |
| // replace it with zero to fold the test. |
| _igvn.replace_node(mem, intcon(0)); |
| continue; |
| } |
| assert(mem->is_Store(), "store required"); |
| _igvn.replace_node(mem, mem->in(MemNode::Memory)); |
| } |
| } else { |
| // G1 pre/post barriers |
| assert(p2x->outcnt() <= 2, "expects 1 or 2 users: Xor and URShift nodes"); |
| // It could be only one user, URShift node, in Object.clone() instrinsic |
| // but the new allocation is passed to arraycopy stub and it could not |
| // be scalar replaced. So we don't check the case. |
| |
| // An other case of only one user (Xor) is when the value check for NULL |
| // in G1 post barrier is folded after CCP so the code which used URShift |
| // is removed. |
| |
| // Take Region node before eliminating post barrier since it also |
| // eliminates CastP2X node when it has only one user. |
| Node* this_region = p2x->in(0); |
| assert(this_region != NULL, ""); |
| |
| // Remove G1 post barrier. |
| |
| // Search for CastP2X->Xor->URShift->Cmp path which |
| // checks if the store done to a different from the value's region. |
| // And replace Cmp with #0 (false) to collapse G1 post barrier. |
| Node* xorx = NULL; |
| for (DUIterator_Fast imax, i = p2x->fast_outs(imax); i < imax; i++) { |
| Node* u = p2x->fast_out(i); |
| if (u->Opcode() == Op_XorX) { |
| xorx = u; |
| break; |
| } |
| } |
| assert(xorx != NULL, "missing G1 post barrier"); |
| Node* shift = xorx->unique_out(); |
| Node* cmpx = shift->unique_out(); |
| assert(cmpx->is_Cmp() && cmpx->unique_out()->is_Bool() && |
| cmpx->unique_out()->as_Bool()->_test._test == BoolTest::ne, |
| "missing region check in G1 post barrier"); |
| _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ)); |
| |
| // Remove G1 pre barrier. |
| |
| // Search "if (marking != 0)" check and set it to "false". |
| // There is no G1 pre barrier if previous stored value is NULL |
| // (for example, after initialization). |
| if (this_region->is_Region() && this_region->req() == 3) { |
| int ind = 1; |
| if (!this_region->in(ind)->is_IfFalse()) { |
| ind = 2; |
| } |
| if (this_region->in(ind)->is_IfFalse()) { |
| Node* bol = this_region->in(ind)->in(0)->in(1); |
| assert(bol->is_Bool(), ""); |
| cmpx = bol->in(1); |
| if (bol->as_Bool()->_test._test == BoolTest::ne && |
| cmpx->is_Cmp() && cmpx->in(2) == intcon(0) && |
| cmpx->in(1)->is_Load()) { |
| Node* adr = cmpx->in(1)->as_Load()->in(MemNode::Address); |
| const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + |
| PtrQueue::byte_offset_of_active()); |
| if (adr->is_AddP() && adr->in(AddPNode::Base) == top() && |
| adr->in(AddPNode::Address)->Opcode() == Op_ThreadLocal && |
| adr->in(AddPNode::Offset) == MakeConX(marking_offset)) { |
| _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ)); |
| } |
| } |
| } |
| } |
| // Now CastP2X can be removed since it is used only on dead path |
| // which currently still alive until igvn optimize it. |
| assert(p2x->outcnt() == 0 || p2x->unique_out()->Opcode() == Op_URShiftX, ""); |
| _igvn.replace_node(p2x, top()); |
| } |
| } |
| |
| // 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 *alloc, PhaseGVN *phase) { |
| 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)) { |
| mem = call->in(TypeFunc::Memory); |
| } |
| mem = in->in(TypeFunc::Memory); |
| } else if (in->is_MemBar()) { |
| mem = in->in(TypeFunc::Memory); |
| } else { |
| assert(false, "unexpected projection"); |
| } |
| } else if (mem->is_Store()) { |
| const TypePtr* atype = mem->as_Store()->adr_type(); |
| int adr_idx = Compile::current()->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, "sanity"); |
| adr = mem->in(3); // Destination array |
| } |
| const TypePtr* atype = adr->bottom_type()->is_ptr(); |
| int adr_idx = Compile::current()->get_alias_index(atype); |
| if (adr_idx == alias_idx) { |
| assert(false, "Object is not scalar replaceable if a LoadStore node access its field"); |
| return NULL; |
| } |
| mem = mem->in(MemNode::Memory); |
| } else { |
| return mem; |
| } |
| assert(mem != orig_mem, "dead memory loop"); |
| } |
| } |
| |
| // |
| // 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 limied 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_type, const TypeOopPtr *adr_t, Node *alloc, Node_Stack *value_phis, int level) { |
| 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, instance_id, alias_idx, offset)) { |
| 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(TypeFunc::Memory); |
| Node *alloc_mem = alloc->in(TypeFunc::Memory); |
| |
| uint length = mem->req(); |
| GrowableArray <Node *> values(length, length, NULL, false); |
| |
| // create a new Phi for the value |
| PhiNode *phi = new (C) PhiNode(mem->in(0), phi_type, NULL, instance_id, alias_idx, offset); |
| 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()) { |
| values.at_put(j, val->in(MemNode::ValueIn)); |
| } 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, "sanity"); |
| assert(false, "Object is not scalar replaceable if a LoadStore node access its field"); |
| return NULL; |
| } else { |
| #ifdef ASSERT |
| val->dump(); |
| assert(false, "unknown node on this path"); |
| #endif |
| 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, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, Node *alloc) { |
| 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(TypeFunc::Memory); |
| Node *alloc_ctrl = alloc->in(TypeFunc::Control); |
| Node *alloc_mem = alloc->in(TypeFunc::Memory); |
| Arena *a = Thread::current()->resource_area(); |
| VectorSet visited(a); |
| |
| |
| 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 slice"); |
| 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 { |
| 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()) { |
| return mem->in(MemNode::ValueIn); |
| } else if (mem->is_Phi()) { |
| // attempt to produce a Phi reflecting the values on the input paths of the Phi |
| Node_Stack value_phis(a, 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(); |
| } |
| } |
| } |
| } |
| // Something go wrong. |
| return NULL; |
| } |
| |
| // Check the possibility of scalar replacement. |
| bool PhaseMacroExpand::can_eliminate_allocation(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) { |
| // 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) { |
| 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 referrence";) |
| 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) { |
| 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 referrence";) |
| } |
| can_eliminate = false; |
| } |
| } |
| } 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 <SafePointNode *>& safepoints) { |
| GrowableArray <SafePointNode *> safepoints_done; |
| |
| ciKlass* klass = NULL; |
| ciInstanceKlass* iklass = NULL; |
| int nfields = 0; |
| int array_base; |
| int element_size; |
| BasicType basic_elem_type; |
| ciType* elem_type; |
| |
| Node* res = alloc->result_cast(); |
| 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) { |
| klass = res_type->klass(); |
| if (res_type->isa_instptr()) { |
| // find the fields of the class which will be needed for safepoint debug information |
| assert(klass->is_instance_klass(), "must be an instance klass."); |
| iklass = klass->as_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(klass->is_array_klass() && nfields >= 0, "must be an array klass."); |
| elem_type = klass->as_array_klass()->element_type(); |
| basic_elem_type = elem_type->basic_type(); |
| array_base = arrayOopDesc::base_offset_in_bytes(basic_elem_type); |
| element_size = type2aelembytes(basic_elem_type); |
| } |
| } |
| // |
| // Process the safepoint uses |
| // |
| while (safepoints.length() > 0) { |
| SafePointNode* sfpt = safepoints.pop(); |
| Node* mem = sfpt->memory(); |
| 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 (C) 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(); |
| elem_type = field->type(); |
| basic_elem_type = field->layout_type(); |
| } else { |
| offset = array_base + j * (intptr_t)element_size; |
| } |
| |
| const Type *field_type; |
| // The next code is taken from Parse::do_get_xxx(). |
| if (basic_elem_type == T_OBJECT || basic_elem_type == T_ARRAY) { |
| if (!elem_type->is_loaded()) { |
| field_type = TypeInstPtr::BOTTOM; |
| } else if (field != NULL && field->is_constant() && field->is_static()) { |
| // This can happen if the constant oop is non-perm. |
| 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); |
| } |
| |
| const TypeOopPtr *field_addr_type = res_type->add_offset(offset)->isa_oopptr(); |
| |
| Node *field_val = value_from_mem(mem, basic_elem_type, field_type, field_addr_type, alloc); |
| 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--); |
| } |
| // 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); |
| } |
| } |
| } |
| } |
| #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 (C) 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); |
| safepoints_done.append_if_missing(sfpt); // keep it for rollback |
| } |
| return true; |
| } |
| |
| // 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_card_mark(n); |
| } |
| k -= (oc2 - use->outcnt()); |
| } |
| } else { |
| eliminate_card_mark(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 (_resproj != NULL && _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 = _resproj->fast_outs(jmax); j < jmax; j++) { |
| Node *use = _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 = _resproj->last_outs(jmin); j >= jmin; ) { |
| Node *use = _resproj->last_out(j); |
| uint oc1 = _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(TypeFunc::Control); |
| if (ctrl_proj != NULL) { |
| assert(init->in(TypeFunc::Control) == _fallthroughcatchproj, "allocation control projection"); |
| _igvn.replace_node(ctrl_proj, _fallthroughcatchproj); |
| } |
| Node *mem_proj = init->proj_out(TypeFunc::Memory); |
| if (mem_proj != NULL) { |
| Node *mem = init->in(TypeFunc::Memory); |
| #ifdef ASSERT |
| if (mem->is_MergeMem()) { |
| assert(mem->in(TypeFunc::Memory) == _memproj_fallthrough, "allocation memory projection"); |
| } else { |
| assert(mem == _memproj_fallthrough, "allocation memory projection"); |
| } |
| #endif |
| _igvn.replace_node(mem_proj, mem); |
| } |
| } else { |
| assert(false, "only Initialize or AddP expected"); |
| } |
| j -= (oc1 - _resproj->outcnt()); |
| } |
| } |
| if (_fallthroughcatchproj != NULL) { |
| _igvn.replace_node(_fallthroughcatchproj, alloc->in(TypeFunc::Control)); |
| } |
| if (_memproj_fallthrough != NULL) { |
| _igvn.replace_node(_memproj_fallthrough, alloc->in(TypeFunc::Memory)); |
| } |
| if (_memproj_catchall != NULL) { |
| _igvn.replace_node(_memproj_catchall, C->top()); |
| } |
| if (_ioproj_fallthrough != NULL) { |
| _igvn.replace_node(_ioproj_fallthrough, alloc->in(TypeFunc::I_O)); |
| } |
| if (_ioproj_catchall != NULL) { |
| _igvn.replace_node(_ioproj_catchall, C->top()); |
| } |
| if (_catchallcatchproj != NULL) { |
| _igvn.replace_node(_catchallcatchproj, C->top()); |
| } |
| } |
| |
| bool PhaseMacroExpand::eliminate_allocate_node(AllocateNode *alloc) { |
| 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 replacable status. |
| bool boxing_alloc = C->eliminate_boxing() && |
| tklass->klass()->is_instance_klass() && |
| tklass->klass()->as_instance_klass()->is_box_klass(); |
| if (!alloc->_is_scalar_replaceable && (!boxing_alloc || (res != NULL))) { |
| return false; |
| } |
| |
| extract_call_projections(alloc); |
| |
| 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->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(TypeFunc::Parms) != NULL) { |
| return false; |
| } |
| |
| extract_call_projections(boxing); |
| |
| 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->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; |
| } |
| |
| //---------------------------set_eden_pointers------------------------- |
| void PhaseMacroExpand::set_eden_pointers(Node* &eden_top_adr, Node* &eden_end_adr) { |
| if (UseTLAB) { // Private allocation: load from TLS |
| Node* thread = transform_later(new (C) ThreadLocalNode()); |
| int tlab_top_offset = in_bytes(JavaThread::tlab_top_offset()); |
| int tlab_end_offset = in_bytes(JavaThread::tlab_end_offset()); |
| eden_top_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_top_offset); |
| eden_end_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_end_offset); |
| } else { // Shared allocation: load from globals |
| CollectedHeap* ch = Universe::heap(); |
| address top_adr = (address)ch->top_addr(); |
| address end_adr = (address)ch->end_addr(); |
| eden_top_adr = makecon(TypeRawPtr::make(top_adr)); |
| eden_end_adr = basic_plus_adr(eden_top_adr, end_adr - top_adr); |
| } |
| } |
| |
| |
| Node* PhaseMacroExpand::make_load(Node* ctl, Node* mem, Node* base, int offset, const Type* value_type, BasicType bt) { |
| 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); |
| transform_later(value); |
| return value; |
| } |
| |
| |
| Node* PhaseMacroExpand::make_store(Node* ctl, Node* mem, Node* base, int offset, Node* value, BasicType bt) { |
| Node* adr = basic_plus_adr(base, offset); |
| mem = StoreNode::make(_igvn, ctl, mem, adr, NULL, value, bt); |
| 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* 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; |
| Node *result_phi_rawmem; |
| Node *result_phi_rawoop; |
| Node *result_phi_i_o; |
| |
| // The initial slow comparison is a size check, the comparison |
| // we want to do is a BoolTest::gt |
| bool always_slow = false; |
| int tv = _igvn.find_int_con(initial_slow_test, -1); |
| if (tv >= 0) { |
| always_slow = (tv == 1); |
| initial_slow_test = NULL; |
| } else { |
| initial_slow_test = BoolNode::make_predicate(initial_slow_test, &_igvn); |
| } |
| |
| if (C->env()->dtrace_alloc_probes() || |
| !UseTLAB && (!Universe::heap()->supports_inline_contig_alloc() || |
| (UseConcMarkSweepGC && CMSIncrementalMode))) { |
| // Force slow-path allocation |
| always_slow = true; |
| initial_slow_test = NULL; |
| } |
| |
| |
| enum { too_big_or_final_path = 1, need_gc_path = 2 }; |
| Node *slow_region = NULL; |
| Node *toobig_false = ctrl; |
| |
| assert (initial_slow_test == NULL || !always_slow, "arguments must be consistent"); |
| // generate the initial test if necessary |
| if (initial_slow_test != NULL ) { |
| slow_region = new (C) 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 (C) 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 (C) IfTrueNode( toobig_iff ); |
| transform_later(toobig_true); |
| slow_region ->init_req( too_big_or_final_path, toobig_true ); |
| toobig_false = new (C) IfFalseNode( toobig_iff ); |
| transform_later(toobig_false); |
| } else { // No initial test, just fall into next case |
| toobig_false = ctrl; |
| debug_only(slow_region = NodeSentinel); |
| } |
| |
| 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 (!always_slow) { |
| // Fast path modifies only raw memory. |
| if (mem->is_MergeMem()) { |
| mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw); |
| } |
| |
| Node* eden_top_adr; |
| Node* eden_end_adr; |
| |
| set_eden_pointers(eden_top_adr, eden_end_adr); |
| |
| // Load Eden::end. Loop invariant and hoisted. |
| // |
| // Note: We set the control input on "eden_end" and "old_eden_top" when using |
| // a TLAB to work around a bug where these values were being moved across |
| // a safepoint. These are not oops, so they cannot be include in the oop |
| // map, but they can be changed by a GC. The proper way to fix this would |
| // be to set the raw memory state when generating a SafepointNode. However |
| // this will require extensive changes to the loop optimization in order to |
| // prevent a degradation of the optimization. |
| // See comment in memnode.hpp, around line 227 in class LoadPNode. |
| Node *eden_end = make_load(ctrl, mem, eden_end_adr, 0, TypeRawPtr::BOTTOM, T_ADDRESS); |
| |
| // allocate the Region and Phi nodes for the result |
| result_region = new (C) RegionNode(3); |
| result_phi_rawmem = new (C) PhiNode(result_region, Type::MEMORY, TypeRawPtr::BOTTOM); |
| result_phi_rawoop = new (C) PhiNode(result_region, TypeRawPtr::BOTTOM); |
| result_phi_i_o = new (C) PhiNode(result_region, Type::ABIO); // I/O is used for Prefetch |
| |
| // We need a Region for the loop-back contended case. |
| enum { fall_in_path = 1, contended_loopback_path = 2 }; |
| Node *contended_region; |
| Node *contended_phi_rawmem; |
| if (UseTLAB) { |
| contended_region = toobig_false; |
| contended_phi_rawmem = mem; |
| } else { |
| contended_region = new (C) RegionNode(3); |
| contended_phi_rawmem = new (C) PhiNode(contended_region, Type::MEMORY, TypeRawPtr::BOTTOM); |
| // Now handle the passing-too-big test. We fall into the contended |
| // loop-back merge point. |
| contended_region ->init_req(fall_in_path, toobig_false); |
| contended_phi_rawmem->init_req(fall_in_path, mem); |
| transform_later(contended_region); |
| transform_later(contended_phi_rawmem); |
| } |
| |
| // Load(-locked) the heap top. |
| // See note above concerning the control input when using a TLAB |
| Node *old_eden_top = UseTLAB |
| ? new (C) LoadPNode (ctrl, contended_phi_rawmem, eden_top_adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM) |
| : new (C) LoadPLockedNode(contended_region, contended_phi_rawmem, eden_top_adr); |
| |
| transform_later(old_eden_top); |
| // Add to heap top to get a new heap top |
| Node *new_eden_top = new (C) AddPNode(top(), old_eden_top, size_in_bytes); |
| transform_later(new_eden_top); |
| // Check for needing a GC; compare against heap end |
| Node *needgc_cmp = new (C) CmpPNode(new_eden_top, eden_end); |
| transform_later(needgc_cmp); |
| Node *needgc_bol = new (C) BoolNode(needgc_cmp, BoolTest::ge); |
| transform_later(needgc_bol); |
| IfNode *needgc_iff = new (C) IfNode(contended_region, needgc_bol, PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN); |
| transform_later(needgc_iff); |
| |
| // Plug the failing-heap-space-need-gc test into the slow-path region |
| Node *needgc_true = new (C) IfTrueNode(needgc_iff); |
| transform_later(needgc_true); |
| if (initial_slow_test) { |
| slow_region->init_req(need_gc_path, needgc_true); |
| // This completes all paths into the slow merge point |
| 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_true; |
| } |
| // No need for a GC. Setup for the Store-Conditional |
| Node *needgc_false = new (C) IfFalseNode(needgc_iff); |
| transform_later(needgc_false); |
| |
| // 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); |
| |
| i_o = prefetch_allocation(i_o, needgc_false, contended_phi_rawmem, |
| old_eden_top, new_eden_top, length); |
| |
| // Name successful fast-path variables |
| Node* fast_oop = old_eden_top; |
| Node* fast_oop_ctrl; |
| Node* fast_oop_rawmem; |
| |
| // Store (-conditional) the modified eden top back down. |
| // StorePConditional produces flags for a test PLUS a modified raw |
| // memory state. |
| if (UseTLAB) { |
| Node* store_eden_top = |
| new (C) StorePNode(needgc_false, contended_phi_rawmem, eden_top_adr, |
| TypeRawPtr::BOTTOM, new_eden_top); |
| transform_later(store_eden_top); |
| fast_oop_ctrl = needgc_false; // No contention, so this is the fast path |
| fast_oop_rawmem = store_eden_top; |
| } else { |
| Node* store_eden_top = |
| new (C) StorePConditionalNode(needgc_false, contended_phi_rawmem, eden_top_adr, |
| new_eden_top, fast_oop/*old_eden_top*/); |
| transform_later(store_eden_top); |
| Node *contention_check = new (C) BoolNode(store_eden_top, BoolTest::ne); |
| transform_later(contention_check); |
| store_eden_top = new (C) SCMemProjNode(store_eden_top); |
| transform_later(store_eden_top); |
| |
| // If not using TLABs, check to see if there was contention. |
| IfNode *contention_iff = new (C) IfNode (needgc_false, contention_check, PROB_MIN, COUNT_UNKNOWN); |
| transform_later(contention_iff); |
| Node *contention_true = new (C) IfTrueNode(contention_iff); |
| transform_later(contention_true); |
| // If contention, loopback and try again. |
| contended_region->init_req(contended_loopback_path, contention_true); |
| contended_phi_rawmem->init_req(contended_loopback_path, store_eden_top); |
| |
| // Fast-path succeeded with no contention! |
| Node *contention_false = new (C) IfFalseNode(contention_iff); |
| transform_later(contention_false); |
| fast_oop_ctrl = contention_false; |
| |
| // Bump total allocated bytes for this thread |
| Node* thread = new (C) ThreadLocalNode(); |
| transform_later(thread); |
| Node* alloc_bytes_adr = basic_plus_adr(top()/*not oop*/, thread, |
| in_bytes(JavaThread::allocated_bytes_offset())); |
| Node* alloc_bytes = make_load(fast_oop_ctrl, store_eden_top, alloc_bytes_adr, |
| 0, TypeLong::LONG, T_LONG); |
| #ifdef _LP64 |
| Node* alloc_size = size_in_bytes; |
| #else |
| Node* alloc_size = new (C) ConvI2LNode(size_in_bytes); |
| transform_later(alloc_size); |
| #endif |
| Node* new_alloc_bytes = new (C) AddLNode(alloc_bytes, alloc_size); |
| transform_later(new_alloc_bytes); |
| fast_oop_rawmem = make_store(fast_oop_ctrl, store_eden_top, alloc_bytes_adr, |
| 0, new_alloc_bytes, T_LONG); |
| } |
| |
| InitializeNode* init = alloc->initialization(); |
| fast_oop_rawmem = initialize_object(alloc, |
| fast_oop_ctrl, fast_oop_rawmem, fast_oop, |
| klass_node, length, size_in_bytes); |
| |
| // 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. 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. |
| if (init == NULL || (!init->is_complete_with_arraycopy() && !init->does_not_escape())) { |
| 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 (C) ProjNode(mb,TypeFunc::Control); |
| transform_later(fast_oop_ctrl); |
| fast_oop_rawmem = new (C) 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(TypeFunc::Control); |
| Node* init_mem = init->proj_out(TypeFunc::Memory); |
| |
| MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot); |
| transform_later(mb); |
| |
| Node* ctrl = new (C) ProjNode(init,TypeFunc::Control); |
| transform_later(ctrl); |
| Node* mem = new (C) 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 (C) ProjNode(mb,TypeFunc::Control); |
| transform_later(ctrl); |
| mem = new (C) 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 |
| _igvn.replace_node(init_ctrl, ctrl); |
| _igvn.replace_node(init_mem, mem); |
| } |
| } |
| |
| if (C->env()->dtrace_extended_probes()) { |
| // Slow-path call |
| int size = TypeFunc::Parms + 2; |
| CallLeafNode *call = new (C) CallLeafNode(OptoRuntime::dtrace_object_alloc_Type(), |
| CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_object_alloc_base), |
| "dtrace_object_alloc", |
| TypeRawPtr::BOTTOM); |
| |
| // Get base of thread-local storage area |
| Node* thread = new (C) ThreadLocalNode(); |
| transform_later(thread); |
| |
| call->init_req(TypeFunc::Parms+0, thread); |
| call->init_req(TypeFunc::Parms+1, fast_oop); |
| call->init_req(TypeFunc::Control, fast_oop_ctrl); |
| call->init_req(TypeFunc::I_O , top()); // does no i/o |
| call->init_req(TypeFunc::Memory , fast_oop_rawmem); |
| call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr)); |
| call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr)); |
| transform_later(call); |
| fast_oop_ctrl = new (C) ProjNode(call,TypeFunc::Control); |
| transform_later(fast_oop_ctrl); |
| fast_oop_rawmem = new (C) ProjNode(call,TypeFunc::Memory); |
| transform_later(fast_oop_rawmem); |
| } |
| |
| // Plug in the successful fast-path into the result merge point |
| result_region ->init_req(fast_result_path, fast_oop_ctrl); |
| result_phi_rawoop->init_req(fast_result_path, fast_oop); |
| 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 (C) CallStaticJavaNode(slow_call_type, slow_call_address, |
| OptoRuntime::stub_name(slow_call_address), |
| alloc->jvms()->bci(), |
| 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 |
| copy_call_debug_info((CallNode *) alloc, call); |
| if (!always_slow) { |
| 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. |
| // |
| extract_call_projections(call); |
| |
| // 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 (!always_slow && _memproj_fallthrough != NULL) { |
| for (DUIterator_Fast imax, i = _memproj_fallthrough->fast_outs(imax); i < imax; i++) { |
| Node *use = _memproj_fallthrough->fast_out(i); |
| _igvn.rehash_node_delayed(use); |
| imax -= replace_input(use, _memproj_fallthrough, result_phi_rawmem); |
| // back up iterator |
| --i; |
| } |
| } |
| // Now change uses of _memproj_catchall to use _memproj_fallthrough and delete |
| // _memproj_catchall so we end up with a call that has only 1 memory projection. |
| if (_memproj_catchall != NULL ) { |
| if (_memproj_fallthrough == NULL) { |
| _memproj_fallthrough = new (C) ProjNode(call, TypeFunc::Memory); |
| transform_later(_memproj_fallthrough); |
| } |
| for (DUIterator_Fast imax, i = _memproj_catchall->fast_outs(imax); i < imax; i++) { |
| Node *use = _memproj_catchall->fast_out(i); |
| _igvn.rehash_node_delayed(use); |
| imax -= replace_input(use, _memproj_catchall, _memproj_fallthrough); |
| // back up iterator |
| --i; |
| } |
| assert(_memproj_catchall->outcnt() == 0, "all uses must be deleted"); |
| _igvn.remove_dead_node(_memproj_catchall); |
| } |
| |
| // 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 (_ioproj_fallthrough != NULL) { |
| for (DUIterator_Fast imax, i = _ioproj_fallthrough->fast_outs(imax); i < imax; i++) { |
| Node *use = _ioproj_fallthrough->fast_out(i); |
| _igvn.rehash_node_delayed(use); |
| imax -= replace_input(use, _ioproj_fallthrough, result_phi_i_o); |
| // back up iterator |
| --i; |
| } |
| } |
| // Now change uses of _ioproj_catchall to use _ioproj_fallthrough and delete |
| // _ioproj_catchall so we end up with a call that has only 1 i_o projection. |
| if (_ioproj_catchall != NULL ) { |
| if (_ioproj_fallthrough == NULL) { |
| _ioproj_fallthrough = new (C) ProjNode(call, TypeFunc::I_O); |
| transform_later(_ioproj_fallthrough); |
| } |
| for (DUIterator_Fast imax, i = _ioproj_catchall->fast_outs(imax); i < imax; i++) { |
| Node *use = _ioproj_catchall->fast_out(i); |
| _igvn.rehash_node_delayed(use); |
| imax -= replace_input(use, _ioproj_catchall, _ioproj_fallthrough); |
| // back up iterator |
| --i; |
| } |
| assert(_ioproj_catchall->outcnt() == 0, "all uses must be deleted"); |
| _igvn.remove_dead_node(_ioproj_catchall); |
| } |
| |
| // if we generated only a slow call, we are done |
| if (always_slow) { |
| // 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, ""); |
| // 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 (_fallthroughcatchproj != NULL) { |
| ctrl = _fallthroughcatchproj->clone(); |
| transform_later(ctrl); |
| _igvn.replace_node(_fallthroughcatchproj, result_region); |
| } else { |
| ctrl = top(); |
| } |
| Node *slow_result; |
| if (_resproj == NULL) { |
| // no uses of the allocation result |
| slow_result = top(); |
| } else { |
| slow_result = _resproj->clone(); |
| transform_later(slow_result); |
| _igvn.replace_node(_resproj, result_phi_rawoop); |
| } |
| |
| // Plug slow-path into result merge point |
| result_region ->init_req( slow_result_path, ctrl ); |
| result_phi_rawoop->init_req( slow_result_path, slow_result); |
| result_phi_rawmem->init_req( slow_result_path, _memproj_fallthrough ); |
| transform_later(result_region); |
| transform_later(result_phi_rawoop); |
| transform_later(result_phi_rawmem); |
| transform_later(result_phi_i_o); |
| // This completes all paths into the result merge point |
| } |
| |
| |
| // Helper for PhaseMacroExpand::expand_allocate_common. |
| // Initializes the newly-allocated storage. |
| Node* |
| PhaseMacroExpand::initialize_object(AllocateNode* alloc, |
| Node* control, Node* rawmem, Node* object, |
| Node* klass_node, Node* length, |
| Node* size_in_bytes) { |
| InitializeNode* init = alloc->initialization(); |
| // Store the klass & mark bits |
| Node* mark_node = NULL; |
| // For now only enable fast locking for non-array types |
| if (UseBiasedLocking && (length == NULL)) { |
| mark_node = make_load(control, rawmem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeRawPtr::BOTTOM, T_ADDRESS); |
| } else { |
| mark_node = makecon(TypeRawPtr::make((address)markOopDesc::prototype())); |
| } |
| rawmem = make_store(control, rawmem, object, oopDesc::mark_offset_in_bytes(), mark_node, T_ADDRESS); |
| |
| rawmem = make_store(control, rawmem, object, oopDesc::klass_offset_in_bytes(), klass_node, T_METADATA); |
| int header_size = alloc->minimum_header_size(); // conservatively small |
| |
| // Array length |
| if (length != NULL) { // Arrays need length field |
| rawmem = make_store(control, rawmem, object, arrayOopDesc::length_offset_in_bytes(), length, T_INT); |
| // conservatively small header size: |
| header_size = arrayOopDesc::base_offset_in_bytes(T_BYTE); |
| ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass(); |
| if (k->is_array_klass()) // we know the exact header size in most cases: |
| header_size = Klass::layout_helper_header_size(k->layout_helper()); |
| } |
| |
| // Clear the object body, if necessary. |
| if (init == NULL) { |
| // The init has somehow disappeared; be cautious and clear everything. |
| // |
| // This can happen if a node is allocated but an uncommon trap occurs |
| // immediately. In this case, the Initialize gets associated with the |
| // trap, and may be placed in a different (outer) loop, if the Allocate |
| // is in a loop. If (this is rare) the inner loop gets unrolled, then |
| // there can be two Allocates to one Initialize. The answer in all these |
| // edge cases is safety first. It is always safe to clear immediately |
| // within an Allocate, and then (maybe or maybe not) clear some more later. |
| if (!ZeroTLAB) |
| rawmem = ClearArrayNode::clear_memory(control, rawmem, object, |
| header_size, size_in_bytes, |
| &_igvn); |
| } else { |
| if (!init->is_complete()) { |
| // Try to win by zeroing only what the init does not store. |
| // We can also try to do some peephole optimizations, |
| // such as combining some adjacent subword stores. |
| rawmem = init->complete_stores(control, rawmem, object, |
| header_size, size_in_bytes, &_igvn); |
| } |
| // We have no more use for this link, since the AllocateNode goes away: |
| init->set_req(InitializeNode::RawAddress, top()); |
| // (If we keep the link, it just confuses the register allocator, |
| // who thinks he sees a real use of the address by the membar.) |
| } |
| |
| return rawmem; |
| } |
| |
| // Generate prefetch instructions for next allocations. |
| Node* PhaseMacroExpand::prefetch_allocation(Node* i_o, Node*& needgc_false, |
| Node*& contended_phi_rawmem, |
| Node* old_eden_top, Node* new_eden_top, |
| Node* length) { |
| enum { fall_in_path = 1, pf_path = 2 }; |
| if( UseTLAB && AllocatePrefetchStyle == 2 ) { |
| // Generate prefetch allocation with watermark check. |
| // As an allocation hits the watermark, we will prefetch starting |
| // at a "distance" away from watermark. |
| |
| Node *pf_region = new (C) RegionNode(3); |
| Node *pf_phi_rawmem = new (C) PhiNode( pf_region, Type::MEMORY, |
| TypeRawPtr::BOTTOM ); |
| // I/O is used for Prefetch |
| Node *pf_phi_abio = new (C) PhiNode( pf_region, Type::ABIO ); |
| |
| Node *thread = new (C) ThreadLocalNode(); |
| transform_later(thread); |
| |
| Node *eden_pf_adr = new (C) AddPNode( top()/*not oop*/, thread, |
| _igvn.MakeConX(in_bytes(JavaThread::tlab_pf_top_offset())) ); |
| transform_later(eden_pf_adr); |
| |
| Node *old_pf_wm = new (C) LoadPNode( needgc_false, |
| contended_phi_rawmem, eden_pf_adr, |
| TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM ); |
| transform_later(old_pf_wm); |
| |
| // check against new_eden_top |
| Node *need_pf_cmp = new (C) CmpPNode( new_eden_top, old_pf_wm ); |
| transform_later(need_pf_cmp); |
| Node *need_pf_bol = new (C) BoolNode( need_pf_cmp, BoolTest::ge ); |
| transform_later(need_pf_bol); |
| IfNode *need_pf_iff = new (C) IfNode( needgc_false, need_pf_bol, |
| PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN ); |
| transform_later(need_pf_iff); |
| |
| // true node, add prefetchdistance |
| Node *need_pf_true = new (C) IfTrueNode( need_pf_iff ); |
| transform_later(need_pf_true); |
| |
| Node *need_pf_false = new (C) IfFalseNode( need_pf_iff ); |
| transform_later(need_pf_false); |
| |
| Node *new_pf_wmt = new (C) AddPNode( top(), old_pf_wm, |
| _igvn.MakeConX(AllocatePrefetchDistance) ); |
| transform_later(new_pf_wmt ); |
| new_pf_wmt->set_req(0, need_pf_true); |
| |
| Node *store_new_wmt = new (C) StorePNode( need_pf_true, |
| contended_phi_rawmem, eden_pf_adr, |
| TypeRawPtr::BOTTOM, new_pf_wmt ); |
| transform_later(store_new_wmt); |
| |
| // adding prefetches |
| pf_phi_abio->init_req( fall_in_path, i_o ); |
| |
| Node *prefetch_adr; |
| Node *prefetch; |
| uint lines = AllocatePrefetchDistance / AllocatePrefetchStepSize; |
| uint step_size = AllocatePrefetchStepSize; |
| uint distance = 0; |
| |
| for ( uint i = 0; i < lines; i++ ) { |
| prefetch_adr = new (C) AddPNode( old_pf_wm, new_pf_wmt, |
| _igvn.MakeConX(distance) ); |
| transform_later(prefetch_adr); |
| prefetch = new (C) PrefetchAllocationNode( i_o, prefetch_adr ); |
| transform_later(prefetch); |
| distance += step_size; |
| i_o = prefetch; |
| } |
| pf_phi_abio->set_req( pf_path, i_o ); |
| |
| pf_region->init_req( fall_in_path, need_pf_false ); |
| pf_region->init_req( pf_path, need_pf_true ); |
| |
| pf_phi_rawmem->init_req( fall_in_path, contended_phi_rawmem ); |
| pf_phi_rawmem->init_req( pf_path, store_new_wmt ); |
| |
| transform_later(pf_region); |
| transform_later(pf_phi_rawmem); |
| transform_later(pf_phi_abio); |
| |
| needgc_false = pf_region; |
| contended_phi_rawmem = pf_phi_rawmem; |
| i_o = pf_phi_abio; |
| } else if( UseTLAB && AllocatePrefetchStyle == 3 ) { |
| // Insert a prefetch for each allocation. |
| // This code is used for Sparc with BIS. |
| Node *pf_region = new (C) RegionNode(3); |
| Node *pf_phi_rawmem = new (C) PhiNode( pf_region, Type::MEMORY, |
| TypeRawPtr::BOTTOM ); |
| |
| // Generate several prefetch instructions. |
| uint lines = (length != NULL) ? AllocatePrefetchLines : AllocateInstancePrefetchLines; |
| uint step_size = AllocatePrefetchStepSize; |
| uint distance = AllocatePrefetchDistance; |
| |
| // Next cache address. |
| Node *cache_adr = new (C) AddPNode(old_eden_top, old_eden_top, |
| _igvn.MakeConX(distance)); |
| transform_later(cache_adr); |
| cache_adr = new (C) CastP2XNode(needgc_false, cache_adr); |
| transform_later(cache_adr); |
| Node* mask = _igvn.MakeConX(~(intptr_t)(step_size-1)); |
| cache_adr = new (C) AndXNode(cache_adr, mask); |
| transform_later(cache_adr); |
| cache_adr = new (C) CastX2PNode(cache_adr); |
| transform_later(cache_adr); |
| |
| // Prefetch |
| Node *prefetch = new (C) PrefetchAllocationNode( contended_phi_rawmem, cache_adr ); |
| prefetch->set_req(0, needgc_false); |
| transform_later(prefetch); |
| contended_phi_rawmem = prefetch; |
| Node *prefetch_adr; |
| distance = step_size; |
| for ( uint i = 1; i < lines; i++ ) { |
| prefetch_adr = new (C) AddPNode( cache_adr, cache_adr, |
| _igvn.MakeConX(distance) ); |
| transform_later(prefetch_adr); |
| prefetch = new (C) PrefetchAllocationNode( contended_phi_rawmem, prefetch_adr ); |
| transform_later(prefetch); |
| distance += step_size; |
| contended_phi_rawmem = prefetch; |
| } |
| } else if( AllocatePrefetchStyle > 0 ) { |
| // Insert a prefetch for each allocation only on the fast-path |
| Node *prefetch_adr; |
| Node *prefetch; |
| // Generate several prefetch instructions. |
| uint lines = (length != NULL) ? AllocatePrefetchLines : AllocateInstancePrefetchLines; |
| uint step_size = AllocatePrefetchStepSize; |
| uint distance = AllocatePrefetchDistance; |
| for ( uint i = 0; i < lines; i++ ) { |
| prefetch_adr = new (C) AddPNode( old_eden_top, new_eden_top, |
| _igvn.MakeConX(distance) ); |
| transform_later(prefetch_adr); |
| prefetch = new (C) PrefetchAllocationNode( i_o, prefetch_adr ); |
| // Do not let it float too high, since if eden_top == eden_end, |
| // both might be null. |
| if( i == 0 ) { // Set control for first prefetch, next follows it |
| prefetch->init_req(0, needgc_false); |
| } |
| transform_later(prefetch); |
| distance += step_size; |
| i_o = prefetch; |
| } |
| } |
| return i_o; |
| } |
| |
| |
| void PhaseMacroExpand::expand_allocate(AllocateNode *alloc) { |
| expand_allocate_common(alloc, NULL, |
| OptoRuntime::new_instance_Type(), |
| OptoRuntime::new_instance_Java()); |
| } |
| |
| void PhaseMacroExpand::expand_allocate_array(AllocateArrayNode *alloc) { |
| Node* length = alloc->in(AllocateNode::ALength); |
| InitializeNode* init = alloc->initialization(); |
| Node* klass_node = alloc->in(AllocateNode::KlassNode); |
| ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass(); |
| address slow_call_address; // Address of slow call |
| if (init != NULL && init->is_complete_with_arraycopy() && |
| k->is_type_array_klass()) { |
| // Don't zero type array during slow allocation in VM since |
| // it will be initialized later by arraycopy in compiled code. |
| slow_call_address = OptoRuntime::new_array_nozero_Java(); |
| } else { |
| slow_call_address = OptoRuntime::new_array_Java(); |
| } |
| expand_allocate_common(alloc, length, |
| OptoRuntime::new_array_Type(), |
| slow_call_address); |
| } |
| |
| //-------------------mark_eliminated_box---------------------------------- |
| // |
| // During EA obj may point to several objects but after few ideal graph |
| // transformations (CCP) it may point to only one non escaping object |
| // (but still using phi), corresponding locks and unlocks will be marked |
| // for elimination. Later obj could be replaced with a new node (new phi) |
| // and which does not have escape information. And later after some graph |
| // reshape other locks and unlocks (which were not marked for elimination |
| // before) are connected to this new obj (phi) but they still will not be |
| // marked for elimination since new obj has no escape information. |
| // Mark all associated (same box and obj) lock and unlock nodes for |
| // elimination if some of them marked already. |
| void PhaseMacroExpand::mark_eliminated_box(Node* oldbox, Node* obj) { |
| if (oldbox->as_BoxLock()->is_eliminated()) |
| return; // This BoxLock node was processed already. |
| |
| // New implementation (EliminateNestedLocks) has separate BoxLock |
| // node for each locked region so mark all associated locks/unlocks as |
| // eliminated even if different objects are referenced in one locked region |
| // (for example, OSR compilation of nested loop inside locked scope). |
| if (EliminateNestedLocks || |
| oldbox->as_BoxLock()->is_simple_lock_region(NULL, obj)) { |
| // Box is used only in one lock region. Mark this box as eliminated. |
| _igvn.hash_delete(oldbox); |
| oldbox->as_BoxLock()->set_eliminated(); // This changes box's hash value |
| _igvn.hash_insert(oldbox); |
| |
| for (uint i = 0; i < oldbox->outcnt(); i++) { |
| Node* u = oldbox->raw_out(i); |
| if (u->is_AbstractLock() && !u->as_AbstractLock()->is_non_esc_obj()) { |
| AbstractLockNode* alock = u->as_AbstractLock(); |
| // Check lock's box since box could be referenced by Lock's debug info. |
| if (alock->box_node() == oldbox) { |
| // Mark eliminated all related locks and unlocks. |
| alock->set_non_esc_obj(); |
| } |
| } |
| } |
| return; |
| } |
| |
| // Create new "eliminated" BoxLock node and use it in monitor debug info |
| // instead of oldbox for the same object. |
| BoxLockNode* newbox = oldbox->clone()->as_BoxLock(); |
| |
| // Note: BoxLock node is marked eliminated only here and it is used |
| // to indicate that all associated lock and unlock nodes are marked |
| // for elimination. |
| newbox->set_eliminated(); |
| transform_later(newbox); |
| |
| // Replace old box node with new box for all users of the same object. |
| for (uint i = 0; i < oldbox->outcnt();) { |
| bool next_edge = true; |
| |
| Node* u = oldbox->raw_out(i); |
| if (u->is_AbstractLock()) { |
| AbstractLockNode* alock = u->as_AbstractLock(); |
| if (alock->box_node() == oldbox && alock->obj_node()->eqv_uncast(obj)) { |
| // Replace Box and mark eliminated all related locks and unlocks. |
| alock->set_non_esc_obj(); |
| _igvn.rehash_node_delayed(alock); |
| alock->set_box_node(newbox); |
| next_edge = false; |
| } |
| } |
| if (u->is_FastLock() && u->as_FastLock()->obj_node()->eqv_uncast(obj)) { |
| FastLockNode* flock = u->as_FastLock(); |
| assert(flock->box_node() == oldbox, "sanity"); |
| _igvn.rehash_node_delayed(flock); |
| flock->set_box_node(newbox); |
| next_edge = false; |
| } |
| |
| // Replace old box in monitor debug info. |
| if (u->is_SafePoint() && u->as_SafePoint()->jvms()) { |
| SafePointNode* sfn = u->as_SafePoint(); |
| JVMState* youngest_jvms = sfn->jvms(); |
| int max_depth = youngest_jvms->depth(); |
| for (int depth = 1; depth <= max_depth; depth++) { |
| JVMState* jvms = youngest_jvms->of_depth(depth); |
| int num_mon = jvms->nof_monitors(); |
| // Loop over monitors |
| for (int idx = 0; idx < num_mon; idx++) { |
| Node* obj_node = sfn->monitor_obj(jvms, idx); |
| Node* box_node = sfn->monitor_box(jvms, idx); |
| if (box_node == oldbox && obj_node->eqv_uncast(obj)) { |
| int j = jvms->monitor_box_offset(idx); |
| _igvn.replace_input_of(u, j, newbox); |
| next_edge = false; |
| } |
| } |
| } |
| } |
| if (next_edge) i++; |
| } |
| } |
| |
| //-----------------------mark_eliminated_locking_nodes----------------------- |
| void PhaseMacroExpand::mark_eliminated_locking_nodes(AbstractLockNode *alock) { |
| if (EliminateNestedLocks) { |
| if (alock->is_nested()) { |
| assert(alock->box_node()->as_BoxLock()->is_eliminated(), "sanity"); |
| return; |
| } else if (!alock->is_non_esc_obj()) { // Not eliminated or coarsened |
| // Only Lock node has JVMState needed here. |
| if (alock->jvms() != NULL && alock->as_Lock()->is_nested_lock_region()) { |
| // Mark eliminated related nested locks and unlocks. |
| Node* obj = alock->obj_node(); |
| BoxLockNode* box_node = alock->box_node()->as_BoxLock(); |
| assert(!box_node->is_eliminated(), "should not be marked yet"); |
| // Note: BoxLock node is marked eliminated only here |
| // and it is used to indicate that all associated lock |
| // and unlock nodes are marked for elimination. |
| box_node->set_eliminated(); // Box's hash is always NO_HASH here |
| for (uint i = 0; i < box_node->outcnt(); i++) { |
| Node* u = box_node->raw_out(i); |
| if (u->is_AbstractLock()) { |
| alock = u->as_AbstractLock(); |
| if (alock->box_node() == box_node) { |
| // Verify that this Box is referenced only by related locks. |
| assert(alock->obj_node()->eqv_uncast(obj), ""); |
| // Mark all related locks and unlocks. |
| alock->set_nested(); |
| } |
| } |
| } |
| } |
| return; |
| } |
| // Process locks for non escaping object |
| assert(alock->is_non_esc_obj(), ""); |
| } // EliminateNestedLocks |
| |
| if (alock->is_non_esc_obj()) { // Lock is used for non escaping object |
| // Look for all locks of this object and mark them and |
| // corresponding BoxLock nodes as eliminated. |
| Node* obj = alock->obj_node(); |
| for (uint j = 0; j < obj->outcnt(); j++) { |
| Node* o = obj->raw_out(j); |
| if (o->is_AbstractLock() && |
| o->as_AbstractLock()->obj_node()->eqv_uncast(obj)) { |
| alock = o->as_AbstractLock(); |
| Node* box = alock->box_node(); |
| // Replace old box node with new eliminated box for all users |
| // of the same object and mark related locks as eliminated. |
| mark_eliminated_box(box, obj); |
| } |
| } |
| } |
| } |
| |
| // we have determined that this lock/unlock can be eliminated, we simply |
| // eliminate the node without expanding it. |
| // |
| // Note: The membar's associated with the lock/unlock are currently not |
| // eliminated. This should be investigated as a future enhancement. |
| // |
| bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) { |
| |
| if (!alock->is_eliminated()) { |
| return false; |
| } |
| #ifdef ASSERT |
| if (!alock->is_coarsened()) { |
| // Check that new "eliminated" BoxLock node is created. |
| BoxLockNode* oldbox = alock->box_node()->as_BoxLock(); |
| assert(oldbox->is_eliminated(), "should be done already"); |
| } |
| #endif |
| CompileLog* log = C->log(); |
| if (log != NULL) { |
| log->head("eliminate_lock lock='%d'", |
| alock->is_Lock()); |
| JVMState* p = alock->jvms(); |
| while (p != NULL) { |
| log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method())); |
| p = p->caller(); |
| } |
| log->tail("eliminate_lock"); |
| } |
| |
| #ifndef PRODUCT |
| if (PrintEliminateLocks) { |
| if (alock->is_Lock()) { |
| tty->print_cr("++++ Eliminated: %d Lock", alock->_idx); |
| } else { |
| tty->print_cr("++++ Eliminated: %d Unlock", alock->_idx); |
| } |
| } |
| #endif |
| |
| Node* mem = alock->in(TypeFunc::Memory); |
| Node* ctrl = alock->in(TypeFunc::Control); |
| |
| extract_call_projections(alock); |
| // There are 2 projections from the lock. The lock node will |
| // be deleted when its last use is subsumed below. |
| assert(alock->outcnt() == 2 && |
| _fallthroughproj != NULL && |
| _memproj_fallthrough != NULL, |
| "Unexpected projections from Lock/Unlock"); |
| |
| Node* fallthroughproj = _fallthroughproj; |
| Node* memproj_fallthrough = _memproj_fallthrough; |
| |
| // The memory projection from a lock/unlock is RawMem |
| // The input to a Lock is merged memory, so extract its RawMem input |
| // (unless the MergeMem has been optimized away.) |
| if (alock->is_Lock()) { |
| // Seach for MemBarAcquireLock node and delete it also. |
| MemBarNode* membar = fallthroughproj->unique_ctrl_out()->as_MemBar(); |
| assert(membar != NULL && membar->Opcode() == Op_MemBarAcquireLock, ""); |
| Node* ctrlproj = membar->proj_out(TypeFunc::Control); |
| Node* memproj = membar->proj_out(TypeFunc::Memory); |
| _igvn.replace_node(ctrlproj, fallthroughproj); |
| _igvn.replace_node(memproj, memproj_fallthrough); |
| |
| // Delete FastLock node also if this Lock node is unique user |
| // (a loop peeling may clone a Lock node). |
| Node* flock = alock->as_Lock()->fastlock_node(); |
| if (flock->outcnt() == 1) { |
| assert(flock->unique_out() == alock, "sanity"); |
| _igvn.replace_node(flock, top()); |
| } |
| } |
| |
| // Seach for MemBarReleaseLock node and delete it also. |
| if (alock->is_Unlock() && ctrl != NULL && ctrl->is_Proj() && |
| ctrl->in(0)->is_MemBar()) { |
| MemBarNode* membar = ctrl->in(0)->as_MemBar(); |
| assert(membar->Opcode() == Op_MemBarReleaseLock && |
| mem->is_Proj() && membar == mem->in(0), ""); |
| _igvn.replace_node(fallthroughproj, ctrl); |
| _igvn.replace_node(memproj_fallthrough, mem); |
| fallthroughproj = ctrl; |
| memproj_fallthrough = mem; |
| ctrl = membar->in(TypeFunc::Control); |
| mem = membar->in(TypeFunc::Memory); |
| } |
| |
| _igvn.replace_node(fallthroughproj, ctrl); |
| _igvn.replace_node(memproj_fallthrough, mem); |
| return true; |
| } |
| |
| |
| //------------------------------expand_lock_node---------------------- |
| void PhaseMacroExpand::expand_lock_node(LockNode *lock) { |
| |
| Node* ctrl = lock->in(TypeFunc::Control); |
| Node* mem = lock->in(TypeFunc::Memory); |
| Node* obj = lock->obj_node(); |
| Node* box = lock->box_node(); |
| Node* flock = lock->fastlock_node(); |
| |
| assert(!box->as_BoxLock()->is_eliminated(), "sanity"); |
| |
| // Make the merge point |
| Node *region; |
| Node *mem_phi; |
| Node *slow_path; |
| |
| if (UseOptoBiasInlining) { |
| /* |
| * See the full description in MacroAssembler::biased_locking_enter(). |
| * |
| * if( (mark_word & biased_lock_mask) == biased_lock_pattern ) { |
| * // The object is biased. |
| * proto_node = klass->prototype_header; |
| * o_node = thread | proto_node; |
| * x_node = o_node ^ mark_word; |
| * if( (x_node & ~age_mask) == 0 ) { // Biased to the current thread ? |
| * // Done. |
| * } else { |
| * if( (x_node & biased_lock_mask) != 0 ) { |
| * // The klass's prototype header is no longer biased. |
| * cas(&mark_word, mark_word, proto_node) |
| * goto cas_lock; |
| * } else { |
| * // The klass's prototype header is still biased. |
| * if( (x_node & epoch_mask) != 0 ) { // Expired epoch? |
| * old = mark_word; |
| * new = o_node; |
| * } else { |
| * // Different thread or anonymous biased. |
| * old = mark_word & (epoch_mask | age_mask | biased_lock_mask); |
| * new = thread | old; |
| * } |
| * // Try to rebias. |
| * if( cas(&mark_word, old, new) == 0 ) { |
| * // Done. |
| * } else { |
| * goto slow_path; // Failed. |
| * } |
| * } |
| * } |
| * } else { |
| * // The object is not biased. |
| * cas_lock: |
| * if( FastLock(obj) == 0 ) { |
| * // Done. |
| * } else { |
| * slow_path: |
| * OptoRuntime::complete_monitor_locking_Java(obj); |
| * } |
| * } |
| */ |
| |
| region = new (C) RegionNode(5); |
| // create a Phi for the memory state |
| mem_phi = new (C) PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); |
| |
| Node* fast_lock_region = new (C) RegionNode(3); |
| Node* fast_lock_mem_phi = new (C) PhiNode( fast_lock_region, Type::MEMORY, TypeRawPtr::BOTTOM); |
| |
| // First, check mark word for the biased lock pattern. |
| Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type()); |
| |
| // Get fast path - mark word has the biased lock pattern. |
| ctrl = opt_bits_test(ctrl, fast_lock_region, 1, mark_node, |
| markOopDesc::biased_lock_mask_in_place, |
| markOopDesc::biased_lock_pattern, true); |
| // fast_lock_region->in(1) is set to slow path. |
| fast_lock_mem_phi->init_req(1, mem); |
| |
| // Now check that the lock is biased to the current thread and has |
| // the same epoch and bias as Klass::_prototype_header. |
| |
| // Special-case a fresh allocation to avoid building nodes: |
| Node* klass_node = AllocateNode::Ideal_klass(obj, &_igvn); |
| if (klass_node == NULL) { |
| Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes()); |
| klass_node = transform_later( LoadKlassNode::make(_igvn, mem, k_adr, _igvn.type(k_adr)->is_ptr()) ); |
| #ifdef _LP64 |
| if (UseCompressedClassPointers && klass_node->is_DecodeNKlass()) { |
| assert(klass_node->in(1)->Opcode() == Op_LoadNKlass, "sanity"); |
| klass_node->in(1)->init_req(0, ctrl); |
| } else |
| #endif |
| klass_node->init_req(0, ctrl); |
| } |
| Node *proto_node = make_load(ctrl, mem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeX_X, TypeX_X->basic_type()); |
| |
| Node* thread = transform_later(new (C) ThreadLocalNode()); |
| Node* cast_thread = transform_later(new (C) CastP2XNode(ctrl, thread)); |
| Node* o_node = transform_later(new (C) OrXNode(cast_thread, proto_node)); |
| Node* x_node = transform_later(new (C) XorXNode(o_node, mark_node)); |
| |
| // Get slow path - mark word does NOT match the value. |
| Node* not_biased_ctrl = opt_bits_test(ctrl, region, 3, x_node, |
| (~markOopDesc::age_mask_in_place), 0); |
| // region->in(3) is set to fast path - the object is biased to the current thread. |
| mem_phi->init_req(3, mem); |
| |
| |
| // Mark word does NOT match the value (thread | Klass::_prototype_header). |
| |
| |
| // First, check biased pattern. |
| // Get fast path - _prototype_header has the same biased lock pattern. |
| ctrl = opt_bits_test(not_biased_ctrl, fast_lock_region, 2, x_node, |
| markOopDesc::biased_lock_mask_in_place, 0, true); |
| |
| not_biased_ctrl = fast_lock_region->in(2); // Slow path |
| // fast_lock_region->in(2) - the prototype header is no longer biased |
| // and we have to revoke the bias on this object. |
| // We are going to try to reset the mark of this object to the prototype |
| // value and fall through to the CAS-based locking scheme. |
| Node* adr = basic_plus_adr(obj, oopDesc::mark_offset_in_bytes()); |
| Node* cas = new (C) StoreXConditionalNode(not_biased_ctrl, mem, adr, |
| proto_node, mark_node); |
| transform_later(cas); |
| Node* proj = transform_later( new (C) SCMemProjNode(cas)); |
| fast_lock_mem_phi->init_req(2, proj); |
| |
| |
| // Second, check epoch bits. |
| Node* rebiased_region = new (C) RegionNode(3); |
| Node* old_phi = new (C) PhiNode( rebiased_region, TypeX_X); |
| Node* new_phi = new (C) PhiNode( rebiased_region, TypeX_X); |
| |
| // Get slow path - mark word does NOT match epoch bits. |
| Node* epoch_ctrl = opt_bits_test(ctrl, rebiased_region, 1, x_node, |
| markOopDesc::epoch_mask_in_place, 0); |
| // The epoch of the current bias is not valid, attempt to rebias the object |
| // toward the current thread. |
| rebiased_region->init_req(2, epoch_ctrl); |
| old_phi->init_req(2, mark_node); |
| new_phi->init_req(2, o_node); |
| |
| // rebiased_region->in(1) is set to fast path. |
| // The epoch of the current bias is still valid but we know |
| // nothing about the owner; it might be set or it might be clear. |
| Node* cmask = MakeConX(markOopDesc::biased_lock_mask_in_place | |
| markOopDesc::age_mask_in_place | |
| markOopDesc::epoch_mask_in_place); |
| Node* old = transform_later(new (C) AndXNode(mark_node, cmask)); |
| cast_thread = transform_later(new (C) CastP2XNode(ctrl, thread)); |
| Node* new_mark = transform_later(new (C) OrXNode(cast_thread, old)); |
| old_phi->init_req(1, old); |
| new_phi->init_req(1, new_mark); |
| |
| transform_later(rebiased_region); |
| transform_later(old_phi); |
| transform_later(new_phi); |
| |
| // Try to acquire the bias of the object using an atomic operation. |
| // If this fails we will go in to the runtime to revoke the object's bias. |
| cas = new (C) StoreXConditionalNode(rebiased_region, mem, adr, |
| new_phi, old_phi); |
| transform_later(cas); |
| proj = transform_later( new (C) SCMemProjNode(cas)); |
| |
| // Get slow path - Failed to CAS. |
| not_biased_ctrl = opt_bits_test(rebiased_region, region, 4, cas, 0, 0); |
| mem_phi->init_req(4, proj); |
| // region->in(4) is set to fast path - the object is rebiased to the current thread. |
| |
| // Failed to CAS. |
| slow_path = new (C) RegionNode(3); |
| Node *slow_mem = new (C) PhiNode( slow_path, Type::MEMORY, TypeRawPtr::BOTTOM); |
| |
| slow_path->init_req(1, not_biased_ctrl); // Capture slow-control |
| slow_mem->init_req(1, proj); |
| |
| // Call CAS-based locking scheme (FastLock node). |
| |
| transform_later(fast_lock_region); |
| transform_later(fast_lock_mem_phi); |
| |
| // Get slow path - FastLock failed to lock the object. |
| ctrl = opt_bits_test(fast_lock_region, region, 2, flock, 0, 0); |
| mem_phi->init_req(2, fast_lock_mem_phi); |
| // region->in(2) is set to fast path - the object is locked to the current thread. |
| |
| slow_path->init_req(2, ctrl); // Capture slow-control |
| slow_mem->init_req(2, fast_lock_mem_phi); |
| |
| transform_later(slow_path); |
| transform_later(slow_mem); |
| // Reset lock's memory edge. |
| lock->set_req(TypeFunc::Memory, slow_mem); |
| |
| } else { |
| region = new (C) RegionNode(3); |
| // create a Phi for the memory state |
| mem_phi = new (C) PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); |
| |
| // Optimize test; set region slot 2 |
| slow_path = opt_bits_test(ctrl, region, 2, flock, 0, 0); |
| mem_phi->init_req(2, mem); |
| } |
| |
| // Make slow path call |
| CallNode *call = make_slow_call( (CallNode *) lock, OptoRuntime::complete_monitor_enter_Type(), OptoRuntime::complete_monitor_locking_Java(), NULL, slow_path, obj, box ); |
| |
| extract_call_projections(call); |
| |
| // Slow path can only throw asynchronous exceptions, which are always |
| // de-opted. So the compiler thinks the slow-call can never throw an |
| // exception. If it DOES throw an exception we would need the debug |
| // info removed first (since if it throws there is no monitor). |
| assert ( _ioproj_fallthrough == NULL && _ioproj_catchall == NULL && |
| _memproj_catchall == NULL && _catchallcatchproj == NULL, "Unexpected projection from Lock"); |
| |
| // Capture slow path |
| // disconnect fall-through projection from call and create a new one |
| // hook up users of fall-through projection to region |
| Node *slow_ctrl = _fallthroughproj->clone(); |
| transform_later(slow_ctrl); |
| _igvn.hash_delete(_fallthroughproj); |
| _fallthroughproj->disconnect_inputs(NULL, C); |
| region->init_req(1, slow_ctrl); |
| // region inputs are now complete |
| transform_later(region); |
| _igvn.replace_node(_fallthroughproj, region); |
| |
| Node *memproj = transform_later( new(C) ProjNode(call, TypeFunc::Memory) ); |
| mem_phi->init_req(1, memproj ); |
| transform_later(mem_phi); |
| _igvn.replace_node(_memproj_fallthrough, mem_phi); |
| } |
| |
| //------------------------------expand_unlock_node---------------------- |
| void PhaseMacroExpand::expand_unlock_node(UnlockNode *unlock) { |
| |
| Node* ctrl = unlock->in(TypeFunc::Control); |
| Node* mem = unlock->in(TypeFunc::Memory); |
| Node* obj = unlock->obj_node(); |
| Node* box = unlock->box_node(); |
| |
| assert(!box->as_BoxLock()->is_eliminated(), "sanity"); |
| |
| // No need for a null check on unlock |
| |
| // Make the merge point |
| Node *region; |
| Node *mem_phi; |
| |
| if (UseOptoBiasInlining) { |
| // Check for biased locking unlock case, which is a no-op. |
| // See the full description in MacroAssembler::biased_locking_exit(). |
| region = new (C) RegionNode(4); |
| // create a Phi for the memory state |
| mem_phi = new (C) PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); |
| mem_phi->init_req(3, mem); |
| |
| Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type()); |
| ctrl = opt_bits_test(ctrl, region, 3, mark_node, |
| markOopDesc::biased_lock_mask_in_place, |
| markOopDesc::biased_lock_pattern); |
| } else { |
| region = new (C) RegionNode(3); |
| // create a Phi for the memory state |
| mem_phi = new (C) PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM); |
| } |
| |
| FastUnlockNode *funlock = new (C) FastUnlockNode( ctrl, obj, box ); |
| funlock = transform_later( funlock )->as_FastUnlock(); |
| // Optimize test; set region slot 2 |
| Node *slow_path = opt_bits_test(ctrl, region, 2, funlock, 0, 0); |
| |
| CallNode *call = make_slow_call( (CallNode *) unlock, OptoRuntime::complete_monitor_exit_Type(), CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C), "complete_monitor_unlocking_C", slow_path, obj, box ); |
| |
| extract_call_projections(call); |
| |
| assert ( _ioproj_fallthrough == NULL && _ioproj_catchall == NULL && |
| _memproj_catchall == NULL && _catchallcatchproj == NULL, "Unexpected projection from Lock"); |
| |
| // No exceptions for unlocking |
| // Capture slow path |
| // disconnect fall-through projection from call and create a new one |
| // hook up users of fall-through projection to region |
| Node *slow_ctrl = _fallthroughproj->clone(); |
| transform_later(slow_ctrl); |
| _igvn.hash_delete(_fallthroughproj); |
| _fallthroughproj->disconnect_inputs(NULL, C); |
| region->init_req(1, slow_ctrl); |
| // region inputs are now complete |
| transform_later(region); |
| _igvn.replace_node(_fallthroughproj, region); |
| |
| Node *memproj = transform_later( new(C) ProjNode(call, TypeFunc::Memory) ); |
| mem_phi->init_req(1, memproj ); |
| mem_phi->init_req(2, mem); |
| transform_later(mem_phi); |
| _igvn.replace_node(_memproj_fallthrough, mem_phi); |
| } |
| |
| //---------------------------eliminate_macro_nodes---------------------- |
| // Eliminate scalar replaced allocations and associated locks. |
| void PhaseMacroExpand::eliminate_macro_nodes() { |
| if (C->macro_count() == 0) |
| return; |
| |
| // First, attempt to eliminate locks |
| int cnt = C->macro_count(); |
| for (int i=0; i < cnt; i++) { |
| Node *n = C->macro_node(i); |
| if (n->is_AbstractLock()) { // Lock and Unlock nodes |
| // Before elimination mark all associated (same box and obj) |
| // lock and unlock nodes. |
| mark_eliminated_locking_nodes(n->as_AbstractLock()); |
| } |
| } |
| bool progress = true; |
| while (progress) { |
| progress = false; |
| for (int i = C->macro_count(); i > 0; i--) { |
| Node * n = C->macro_node(i-1); |
| bool success = false; |
| debug_only(int old_macro_count = C->macro_count();); |
| if (n->is_AbstractLock()) { |
| success = eliminate_locking_node(n->as_AbstractLock()); |
| } |
| assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count"); |
| progress = progress || success; |
| } |
| } |
| // Next, attempt to eliminate allocations |
| progress = true; |
| while (progress) { |
| progress = false; |
| for (int i = C->macro_count(); i > 0; i--) { |
| Node * n = C->macro_node(i-1); |
| bool success = false; |
| debug_only(int old_macro_count = C->macro_count();); |
| switch (n->class_id()) { |
| case Node::Class_Allocate: |
| case Node::Class_AllocateArray: |
| success = eliminate_allocate_node(n->as_Allocate()); |
| break; |
| case Node::Class_CallStaticJava: |
| success = eliminate_boxing_node(n->as_CallStaticJava()); |
| break; |
| case Node::Class_Lock: |
| case Node::Class_Unlock: |
| assert(!n->as_AbstractLock()->is_eliminated(), "sanity"); |
| break; |
| default: |
| assert(n->Opcode() == Op_LoopLimit || |
| n->Opcode() == Op_Opaque1 || |
| n->Opcode() == Op_Opaque2, "unknown node type in macro list"); |
| } |
| assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count"); |
| progress = progress || success; |
| } |
| } |
| } |
| |
| //------------------------------expand_macro_nodes---------------------- |
| // Returns true if a failure occurred. |
| bool PhaseMacroExpand::expand_macro_nodes() { |
| // Last attempt to eliminate macro nodes. |
| eliminate_macro_nodes(); |
| |
| // Make sure expansion will not cause node limit to be exceeded. |
| // Worst case is a macro node gets expanded into about 50 nodes. |
| // Allow 50% more for optimization. |
| if (C->check_node_count(C->macro_count() * 75, "out of nodes before macro expansion" ) ) |
| return true; |
| |
| // Eliminate Opaque and LoopLimit nodes. Do it after all loop optimizations. |
| bool progress = true; |
| while (progress) { |
| progress = false; |
| for (int i = C->macro_count(); i > 0; i--) { |
| Node * n = C->macro_node(i-1); |
| bool success = false; |
| debug_only(int old_macro_count = C->macro_count();); |
| if (n->Opcode() == Op_LoopLimit) { |
| // Remove it from macro list and put on IGVN worklist to optimize. |
| C->remove_macro_node(n); |
| _igvn._worklist.push(n); |
| success = true; |
| } else if (n->Opcode() == Op_CallStaticJava) { |
| // Remove it from macro list and put on IGVN worklist to optimize. |
| C->remove_macro_node(n); |
| _igvn._worklist.push(n); |
| success = true; |
| } else if (n->Opcode() == Op_Opaque1 || n->Opcode() == Op_Opaque2) { |
| _igvn.replace_node(n, n->in(1)); |
| success = true; |
| } |
| assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count"); |
| progress = progress || success; |
| } |
| } |
| |
| // expand "macro" nodes |
| // nodes are removed from the macro list as they are processed |
| while (C->macro_count() > 0) { |
| int macro_count = C->macro_count(); |
| Node * n = C->macro_node(macro_count-1); |
| assert(n->is_macro(), "only macro nodes expected here"); |
| if (_igvn.type(n) == Type::TOP || n->in(0)->is_top() ) { |
| // node is unreachable, so don't try to expand it |
| C->remove_macro_node(n); |
| continue; |
| } |
| switch (n->class_id()) { |
| case Node::Class_Allocate: |
| expand_allocate(n->as_Allocate()); |
| break; |
| case Node::Class_AllocateArray: |
| expand_allocate_array(n->as_AllocateArray()); |
| break; |
| case Node::Class_Lock: |
| expand_lock_node(n->as_Lock()); |
| break; |
| case Node::Class_Unlock: |
| expand_unlock_node(n->as_Unlock()); |
| break; |
| default: |
| assert(false, "unknown node type in macro list"); |
| } |
| assert(C->macro_count() < macro_count, "must have deleted a node from macro list"); |
| if (C->failing()) return true; |
| } |
| |
| _igvn.set_delay_transform(false); |
| _igvn.optimize(); |
| if (C->failing()) return true; |
| return false; |
| } |