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PojavLauncherTeam
GitHub Repository: PojavLauncherTeam/openjdk-multiarch-jdk8u
Path: blob/aarch64-shenandoah-jdk8u272-b10/hotspot/src/share/vm/opto/graphKit.cpp
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/*
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* Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*
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*/
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#include "precompiled.hpp"
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#include "compiler/compileLog.hpp"
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#include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
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#include "gc_implementation/g1/heapRegion.hpp"
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#include "gc_interface/collectedHeap.hpp"
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#include "gc_implementation/shenandoah/shenandoahHeap.hpp"
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#include "memory/barrierSet.hpp"
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#include "memory/cardTableModRefBS.hpp"
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#include "opto/addnode.hpp"
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#include "opto/graphKit.hpp"
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#include "opto/idealKit.hpp"
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#include "opto/locknode.hpp"
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#include "opto/machnode.hpp"
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#include "opto/parse.hpp"
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#include "opto/rootnode.hpp"
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#include "opto/runtime.hpp"
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#include "runtime/deoptimization.hpp"
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#include "runtime/sharedRuntime.hpp"
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#if INCLUDE_ALL_GCS
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#include "gc_implementation/shenandoah/c2/shenandoahBarrierSetC2.hpp"
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#include "gc_implementation/shenandoah/c2/shenandoahSupport.hpp"
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#endif
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//----------------------------GraphKit-----------------------------------------
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// Main utility constructor.
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GraphKit::GraphKit(JVMState* jvms)
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: Phase(Phase::Parser),
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_env(C->env()),
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_gvn(*C->initial_gvn())
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{
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_exceptions = jvms->map()->next_exception();
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if (_exceptions != NULL) jvms->map()->set_next_exception(NULL);
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set_jvms(jvms);
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}
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// Private constructor for parser.
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GraphKit::GraphKit()
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: Phase(Phase::Parser),
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_env(C->env()),
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_gvn(*C->initial_gvn())
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{
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_exceptions = NULL;
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set_map(NULL);
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debug_only(_sp = -99);
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debug_only(set_bci(-99));
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}
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//---------------------------clean_stack---------------------------------------
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// Clear away rubbish from the stack area of the JVM state.
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// This destroys any arguments that may be waiting on the stack.
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void GraphKit::clean_stack(int from_sp) {
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SafePointNode* map = this->map();
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JVMState* jvms = this->jvms();
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int stk_size = jvms->stk_size();
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int stkoff = jvms->stkoff();
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Node* top = this->top();
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for (int i = from_sp; i < stk_size; i++) {
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if (map->in(stkoff + i) != top) {
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map->set_req(stkoff + i, top);
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}
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}
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}
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//--------------------------------sync_jvms-----------------------------------
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// Make sure our current jvms agrees with our parse state.
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JVMState* GraphKit::sync_jvms() const {
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JVMState* jvms = this->jvms();
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jvms->set_bci(bci()); // Record the new bci in the JVMState
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jvms->set_sp(sp()); // Record the new sp in the JVMState
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assert(jvms_in_sync(), "jvms is now in sync");
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return jvms;
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}
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//--------------------------------sync_jvms_for_reexecute---------------------
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// Make sure our current jvms agrees with our parse state. This version
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// uses the reexecute_sp for reexecuting bytecodes.
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JVMState* GraphKit::sync_jvms_for_reexecute() {
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JVMState* jvms = this->jvms();
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jvms->set_bci(bci()); // Record the new bci in the JVMState
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jvms->set_sp(reexecute_sp()); // Record the new sp in the JVMState
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return jvms;
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}
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#ifdef ASSERT
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bool GraphKit::jvms_in_sync() const {
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Parse* parse = is_Parse();
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if (parse == NULL) {
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if (bci() != jvms()->bci()) return false;
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if (sp() != (int)jvms()->sp()) return false;
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return true;
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}
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if (jvms()->method() != parse->method()) return false;
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if (jvms()->bci() != parse->bci()) return false;
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int jvms_sp = jvms()->sp();
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if (jvms_sp != parse->sp()) return false;
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int jvms_depth = jvms()->depth();
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if (jvms_depth != parse->depth()) return false;
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return true;
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}
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// Local helper checks for special internal merge points
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// used to accumulate and merge exception states.
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// They are marked by the region's in(0) edge being the map itself.
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// Such merge points must never "escape" into the parser at large,
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// until they have been handed to gvn.transform.
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static bool is_hidden_merge(Node* reg) {
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if (reg == NULL) return false;
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if (reg->is_Phi()) {
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reg = reg->in(0);
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if (reg == NULL) return false;
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}
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return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
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}
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void GraphKit::verify_map() const {
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if (map() == NULL) return; // null map is OK
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assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
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assert(!map()->has_exceptions(), "call add_exception_states_from 1st");
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assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
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}
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void GraphKit::verify_exception_state(SafePointNode* ex_map) {
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assert(ex_map->next_exception() == NULL, "not already part of a chain");
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assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
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}
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#endif
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//---------------------------stop_and_kill_map---------------------------------
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// Set _map to NULL, signalling a stop to further bytecode execution.
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// First smash the current map's control to a constant, to mark it dead.
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void GraphKit::stop_and_kill_map() {
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SafePointNode* dead_map = stop();
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if (dead_map != NULL) {
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dead_map->disconnect_inputs(NULL, C); // Mark the map as killed.
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assert(dead_map->is_killed(), "must be so marked");
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}
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}
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//--------------------------------stopped--------------------------------------
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// Tell if _map is NULL, or control is top.
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bool GraphKit::stopped() {
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if (map() == NULL) return true;
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else if (control() == top()) return true;
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else return false;
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}
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//-----------------------------has_ex_handler----------------------------------
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// Tell if this method or any caller method has exception handlers.
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bool GraphKit::has_ex_handler() {
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for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
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if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
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return true;
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}
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}
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return false;
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}
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//------------------------------save_ex_oop------------------------------------
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// Save an exception without blowing stack contents or other JVM state.
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void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
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assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
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ex_map->add_req(ex_oop);
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debug_only(verify_exception_state(ex_map));
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}
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inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
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assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
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Node* ex_oop = ex_map->in(ex_map->req()-1);
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if (clear_it) ex_map->del_req(ex_map->req()-1);
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return ex_oop;
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}
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//-----------------------------saved_ex_oop------------------------------------
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// Recover a saved exception from its map.
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Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
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return common_saved_ex_oop(ex_map, false);
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}
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//--------------------------clear_saved_ex_oop---------------------------------
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// Erase a previously saved exception from its map.
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Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
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return common_saved_ex_oop(ex_map, true);
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}
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#ifdef ASSERT
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//---------------------------has_saved_ex_oop----------------------------------
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// Erase a previously saved exception from its map.
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bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
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return ex_map->req() == ex_map->jvms()->endoff()+1;
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}
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#endif
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//-------------------------make_exception_state--------------------------------
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// Turn the current JVM state into an exception state, appending the ex_oop.
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SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
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sync_jvms();
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SafePointNode* ex_map = stop(); // do not manipulate this map any more
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set_saved_ex_oop(ex_map, ex_oop);
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return ex_map;
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}
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//--------------------------add_exception_state--------------------------------
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// Add an exception to my list of exceptions.
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void GraphKit::add_exception_state(SafePointNode* ex_map) {
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if (ex_map == NULL || ex_map->control() == top()) {
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return;
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}
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#ifdef ASSERT
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verify_exception_state(ex_map);
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if (has_exceptions()) {
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assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
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}
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#endif
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// If there is already an exception of exactly this type, merge with it.
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// In particular, null-checks and other low-level exceptions common up here.
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Node* ex_oop = saved_ex_oop(ex_map);
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const Type* ex_type = _gvn.type(ex_oop);
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if (ex_oop == top()) {
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// No action needed.
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return;
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}
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assert(ex_type->isa_instptr(), "exception must be an instance");
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for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
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const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
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// We check sp also because call bytecodes can generate exceptions
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// both before and after arguments are popped!
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if (ex_type2 == ex_type
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&& e2->_jvms->sp() == ex_map->_jvms->sp()) {
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combine_exception_states(ex_map, e2);
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return;
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}
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}
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// No pre-existing exception of the same type. Chain it on the list.
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push_exception_state(ex_map);
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}
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//-----------------------add_exception_states_from-----------------------------
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void GraphKit::add_exception_states_from(JVMState* jvms) {
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SafePointNode* ex_map = jvms->map()->next_exception();
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if (ex_map != NULL) {
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jvms->map()->set_next_exception(NULL);
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for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
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next_map = ex_map->next_exception();
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ex_map->set_next_exception(NULL);
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add_exception_state(ex_map);
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}
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}
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}
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//-----------------------transfer_exceptions_into_jvms-------------------------
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JVMState* GraphKit::transfer_exceptions_into_jvms() {
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if (map() == NULL) {
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// We need a JVMS to carry the exceptions, but the map has gone away.
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// Create a scratch JVMS, cloned from any of the exception states...
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if (has_exceptions()) {
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_map = _exceptions;
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_map = clone_map();
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_map->set_next_exception(NULL);
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clear_saved_ex_oop(_map);
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debug_only(verify_map());
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} else {
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// ...or created from scratch
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JVMState* jvms = new (C) JVMState(_method, NULL);
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jvms->set_bci(_bci);
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jvms->set_sp(_sp);
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jvms->set_map(new (C) SafePointNode(TypeFunc::Parms, jvms));
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set_jvms(jvms);
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for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top());
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set_all_memory(top());
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while (map()->req() < jvms->endoff()) map()->add_req(top());
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}
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// (This is a kludge, in case you didn't notice.)
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set_control(top());
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}
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JVMState* jvms = sync_jvms();
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assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
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jvms->map()->set_next_exception(_exceptions);
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_exceptions = NULL; // done with this set of exceptions
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return jvms;
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}
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static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
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assert(is_hidden_merge(dstphi), "must be a special merge node");
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assert(is_hidden_merge(srcphi), "must be a special merge node");
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uint limit = srcphi->req();
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for (uint i = PhiNode::Input; i < limit; i++) {
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dstphi->add_req(srcphi->in(i));
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}
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}
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static inline void add_one_req(Node* dstphi, Node* src) {
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assert(is_hidden_merge(dstphi), "must be a special merge node");
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assert(!is_hidden_merge(src), "must not be a special merge node");
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dstphi->add_req(src);
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}
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//-----------------------combine_exception_states------------------------------
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// This helper function combines exception states by building phis on a
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// specially marked state-merging region. These regions and phis are
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// untransformed, and can build up gradually. The region is marked by
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// having a control input of its exception map, rather than NULL. Such
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// regions do not appear except in this function, and in use_exception_state.
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void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
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if (failing()) return; // dying anyway...
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JVMState* ex_jvms = ex_map->_jvms;
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assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
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assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
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assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
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assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
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assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
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assert(ex_map->req() == phi_map->req(), "matching maps");
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uint tos = ex_jvms->stkoff() + ex_jvms->sp();
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Node* hidden_merge_mark = root();
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Node* region = phi_map->control();
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MergeMemNode* phi_mem = phi_map->merged_memory();
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MergeMemNode* ex_mem = ex_map->merged_memory();
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if (region->in(0) != hidden_merge_mark) {
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// The control input is not (yet) a specially-marked region in phi_map.
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// Make it so, and build some phis.
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region = new (C) RegionNode(2);
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_gvn.set_type(region, Type::CONTROL);
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region->set_req(0, hidden_merge_mark); // marks an internal ex-state
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region->init_req(1, phi_map->control());
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phi_map->set_control(region);
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Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
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record_for_igvn(io_phi);
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_gvn.set_type(io_phi, Type::ABIO);
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phi_map->set_i_o(io_phi);
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for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
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Node* m = mms.memory();
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Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
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record_for_igvn(m_phi);
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_gvn.set_type(m_phi, Type::MEMORY);
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mms.set_memory(m_phi);
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}
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}
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// Either or both of phi_map and ex_map might already be converted into phis.
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Node* ex_control = ex_map->control();
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// if there is special marking on ex_map also, we add multiple edges from src
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bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
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// how wide was the destination phi_map, originally?
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uint orig_width = region->req();
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if (add_multiple) {
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add_n_reqs(region, ex_control);
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add_n_reqs(phi_map->i_o(), ex_map->i_o());
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} else {
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// ex_map has no merges, so we just add single edges everywhere
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add_one_req(region, ex_control);
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add_one_req(phi_map->i_o(), ex_map->i_o());
384
}
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for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
386
if (mms.is_empty()) {
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// get a copy of the base memory, and patch some inputs into it
388
const TypePtr* adr_type = mms.adr_type(C);
389
Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
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assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
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mms.set_memory(phi);
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// Prepare to append interesting stuff onto the newly sliced phi:
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while (phi->req() > orig_width) phi->del_req(phi->req()-1);
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}
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// Append stuff from ex_map:
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if (add_multiple) {
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add_n_reqs(mms.memory(), mms.memory2());
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} else {
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add_one_req(mms.memory(), mms.memory2());
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}
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}
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uint limit = ex_map->req();
403
for (uint i = TypeFunc::Parms; i < limit; i++) {
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// Skip everything in the JVMS after tos. (The ex_oop follows.)
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if (i == tos) i = ex_jvms->monoff();
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Node* src = ex_map->in(i);
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Node* dst = phi_map->in(i);
408
if (src != dst) {
409
PhiNode* phi;
410
if (dst->in(0) != region) {
411
dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
412
record_for_igvn(phi);
413
_gvn.set_type(phi, phi->type());
414
phi_map->set_req(i, dst);
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// Prepare to append interesting stuff onto the new phi:
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while (dst->req() > orig_width) dst->del_req(dst->req()-1);
417
} else {
418
assert(dst->is_Phi(), "nobody else uses a hidden region");
419
phi = dst->as_Phi();
420
}
421
if (add_multiple && src->in(0) == ex_control) {
422
// Both are phis.
423
add_n_reqs(dst, src);
424
} else {
425
while (dst->req() < region->req()) add_one_req(dst, src);
426
}
427
const Type* srctype = _gvn.type(src);
428
if (phi->type() != srctype) {
429
const Type* dsttype = phi->type()->meet_speculative(srctype);
430
if (phi->type() != dsttype) {
431
phi->set_type(dsttype);
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_gvn.set_type(phi, dsttype);
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}
434
}
435
}
436
}
437
phi_map->merge_replaced_nodes_with(ex_map);
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}
439
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//--------------------------use_exception_state--------------------------------
441
Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
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if (failing()) { stop(); return top(); }
443
Node* region = phi_map->control();
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Node* hidden_merge_mark = root();
445
assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
446
Node* ex_oop = clear_saved_ex_oop(phi_map);
447
if (region->in(0) == hidden_merge_mark) {
448
// Special marking for internal ex-states. Process the phis now.
449
region->set_req(0, region); // now it's an ordinary region
450
set_jvms(phi_map->jvms()); // ...so now we can use it as a map
451
// Note: Setting the jvms also sets the bci and sp.
452
set_control(_gvn.transform(region));
453
uint tos = jvms()->stkoff() + sp();
454
for (uint i = 1; i < tos; i++) {
455
Node* x = phi_map->in(i);
456
if (x->in(0) == region) {
457
assert(x->is_Phi(), "expected a special phi");
458
phi_map->set_req(i, _gvn.transform(x));
459
}
460
}
461
for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
462
Node* x = mms.memory();
463
if (x->in(0) == region) {
464
assert(x->is_Phi(), "nobody else uses a hidden region");
465
mms.set_memory(_gvn.transform(x));
466
}
467
}
468
if (ex_oop->in(0) == region) {
469
assert(ex_oop->is_Phi(), "expected a special phi");
470
ex_oop = _gvn.transform(ex_oop);
471
}
472
} else {
473
set_jvms(phi_map->jvms());
474
}
475
476
assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
477
assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
478
return ex_oop;
479
}
480
481
//---------------------------------java_bc-------------------------------------
482
Bytecodes::Code GraphKit::java_bc() const {
483
ciMethod* method = this->method();
484
int bci = this->bci();
485
if (method != NULL && bci != InvocationEntryBci)
486
return method->java_code_at_bci(bci);
487
else
488
return Bytecodes::_illegal;
489
}
490
491
void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
492
bool must_throw) {
493
// if the exception capability is set, then we will generate code
494
// to check the JavaThread.should_post_on_exceptions flag to see
495
// if we actually need to report exception events (for this
496
// thread). If we don't need to report exception events, we will
497
// take the normal fast path provided by add_exception_events. If
498
// exception event reporting is enabled for this thread, we will
499
// take the uncommon_trap in the BuildCutout below.
500
501
// first must access the should_post_on_exceptions_flag in this thread's JavaThread
502
Node* jthread = _gvn.transform(new (C) ThreadLocalNode());
503
Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
504
Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered);
505
506
// Test the should_post_on_exceptions_flag vs. 0
507
Node* chk = _gvn.transform( new (C) CmpINode(should_post_flag, intcon(0)) );
508
Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
509
510
// Branch to slow_path if should_post_on_exceptions_flag was true
511
{ BuildCutout unless(this, tst, PROB_MAX);
512
// Do not try anything fancy if we're notifying the VM on every throw.
513
// Cf. case Bytecodes::_athrow in parse2.cpp.
514
uncommon_trap(reason, Deoptimization::Action_none,
515
(ciKlass*)NULL, (char*)NULL, must_throw);
516
}
517
518
}
519
520
//------------------------------builtin_throw----------------------------------
521
void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
522
bool must_throw = true;
523
524
if (env()->jvmti_can_post_on_exceptions()) {
525
// check if we must post exception events, take uncommon trap if so
526
uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
527
// here if should_post_on_exceptions is false
528
// continue on with the normal codegen
529
}
530
531
// If this particular condition has not yet happened at this
532
// bytecode, then use the uncommon trap mechanism, and allow for
533
// a future recompilation if several traps occur here.
534
// If the throw is hot, try to use a more complicated inline mechanism
535
// which keeps execution inside the compiled code.
536
bool treat_throw_as_hot = false;
537
ciMethodData* md = method()->method_data();
538
539
if (ProfileTraps) {
540
if (too_many_traps(reason)) {
541
treat_throw_as_hot = true;
542
}
543
// (If there is no MDO at all, assume it is early in
544
// execution, and that any deopts are part of the
545
// startup transient, and don't need to be remembered.)
546
547
// Also, if there is a local exception handler, treat all throws
548
// as hot if there has been at least one in this method.
549
if (C->trap_count(reason) != 0
550
&& method()->method_data()->trap_count(reason) != 0
551
&& has_ex_handler()) {
552
treat_throw_as_hot = true;
553
}
554
}
555
556
// If this throw happens frequently, an uncommon trap might cause
557
// a performance pothole. If there is a local exception handler,
558
// and if this particular bytecode appears to be deoptimizing often,
559
// let us handle the throw inline, with a preconstructed instance.
560
// Note: If the deopt count has blown up, the uncommon trap
561
// runtime is going to flush this nmethod, not matter what.
562
if (treat_throw_as_hot
563
&& (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
564
// If the throw is local, we use a pre-existing instance and
565
// punt on the backtrace. This would lead to a missing backtrace
566
// (a repeat of 4292742) if the backtrace object is ever asked
567
// for its backtrace.
568
// Fixing this remaining case of 4292742 requires some flavor of
569
// escape analysis. Leave that for the future.
570
ciInstance* ex_obj = NULL;
571
switch (reason) {
572
case Deoptimization::Reason_null_check:
573
ex_obj = env()->NullPointerException_instance();
574
break;
575
case Deoptimization::Reason_div0_check:
576
ex_obj = env()->ArithmeticException_instance();
577
break;
578
case Deoptimization::Reason_range_check:
579
ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
580
break;
581
case Deoptimization::Reason_class_check:
582
if (java_bc() == Bytecodes::_aastore) {
583
ex_obj = env()->ArrayStoreException_instance();
584
} else {
585
ex_obj = env()->ClassCastException_instance();
586
}
587
break;
588
}
589
if (failing()) { stop(); return; } // exception allocation might fail
590
if (ex_obj != NULL) {
591
// Cheat with a preallocated exception object.
592
if (C->log() != NULL)
593
C->log()->elem("hot_throw preallocated='1' reason='%s'",
594
Deoptimization::trap_reason_name(reason));
595
const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj);
596
Node* ex_node = _gvn.transform( ConNode::make(C, ex_con) );
597
598
// Clear the detail message of the preallocated exception object.
599
// Weblogic sometimes mutates the detail message of exceptions
600
// using reflection.
601
int offset = java_lang_Throwable::get_detailMessage_offset();
602
const TypePtr* adr_typ = ex_con->add_offset(offset);
603
604
Node *adr = basic_plus_adr(ex_node, ex_node, offset);
605
const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
606
// Conservatively release stores of object references.
607
Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, MemNode::release);
608
609
add_exception_state(make_exception_state(ex_node));
610
return;
611
}
612
}
613
614
// %%% Maybe add entry to OptoRuntime which directly throws the exc.?
615
// It won't be much cheaper than bailing to the interp., since we'll
616
// have to pass up all the debug-info, and the runtime will have to
617
// create the stack trace.
618
619
// Usual case: Bail to interpreter.
620
// Reserve the right to recompile if we haven't seen anything yet.
621
622
assert(!Deoptimization::reason_is_speculate(reason), "unsupported");
623
Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
624
if (treat_throw_as_hot
625
&& (method()->method_data()->trap_recompiled_at(bci(), NULL)
626
|| C->too_many_traps(reason))) {
627
// We cannot afford to take more traps here. Suffer in the interpreter.
628
if (C->log() != NULL)
629
C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
630
Deoptimization::trap_reason_name(reason),
631
C->trap_count(reason));
632
action = Deoptimization::Action_none;
633
}
634
635
// "must_throw" prunes the JVM state to include only the stack, if there
636
// are no local exception handlers. This should cut down on register
637
// allocation time and code size, by drastically reducing the number
638
// of in-edges on the call to the uncommon trap.
639
640
uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
641
}
642
643
644
//----------------------------PreserveJVMState---------------------------------
645
PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
646
debug_only(kit->verify_map());
647
_kit = kit;
648
_map = kit->map(); // preserve the map
649
_sp = kit->sp();
650
kit->set_map(clone_map ? kit->clone_map() : NULL);
651
#ifdef ASSERT
652
_bci = kit->bci();
653
Parse* parser = kit->is_Parse();
654
int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
655
_block = block;
656
#endif
657
}
658
PreserveJVMState::~PreserveJVMState() {
659
GraphKit* kit = _kit;
660
#ifdef ASSERT
661
assert(kit->bci() == _bci, "bci must not shift");
662
Parse* parser = kit->is_Parse();
663
int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
664
assert(block == _block, "block must not shift");
665
#endif
666
kit->set_map(_map);
667
kit->set_sp(_sp);
668
}
669
670
671
//-----------------------------BuildCutout-------------------------------------
672
BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
673
: PreserveJVMState(kit)
674
{
675
assert(p->is_Con() || p->is_Bool(), "test must be a bool");
676
SafePointNode* outer_map = _map; // preserved map is caller's
677
SafePointNode* inner_map = kit->map();
678
IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
679
outer_map->set_control(kit->gvn().transform( new (kit->C) IfTrueNode(iff) ));
680
inner_map->set_control(kit->gvn().transform( new (kit->C) IfFalseNode(iff) ));
681
}
682
BuildCutout::~BuildCutout() {
683
GraphKit* kit = _kit;
684
assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
685
}
686
687
//---------------------------PreserveReexecuteState----------------------------
688
PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
689
assert(!kit->stopped(), "must call stopped() before");
690
_kit = kit;
691
_sp = kit->sp();
692
_reexecute = kit->jvms()->_reexecute;
693
}
694
PreserveReexecuteState::~PreserveReexecuteState() {
695
if (_kit->stopped()) return;
696
_kit->jvms()->_reexecute = _reexecute;
697
_kit->set_sp(_sp);
698
}
699
700
//------------------------------clone_map--------------------------------------
701
// Implementation of PreserveJVMState
702
//
703
// Only clone_map(...) here. If this function is only used in the
704
// PreserveJVMState class we may want to get rid of this extra
705
// function eventually and do it all there.
706
707
SafePointNode* GraphKit::clone_map() {
708
if (map() == NULL) return NULL;
709
710
// Clone the memory edge first
711
Node* mem = MergeMemNode::make(C, map()->memory());
712
gvn().set_type_bottom(mem);
713
714
SafePointNode *clonemap = (SafePointNode*)map()->clone();
715
JVMState* jvms = this->jvms();
716
JVMState* clonejvms = jvms->clone_shallow(C);
717
clonemap->set_memory(mem);
718
clonemap->set_jvms(clonejvms);
719
clonejvms->set_map(clonemap);
720
record_for_igvn(clonemap);
721
gvn().set_type_bottom(clonemap);
722
return clonemap;
723
}
724
725
726
//-----------------------------set_map_clone-----------------------------------
727
void GraphKit::set_map_clone(SafePointNode* m) {
728
_map = m;
729
_map = clone_map();
730
_map->set_next_exception(NULL);
731
debug_only(verify_map());
732
}
733
734
735
//----------------------------kill_dead_locals---------------------------------
736
// Detect any locals which are known to be dead, and force them to top.
737
void GraphKit::kill_dead_locals() {
738
// Consult the liveness information for the locals. If any
739
// of them are unused, then they can be replaced by top(). This
740
// should help register allocation time and cut down on the size
741
// of the deoptimization information.
742
743
// This call is made from many of the bytecode handling
744
// subroutines called from the Big Switch in do_one_bytecode.
745
// Every bytecode which might include a slow path is responsible
746
// for killing its dead locals. The more consistent we
747
// are about killing deads, the fewer useless phis will be
748
// constructed for them at various merge points.
749
750
// bci can be -1 (InvocationEntryBci). We return the entry
751
// liveness for the method.
752
753
if (method() == NULL || method()->code_size() == 0) {
754
// We are building a graph for a call to a native method.
755
// All locals are live.
756
return;
757
}
758
759
ResourceMark rm;
760
761
// Consult the liveness information for the locals. If any
762
// of them are unused, then they can be replaced by top(). This
763
// should help register allocation time and cut down on the size
764
// of the deoptimization information.
765
MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
766
767
int len = (int)live_locals.size();
768
assert(len <= jvms()->loc_size(), "too many live locals");
769
for (int local = 0; local < len; local++) {
770
if (!live_locals.at(local)) {
771
set_local(local, top());
772
}
773
}
774
}
775
776
#ifdef ASSERT
777
//-------------------------dead_locals_are_killed------------------------------
778
// Return true if all dead locals are set to top in the map.
779
// Used to assert "clean" debug info at various points.
780
bool GraphKit::dead_locals_are_killed() {
781
if (method() == NULL || method()->code_size() == 0) {
782
// No locals need to be dead, so all is as it should be.
783
return true;
784
}
785
786
// Make sure somebody called kill_dead_locals upstream.
787
ResourceMark rm;
788
for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
789
if (jvms->loc_size() == 0) continue; // no locals to consult
790
SafePointNode* map = jvms->map();
791
ciMethod* method = jvms->method();
792
int bci = jvms->bci();
793
if (jvms == this->jvms()) {
794
bci = this->bci(); // it might not yet be synched
795
}
796
MethodLivenessResult live_locals = method->liveness_at_bci(bci);
797
int len = (int)live_locals.size();
798
if (!live_locals.is_valid() || len == 0)
799
// This method is trivial, or is poisoned by a breakpoint.
800
return true;
801
assert(len == jvms->loc_size(), "live map consistent with locals map");
802
for (int local = 0; local < len; local++) {
803
if (!live_locals.at(local) && map->local(jvms, local) != top()) {
804
if (PrintMiscellaneous && (Verbose || WizardMode)) {
805
tty->print_cr("Zombie local %d: ", local);
806
jvms->dump();
807
}
808
return false;
809
}
810
}
811
}
812
return true;
813
}
814
815
#endif //ASSERT
816
817
// Helper function for enforcing certain bytecodes to reexecute if
818
// deoptimization happens
819
static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
820
ciMethod* cur_method = jvms->method();
821
int cur_bci = jvms->bci();
822
if (cur_method != NULL && cur_bci != InvocationEntryBci) {
823
Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
824
return Interpreter::bytecode_should_reexecute(code) ||
825
is_anewarray && code == Bytecodes::_multianewarray;
826
// Reexecute _multianewarray bytecode which was replaced with
827
// sequence of [a]newarray. See Parse::do_multianewarray().
828
//
829
// Note: interpreter should not have it set since this optimization
830
// is limited by dimensions and guarded by flag so in some cases
831
// multianewarray() runtime calls will be generated and
832
// the bytecode should not be reexecutes (stack will not be reset).
833
} else
834
return false;
835
}
836
837
// Helper function for adding JVMState and debug information to node
838
void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
839
// Add the safepoint edges to the call (or other safepoint).
840
841
// Make sure dead locals are set to top. This
842
// should help register allocation time and cut down on the size
843
// of the deoptimization information.
844
assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
845
846
// Walk the inline list to fill in the correct set of JVMState's
847
// Also fill in the associated edges for each JVMState.
848
849
// If the bytecode needs to be reexecuted we need to put
850
// the arguments back on the stack.
851
const bool should_reexecute = jvms()->should_reexecute();
852
JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
853
854
// NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
855
// undefined if the bci is different. This is normal for Parse but it
856
// should not happen for LibraryCallKit because only one bci is processed.
857
assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
858
"in LibraryCallKit the reexecute bit should not change");
859
860
// If we are guaranteed to throw, we can prune everything but the
861
// input to the current bytecode.
862
bool can_prune_locals = false;
863
uint stack_slots_not_pruned = 0;
864
int inputs = 0, depth = 0;
865
if (must_throw) {
866
assert(method() == youngest_jvms->method(), "sanity");
867
if (compute_stack_effects(inputs, depth)) {
868
can_prune_locals = true;
869
stack_slots_not_pruned = inputs;
870
}
871
}
872
873
if (env()->should_retain_local_variables()) {
874
// At any safepoint, this method can get breakpointed, which would
875
// then require an immediate deoptimization.
876
can_prune_locals = false; // do not prune locals
877
stack_slots_not_pruned = 0;
878
}
879
880
// do not scribble on the input jvms
881
JVMState* out_jvms = youngest_jvms->clone_deep(C);
882
call->set_jvms(out_jvms); // Start jvms list for call node
883
884
// For a known set of bytecodes, the interpreter should reexecute them if
885
// deoptimization happens. We set the reexecute state for them here
886
if (out_jvms->is_reexecute_undefined() && //don't change if already specified
887
should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
888
out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
889
}
890
891
// Presize the call:
892
DEBUG_ONLY(uint non_debug_edges = call->req());
893
call->add_req_batch(top(), youngest_jvms->debug_depth());
894
assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
895
896
// Set up edges so that the call looks like this:
897
// Call [state:] ctl io mem fptr retadr
898
// [parms:] parm0 ... parmN
899
// [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
900
// [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
901
// [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
902
// Note that caller debug info precedes callee debug info.
903
904
// Fill pointer walks backwards from "young:" to "root:" in the diagram above:
905
uint debug_ptr = call->req();
906
907
// Loop over the map input edges associated with jvms, add them
908
// to the call node, & reset all offsets to match call node array.
909
for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
910
uint debug_end = debug_ptr;
911
uint debug_start = debug_ptr - in_jvms->debug_size();
912
debug_ptr = debug_start; // back up the ptr
913
914
uint p = debug_start; // walks forward in [debug_start, debug_end)
915
uint j, k, l;
916
SafePointNode* in_map = in_jvms->map();
917
out_jvms->set_map(call);
918
919
if (can_prune_locals) {
920
assert(in_jvms->method() == out_jvms->method(), "sanity");
921
// If the current throw can reach an exception handler in this JVMS,
922
// then we must keep everything live that can reach that handler.
923
// As a quick and dirty approximation, we look for any handlers at all.
924
if (in_jvms->method()->has_exception_handlers()) {
925
can_prune_locals = false;
926
}
927
}
928
929
// Add the Locals
930
k = in_jvms->locoff();
931
l = in_jvms->loc_size();
932
out_jvms->set_locoff(p);
933
if (!can_prune_locals) {
934
for (j = 0; j < l; j++)
935
call->set_req(p++, in_map->in(k+j));
936
} else {
937
p += l; // already set to top above by add_req_batch
938
}
939
940
// Add the Expression Stack
941
k = in_jvms->stkoff();
942
l = in_jvms->sp();
943
out_jvms->set_stkoff(p);
944
if (!can_prune_locals) {
945
for (j = 0; j < l; j++)
946
call->set_req(p++, in_map->in(k+j));
947
} else if (can_prune_locals && stack_slots_not_pruned != 0) {
948
// Divide stack into {S0,...,S1}, where S0 is set to top.
949
uint s1 = stack_slots_not_pruned;
950
stack_slots_not_pruned = 0; // for next iteration
951
if (s1 > l) s1 = l;
952
uint s0 = l - s1;
953
p += s0; // skip the tops preinstalled by add_req_batch
954
for (j = s0; j < l; j++)
955
call->set_req(p++, in_map->in(k+j));
956
} else {
957
p += l; // already set to top above by add_req_batch
958
}
959
960
// Add the Monitors
961
k = in_jvms->monoff();
962
l = in_jvms->mon_size();
963
out_jvms->set_monoff(p);
964
for (j = 0; j < l; j++)
965
call->set_req(p++, in_map->in(k+j));
966
967
// Copy any scalar object fields.
968
k = in_jvms->scloff();
969
l = in_jvms->scl_size();
970
out_jvms->set_scloff(p);
971
for (j = 0; j < l; j++)
972
call->set_req(p++, in_map->in(k+j));
973
974
// Finish the new jvms.
975
out_jvms->set_endoff(p);
976
977
assert(out_jvms->endoff() == debug_end, "fill ptr must match");
978
assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
979
assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
980
assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
981
assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
982
assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
983
984
// Update the two tail pointers in parallel.
985
out_jvms = out_jvms->caller();
986
in_jvms = in_jvms->caller();
987
}
988
989
assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
990
991
// Test the correctness of JVMState::debug_xxx accessors:
992
assert(call->jvms()->debug_start() == non_debug_edges, "");
993
assert(call->jvms()->debug_end() == call->req(), "");
994
assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
995
}
996
997
bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
998
Bytecodes::Code code = java_bc();
999
if (code == Bytecodes::_wide) {
1000
code = method()->java_code_at_bci(bci() + 1);
1001
}
1002
1003
BasicType rtype = T_ILLEGAL;
1004
int rsize = 0;
1005
1006
if (code != Bytecodes::_illegal) {
1007
depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1008
rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1009
if (rtype < T_CONFLICT)
1010
rsize = type2size[rtype];
1011
}
1012
1013
switch (code) {
1014
case Bytecodes::_illegal:
1015
return false;
1016
1017
case Bytecodes::_ldc:
1018
case Bytecodes::_ldc_w:
1019
case Bytecodes::_ldc2_w:
1020
inputs = 0;
1021
break;
1022
1023
case Bytecodes::_dup: inputs = 1; break;
1024
case Bytecodes::_dup_x1: inputs = 2; break;
1025
case Bytecodes::_dup_x2: inputs = 3; break;
1026
case Bytecodes::_dup2: inputs = 2; break;
1027
case Bytecodes::_dup2_x1: inputs = 3; break;
1028
case Bytecodes::_dup2_x2: inputs = 4; break;
1029
case Bytecodes::_swap: inputs = 2; break;
1030
case Bytecodes::_arraylength: inputs = 1; break;
1031
1032
case Bytecodes::_getstatic:
1033
case Bytecodes::_putstatic:
1034
case Bytecodes::_getfield:
1035
case Bytecodes::_putfield:
1036
{
1037
bool ignored_will_link;
1038
ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1039
int size = field->type()->size();
1040
bool is_get = (depth >= 0), is_static = (depth & 1);
1041
inputs = (is_static ? 0 : 1);
1042
if (is_get) {
1043
depth = size - inputs;
1044
} else {
1045
inputs += size; // putxxx pops the value from the stack
1046
depth = - inputs;
1047
}
1048
}
1049
break;
1050
1051
case Bytecodes::_invokevirtual:
1052
case Bytecodes::_invokespecial:
1053
case Bytecodes::_invokestatic:
1054
case Bytecodes::_invokedynamic:
1055
case Bytecodes::_invokeinterface:
1056
{
1057
bool ignored_will_link;
1058
ciSignature* declared_signature = NULL;
1059
ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1060
assert(declared_signature != NULL, "cannot be null");
1061
inputs = declared_signature->arg_size_for_bc(code);
1062
int size = declared_signature->return_type()->size();
1063
depth = size - inputs;
1064
}
1065
break;
1066
1067
case Bytecodes::_multianewarray:
1068
{
1069
ciBytecodeStream iter(method());
1070
iter.reset_to_bci(bci());
1071
iter.next();
1072
inputs = iter.get_dimensions();
1073
assert(rsize == 1, "");
1074
depth = rsize - inputs;
1075
}
1076
break;
1077
1078
case Bytecodes::_ireturn:
1079
case Bytecodes::_lreturn:
1080
case Bytecodes::_freturn:
1081
case Bytecodes::_dreturn:
1082
case Bytecodes::_areturn:
1083
assert(rsize = -depth, "");
1084
inputs = rsize;
1085
break;
1086
1087
case Bytecodes::_jsr:
1088
case Bytecodes::_jsr_w:
1089
inputs = 0;
1090
depth = 1; // S.B. depth=1, not zero
1091
break;
1092
1093
default:
1094
// bytecode produces a typed result
1095
inputs = rsize - depth;
1096
assert(inputs >= 0, "");
1097
break;
1098
}
1099
1100
#ifdef ASSERT
1101
// spot check
1102
int outputs = depth + inputs;
1103
assert(outputs >= 0, "sanity");
1104
switch (code) {
1105
case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1106
case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break;
1107
case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break;
1108
case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break;
1109
case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break;
1110
}
1111
#endif //ASSERT
1112
1113
return true;
1114
}
1115
1116
1117
1118
//------------------------------basic_plus_adr---------------------------------
1119
Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1120
// short-circuit a common case
1121
if (offset == intcon(0)) return ptr;
1122
return _gvn.transform( new (C) AddPNode(base, ptr, offset) );
1123
}
1124
1125
Node* GraphKit::ConvI2L(Node* offset) {
1126
// short-circuit a common case
1127
jint offset_con = find_int_con(offset, Type::OffsetBot);
1128
if (offset_con != Type::OffsetBot) {
1129
return longcon((jlong) offset_con);
1130
}
1131
return _gvn.transform( new (C) ConvI2LNode(offset));
1132
}
1133
1134
Node* GraphKit::ConvI2UL(Node* offset) {
1135
juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1136
if (offset_con != (juint) Type::OffsetBot) {
1137
return longcon((julong) offset_con);
1138
}
1139
Node* conv = _gvn.transform( new (C) ConvI2LNode(offset));
1140
Node* mask = _gvn.transform( ConLNode::make(C, (julong) max_juint) );
1141
return _gvn.transform( new (C) AndLNode(conv, mask) );
1142
}
1143
1144
Node* GraphKit::ConvL2I(Node* offset) {
1145
// short-circuit a common case
1146
jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1147
if (offset_con != (jlong)Type::OffsetBot) {
1148
return intcon((int) offset_con);
1149
}
1150
return _gvn.transform( new (C) ConvL2INode(offset));
1151
}
1152
1153
//-------------------------load_object_klass-----------------------------------
1154
Node* GraphKit::load_object_klass(Node* obj) {
1155
// Special-case a fresh allocation to avoid building nodes:
1156
Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1157
if (akls != NULL) return akls;
1158
Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1159
return _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1160
}
1161
1162
//-------------------------load_array_length-----------------------------------
1163
Node* GraphKit::load_array_length(Node* array) {
1164
// Special-case a fresh allocation to avoid building nodes:
1165
AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1166
Node *alen;
1167
if (alloc == NULL) {
1168
Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1169
alen = _gvn.transform( new (C) LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1170
} else {
1171
alen = alloc->Ideal_length();
1172
Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1173
if (ccast != alen) {
1174
alen = _gvn.transform(ccast);
1175
}
1176
}
1177
return alen;
1178
}
1179
1180
//------------------------------do_null_check----------------------------------
1181
// Helper function to do a NULL pointer check. Returned value is
1182
// the incoming address with NULL casted away. You are allowed to use the
1183
// not-null value only if you are control dependent on the test.
1184
extern int explicit_null_checks_inserted,
1185
explicit_null_checks_elided;
1186
Node* GraphKit::null_check_common(Node* value, BasicType type,
1187
// optional arguments for variations:
1188
bool assert_null,
1189
Node* *null_control) {
1190
assert(!assert_null || null_control == NULL, "not both at once");
1191
if (stopped()) return top();
1192
if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) {
1193
// For some performance testing, we may wish to suppress null checking.
1194
value = cast_not_null(value); // Make it appear to be non-null (4962416).
1195
return value;
1196
}
1197
explicit_null_checks_inserted++;
1198
1199
// Construct NULL check
1200
Node *chk = NULL;
1201
switch(type) {
1202
case T_LONG : chk = new (C) CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1203
case T_INT : chk = new (C) CmpINode(value, _gvn.intcon(0)); break;
1204
case T_ARRAY : // fall through
1205
type = T_OBJECT; // simplify further tests
1206
case T_OBJECT : {
1207
const Type *t = _gvn.type( value );
1208
1209
const TypeOopPtr* tp = t->isa_oopptr();
1210
if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1211
// Only for do_null_check, not any of its siblings:
1212
&& !assert_null && null_control == NULL) {
1213
// Usually, any field access or invocation on an unloaded oop type
1214
// will simply fail to link, since the statically linked class is
1215
// likely also to be unloaded. However, in -Xcomp mode, sometimes
1216
// the static class is loaded but the sharper oop type is not.
1217
// Rather than checking for this obscure case in lots of places,
1218
// we simply observe that a null check on an unloaded class
1219
// will always be followed by a nonsense operation, so we
1220
// can just issue the uncommon trap here.
1221
// Our access to the unloaded class will only be correct
1222
// after it has been loaded and initialized, which requires
1223
// a trip through the interpreter.
1224
#ifndef PRODUCT
1225
if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1226
#endif
1227
uncommon_trap(Deoptimization::Reason_unloaded,
1228
Deoptimization::Action_reinterpret,
1229
tp->klass(), "!loaded");
1230
return top();
1231
}
1232
1233
if (assert_null) {
1234
// See if the type is contained in NULL_PTR.
1235
// If so, then the value is already null.
1236
if (t->higher_equal(TypePtr::NULL_PTR)) {
1237
explicit_null_checks_elided++;
1238
return value; // Elided null assert quickly!
1239
}
1240
} else {
1241
// See if mixing in the NULL pointer changes type.
1242
// If so, then the NULL pointer was not allowed in the original
1243
// type. In other words, "value" was not-null.
1244
if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1245
// same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1246
explicit_null_checks_elided++;
1247
return value; // Elided null check quickly!
1248
}
1249
}
1250
chk = new (C) CmpPNode( value, null() );
1251
break;
1252
}
1253
1254
default:
1255
fatal(err_msg_res("unexpected type: %s", type2name(type)));
1256
}
1257
assert(chk != NULL, "sanity check");
1258
chk = _gvn.transform(chk);
1259
1260
BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1261
BoolNode *btst = new (C) BoolNode( chk, btest);
1262
Node *tst = _gvn.transform( btst );
1263
1264
//-----------
1265
// if peephole optimizations occurred, a prior test existed.
1266
// If a prior test existed, maybe it dominates as we can avoid this test.
1267
if (tst != btst && type == T_OBJECT) {
1268
// At this point we want to scan up the CFG to see if we can
1269
// find an identical test (and so avoid this test altogether).
1270
Node *cfg = control();
1271
int depth = 0;
1272
while( depth < 16 ) { // Limit search depth for speed
1273
if( cfg->Opcode() == Op_IfTrue &&
1274
cfg->in(0)->in(1) == tst ) {
1275
// Found prior test. Use "cast_not_null" to construct an identical
1276
// CastPP (and hence hash to) as already exists for the prior test.
1277
// Return that casted value.
1278
if (assert_null) {
1279
replace_in_map(value, null());
1280
return null(); // do not issue the redundant test
1281
}
1282
Node *oldcontrol = control();
1283
set_control(cfg);
1284
Node *res = cast_not_null(value);
1285
set_control(oldcontrol);
1286
explicit_null_checks_elided++;
1287
return res;
1288
}
1289
cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1290
if (cfg == NULL) break; // Quit at region nodes
1291
depth++;
1292
}
1293
}
1294
1295
//-----------
1296
// Branch to failure if null
1297
float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1298
Deoptimization::DeoptReason reason;
1299
if (assert_null)
1300
reason = Deoptimization::Reason_null_assert;
1301
else if (type == T_OBJECT)
1302
reason = Deoptimization::Reason_null_check;
1303
else
1304
reason = Deoptimization::Reason_div0_check;
1305
1306
// %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1307
// ciMethodData::has_trap_at will return a conservative -1 if any
1308
// must-be-null assertion has failed. This could cause performance
1309
// problems for a method after its first do_null_assert failure.
1310
// Consider using 'Reason_class_check' instead?
1311
1312
// To cause an implicit null check, we set the not-null probability
1313
// to the maximum (PROB_MAX). For an explicit check the probability
1314
// is set to a smaller value.
1315
if (null_control != NULL || too_many_traps(reason)) {
1316
// probability is less likely
1317
ok_prob = PROB_LIKELY_MAG(3);
1318
} else if (!assert_null &&
1319
(ImplicitNullCheckThreshold > 0) &&
1320
method() != NULL &&
1321
(method()->method_data()->trap_count(reason)
1322
>= (uint)ImplicitNullCheckThreshold)) {
1323
ok_prob = PROB_LIKELY_MAG(3);
1324
}
1325
1326
if (null_control != NULL) {
1327
IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1328
Node* null_true = _gvn.transform( new (C) IfFalseNode(iff));
1329
set_control( _gvn.transform( new (C) IfTrueNode(iff)));
1330
if (null_true == top())
1331
explicit_null_checks_elided++;
1332
(*null_control) = null_true;
1333
} else {
1334
BuildCutout unless(this, tst, ok_prob);
1335
// Check for optimizer eliding test at parse time
1336
if (stopped()) {
1337
// Failure not possible; do not bother making uncommon trap.
1338
explicit_null_checks_elided++;
1339
} else if (assert_null) {
1340
uncommon_trap(reason,
1341
Deoptimization::Action_make_not_entrant,
1342
NULL, "assert_null");
1343
} else {
1344
replace_in_map(value, zerocon(type));
1345
builtin_throw(reason);
1346
}
1347
}
1348
1349
// Must throw exception, fall-thru not possible?
1350
if (stopped()) {
1351
return top(); // No result
1352
}
1353
1354
if (assert_null) {
1355
// Cast obj to null on this path.
1356
replace_in_map(value, zerocon(type));
1357
return zerocon(type);
1358
}
1359
1360
// Cast obj to not-null on this path, if there is no null_control.
1361
// (If there is a null_control, a non-null value may come back to haunt us.)
1362
if (type == T_OBJECT) {
1363
Node* cast = cast_not_null(value, false);
1364
if (null_control == NULL || (*null_control) == top())
1365
replace_in_map(value, cast);
1366
value = cast;
1367
}
1368
1369
return value;
1370
}
1371
1372
1373
//------------------------------cast_not_null----------------------------------
1374
// Cast obj to not-null on this path
1375
Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1376
const Type *t = _gvn.type(obj);
1377
const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1378
// Object is already not-null?
1379
if( t == t_not_null ) return obj;
1380
1381
Node *cast = new (C) CastPPNode(obj,t_not_null);
1382
cast->init_req(0, control());
1383
cast = _gvn.transform( cast );
1384
1385
// Scan for instances of 'obj' in the current JVM mapping.
1386
// These instances are known to be not-null after the test.
1387
if (do_replace_in_map)
1388
replace_in_map(obj, cast);
1389
1390
return cast; // Return casted value
1391
}
1392
1393
1394
//--------------------------replace_in_map-------------------------------------
1395
void GraphKit::replace_in_map(Node* old, Node* neww) {
1396
if (old == neww) {
1397
return;
1398
}
1399
1400
map()->replace_edge(old, neww);
1401
1402
// Note: This operation potentially replaces any edge
1403
// on the map. This includes locals, stack, and monitors
1404
// of the current (innermost) JVM state.
1405
1406
// don't let inconsistent types from profiling escape this
1407
// method
1408
1409
const Type* told = _gvn.type(old);
1410
const Type* tnew = _gvn.type(neww);
1411
1412
if (!tnew->higher_equal(told)) {
1413
return;
1414
}
1415
1416
map()->record_replaced_node(old, neww);
1417
}
1418
1419
1420
//=============================================================================
1421
//--------------------------------memory---------------------------------------
1422
Node* GraphKit::memory(uint alias_idx) {
1423
MergeMemNode* mem = merged_memory();
1424
Node* p = mem->memory_at(alias_idx);
1425
_gvn.set_type(p, Type::MEMORY); // must be mapped
1426
return p;
1427
}
1428
1429
//-----------------------------reset_memory------------------------------------
1430
Node* GraphKit::reset_memory() {
1431
Node* mem = map()->memory();
1432
// do not use this node for any more parsing!
1433
debug_only( map()->set_memory((Node*)NULL) );
1434
return _gvn.transform( mem );
1435
}
1436
1437
//------------------------------set_all_memory---------------------------------
1438
void GraphKit::set_all_memory(Node* newmem) {
1439
Node* mergemem = MergeMemNode::make(C, newmem);
1440
gvn().set_type_bottom(mergemem);
1441
map()->set_memory(mergemem);
1442
}
1443
1444
//------------------------------set_all_memory_call----------------------------
1445
void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1446
Node* newmem = _gvn.transform( new (C) ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1447
set_all_memory(newmem);
1448
}
1449
1450
//=============================================================================
1451
//
1452
// parser factory methods for MemNodes
1453
//
1454
// These are layered on top of the factory methods in LoadNode and StoreNode,
1455
// and integrate with the parser's memory state and _gvn engine.
1456
//
1457
1458
// factory methods in "int adr_idx"
1459
Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1460
int adr_idx,
1461
MemNode::MemOrd mo,
1462
LoadNode::ControlDependency control_dependency,
1463
bool require_atomic_access,
1464
bool unaligned,
1465
bool mismatched) {
1466
assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1467
const TypePtr* adr_type = NULL; // debug-mode-only argument
1468
debug_only(adr_type = C->get_adr_type(adr_idx));
1469
Node* mem = memory(adr_idx);
1470
Node* ld;
1471
if (require_atomic_access && bt == T_LONG) {
1472
ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t, mo, control_dependency);
1473
} else if (require_atomic_access && bt == T_DOUBLE) {
1474
ld = LoadDNode::make_atomic(C, ctl, mem, adr, adr_type, t, mo, control_dependency);
1475
} else {
1476
ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency);
1477
}
1478
if (unaligned) {
1479
ld->as_Load()->set_unaligned_access();
1480
}
1481
if (mismatched) {
1482
ld->as_Load()->set_mismatched_access();
1483
}
1484
ld = _gvn.transform(ld);
1485
if ((bt == T_OBJECT) && C->do_escape_analysis() || C->eliminate_boxing()) {
1486
// Improve graph before escape analysis and boxing elimination.
1487
record_for_igvn(ld);
1488
}
1489
return ld;
1490
}
1491
1492
Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1493
int adr_idx,
1494
MemNode::MemOrd mo,
1495
bool require_atomic_access,
1496
bool unaligned,
1497
bool mismatched) {
1498
assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1499
const TypePtr* adr_type = NULL;
1500
debug_only(adr_type = C->get_adr_type(adr_idx));
1501
Node *mem = memory(adr_idx);
1502
Node* st;
1503
if (require_atomic_access && bt == T_LONG) {
1504
st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val, mo);
1505
} else if (require_atomic_access && bt == T_DOUBLE) {
1506
st = StoreDNode::make_atomic(C, ctl, mem, adr, adr_type, val, mo);
1507
} else {
1508
st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo);
1509
}
1510
if (unaligned) {
1511
st->as_Store()->set_unaligned_access();
1512
}
1513
if (mismatched) {
1514
st->as_Store()->set_mismatched_access();
1515
}
1516
st = _gvn.transform(st);
1517
set_memory(st, adr_idx);
1518
// Back-to-back stores can only remove intermediate store with DU info
1519
// so push on worklist for optimizer.
1520
if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1521
record_for_igvn(st);
1522
1523
return st;
1524
}
1525
1526
1527
void GraphKit::pre_barrier(bool do_load,
1528
Node* ctl,
1529
Node* obj,
1530
Node* adr,
1531
uint adr_idx,
1532
Node* val,
1533
const TypeOopPtr* val_type,
1534
Node* pre_val,
1535
BasicType bt) {
1536
1537
BarrierSet* bs = Universe::heap()->barrier_set();
1538
set_control(ctl);
1539
switch (bs->kind()) {
1540
case BarrierSet::G1SATBCT:
1541
case BarrierSet::G1SATBCTLogging:
1542
g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1543
break;
1544
case BarrierSet::ShenandoahBarrierSet:
1545
if (ShenandoahSATBBarrier) {
1546
g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1547
}
1548
break;
1549
case BarrierSet::CardTableModRef:
1550
case BarrierSet::CardTableExtension:
1551
case BarrierSet::ModRef:
1552
break;
1553
1554
case BarrierSet::Other:
1555
default :
1556
ShouldNotReachHere();
1557
1558
}
1559
}
1560
1561
bool GraphKit::can_move_pre_barrier() const {
1562
BarrierSet* bs = Universe::heap()->barrier_set();
1563
switch (bs->kind()) {
1564
case BarrierSet::G1SATBCT:
1565
case BarrierSet::G1SATBCTLogging:
1566
case BarrierSet::ShenandoahBarrierSet:
1567
return true; // Can move it if no safepoint
1568
1569
case BarrierSet::CardTableModRef:
1570
case BarrierSet::CardTableExtension:
1571
case BarrierSet::ModRef:
1572
return true; // There is no pre-barrier
1573
1574
case BarrierSet::Other:
1575
default :
1576
ShouldNotReachHere();
1577
}
1578
return false;
1579
}
1580
1581
void GraphKit::post_barrier(Node* ctl,
1582
Node* store,
1583
Node* obj,
1584
Node* adr,
1585
uint adr_idx,
1586
Node* val,
1587
BasicType bt,
1588
bool use_precise) {
1589
BarrierSet* bs = Universe::heap()->barrier_set();
1590
set_control(ctl);
1591
switch (bs->kind()) {
1592
case BarrierSet::G1SATBCT:
1593
case BarrierSet::G1SATBCTLogging:
1594
g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1595
break;
1596
case BarrierSet::ShenandoahBarrierSet:
1597
if (ShenandoahStoreValEnqueueBarrier) {
1598
g1_write_barrier_pre(false, NULL, NULL, max_juint, NULL, NULL, val, bt);
1599
}
1600
break;
1601
case BarrierSet::CardTableModRef:
1602
case BarrierSet::CardTableExtension:
1603
write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1604
break;
1605
1606
case BarrierSet::ModRef:
1607
break;
1608
1609
case BarrierSet::Other:
1610
default :
1611
ShouldNotReachHere();
1612
1613
}
1614
}
1615
1616
Node* GraphKit::store_oop(Node* ctl,
1617
Node* obj,
1618
Node* adr,
1619
const TypePtr* adr_type,
1620
Node* val,
1621
const TypeOopPtr* val_type,
1622
BasicType bt,
1623
bool use_precise,
1624
MemNode::MemOrd mo,
1625
bool mismatched) {
1626
// Transformation of a value which could be NULL pointer (CastPP #NULL)
1627
// could be delayed during Parse (for example, in adjust_map_after_if()).
1628
// Execute transformation here to avoid barrier generation in such case.
1629
if (_gvn.type(val) == TypePtr::NULL_PTR)
1630
val = _gvn.makecon(TypePtr::NULL_PTR);
1631
1632
set_control(ctl);
1633
if (stopped()) return top(); // Dead path ?
1634
1635
assert(bt == T_OBJECT, "sanity");
1636
assert(val != NULL, "not dead path");
1637
uint adr_idx = C->get_alias_index(adr_type);
1638
assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1639
1640
pre_barrier(true /* do_load */,
1641
control(), obj, adr, adr_idx, val, val_type,
1642
NULL /* pre_val */,
1643
bt);
1644
1645
Node* store = store_to_memory(control(), adr, val, bt, adr_idx, mo, mismatched);
1646
post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1647
return store;
1648
}
1649
1650
// Could be an array or object we don't know at compile time (unsafe ref.)
1651
Node* GraphKit::store_oop_to_unknown(Node* ctl,
1652
Node* obj, // containing obj
1653
Node* adr, // actual adress to store val at
1654
const TypePtr* adr_type,
1655
Node* val,
1656
BasicType bt,
1657
MemNode::MemOrd mo,
1658
bool mismatched) {
1659
Compile::AliasType* at = C->alias_type(adr_type);
1660
const TypeOopPtr* val_type = NULL;
1661
if (adr_type->isa_instptr()) {
1662
if (at->field() != NULL) {
1663
// known field. This code is a copy of the do_put_xxx logic.
1664
ciField* field = at->field();
1665
if (!field->type()->is_loaded()) {
1666
val_type = TypeInstPtr::BOTTOM;
1667
} else {
1668
val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1669
}
1670
}
1671
} else if (adr_type->isa_aryptr()) {
1672
val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1673
}
1674
if (val_type == NULL) {
1675
val_type = TypeInstPtr::BOTTOM;
1676
}
1677
return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, mo, mismatched);
1678
}
1679
1680
1681
//-------------------------array_element_address-------------------------
1682
Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1683
const TypeInt* sizetype, Node* ctrl) {
1684
uint shift = exact_log2(type2aelembytes(elembt));
1685
uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1686
1687
// short-circuit a common case (saves lots of confusing waste motion)
1688
jint idx_con = find_int_con(idx, -1);
1689
if (idx_con >= 0) {
1690
intptr_t offset = header + ((intptr_t)idx_con << shift);
1691
return basic_plus_adr(ary, offset);
1692
}
1693
1694
// must be correct type for alignment purposes
1695
Node* base = basic_plus_adr(ary, header);
1696
#ifdef _LP64
1697
// The scaled index operand to AddP must be a clean 64-bit value.
1698
// Java allows a 32-bit int to be incremented to a negative
1699
// value, which appears in a 64-bit register as a large
1700
// positive number. Using that large positive number as an
1701
// operand in pointer arithmetic has bad consequences.
1702
// On the other hand, 32-bit overflow is rare, and the possibility
1703
// can often be excluded, if we annotate the ConvI2L node with
1704
// a type assertion that its value is known to be a small positive
1705
// number. (The prior range check has ensured this.)
1706
// This assertion is used by ConvI2LNode::Ideal.
1707
int index_max = max_jint - 1; // array size is max_jint, index is one less
1708
if (sizetype != NULL) index_max = sizetype->_hi - 1;
1709
const TypeInt* iidxtype = TypeInt::make(0, index_max, Type::WidenMax);
1710
idx = C->constrained_convI2L(&_gvn, idx, iidxtype, ctrl);
1711
#endif
1712
Node* scale = _gvn.transform( new (C) LShiftXNode(idx, intcon(shift)) );
1713
return basic_plus_adr(ary, base, scale);
1714
}
1715
1716
//-------------------------load_array_element-------------------------
1717
Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1718
const Type* elemtype = arytype->elem();
1719
BasicType elembt = elemtype->array_element_basic_type();
1720
Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1721
if (elembt == T_NARROWOOP) {
1722
elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1723
}
1724
Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered);
1725
#if INCLUDE_ALL_GCS
1726
if (UseShenandoahGC && (elembt == T_OBJECT || elembt == T_ARRAY)) {
1727
ld = ShenandoahBarrierSetC2::bsc2()->load_reference_barrier(this, ld);
1728
}
1729
#endif
1730
return ld;
1731
}
1732
1733
//-------------------------set_arguments_for_java_call-------------------------
1734
// Arguments (pre-popped from the stack) are taken from the JVMS.
1735
void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1736
// Add the call arguments:
1737
uint nargs = call->method()->arg_size();
1738
for (uint i = 0; i < nargs; i++) {
1739
Node* arg = argument(i);
1740
call->init_req(i + TypeFunc::Parms, arg);
1741
}
1742
}
1743
1744
//---------------------------set_edges_for_java_call---------------------------
1745
// Connect a newly created call into the current JVMS.
1746
// A return value node (if any) is returned from set_edges_for_java_call.
1747
void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1748
1749
// Add the predefined inputs:
1750
call->init_req( TypeFunc::Control, control() );
1751
call->init_req( TypeFunc::I_O , i_o() );
1752
call->init_req( TypeFunc::Memory , reset_memory() );
1753
call->init_req( TypeFunc::FramePtr, frameptr() );
1754
call->init_req( TypeFunc::ReturnAdr, top() );
1755
1756
add_safepoint_edges(call, must_throw);
1757
1758
Node* xcall = _gvn.transform(call);
1759
1760
if (xcall == top()) {
1761
set_control(top());
1762
return;
1763
}
1764
assert(xcall == call, "call identity is stable");
1765
1766
// Re-use the current map to produce the result.
1767
1768
set_control(_gvn.transform(new (C) ProjNode(call, TypeFunc::Control)));
1769
set_i_o( _gvn.transform(new (C) ProjNode(call, TypeFunc::I_O , separate_io_proj)));
1770
set_all_memory_call(xcall, separate_io_proj);
1771
1772
//return xcall; // no need, caller already has it
1773
}
1774
1775
Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1776
if (stopped()) return top(); // maybe the call folded up?
1777
1778
// Capture the return value, if any.
1779
Node* ret;
1780
if (call->method() == NULL ||
1781
call->method()->return_type()->basic_type() == T_VOID)
1782
ret = top();
1783
else ret = _gvn.transform(new (C) ProjNode(call, TypeFunc::Parms));
1784
1785
// Note: Since any out-of-line call can produce an exception,
1786
// we always insert an I_O projection from the call into the result.
1787
1788
make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1789
1790
if (separate_io_proj) {
1791
// The caller requested separate projections be used by the fall
1792
// through and exceptional paths, so replace the projections for
1793
// the fall through path.
1794
set_i_o(_gvn.transform( new (C) ProjNode(call, TypeFunc::I_O) ));
1795
set_all_memory(_gvn.transform( new (C) ProjNode(call, TypeFunc::Memory) ));
1796
}
1797
return ret;
1798
}
1799
1800
//--------------------set_predefined_input_for_runtime_call--------------------
1801
// Reading and setting the memory state is way conservative here.
1802
// The real problem is that I am not doing real Type analysis on memory,
1803
// so I cannot distinguish card mark stores from other stores. Across a GC
1804
// point the Store Barrier and the card mark memory has to agree. I cannot
1805
// have a card mark store and its barrier split across the GC point from
1806
// either above or below. Here I get that to happen by reading ALL of memory.
1807
// A better answer would be to separate out card marks from other memory.
1808
// For now, return the input memory state, so that it can be reused
1809
// after the call, if this call has restricted memory effects.
1810
Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem) {
1811
// Set fixed predefined input arguments
1812
Node* memory = reset_memory();
1813
Node* m = narrow_mem == NULL ? memory : narrow_mem;
1814
call->init_req( TypeFunc::Control, control() );
1815
call->init_req( TypeFunc::I_O, top() ); // does no i/o
1816
call->init_req( TypeFunc::Memory, m ); // may gc ptrs
1817
call->init_req( TypeFunc::FramePtr, frameptr() );
1818
call->init_req( TypeFunc::ReturnAdr, top() );
1819
return memory;
1820
}
1821
1822
//-------------------set_predefined_output_for_runtime_call--------------------
1823
// Set control and memory (not i_o) from the call.
1824
// If keep_mem is not NULL, use it for the output state,
1825
// except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1826
// If hook_mem is NULL, this call produces no memory effects at all.
1827
// If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1828
// then only that memory slice is taken from the call.
1829
// In the last case, we must put an appropriate memory barrier before
1830
// the call, so as to create the correct anti-dependencies on loads
1831
// preceding the call.
1832
void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1833
Node* keep_mem,
1834
const TypePtr* hook_mem) {
1835
// no i/o
1836
set_control(_gvn.transform( new (C) ProjNode(call,TypeFunc::Control) ));
1837
if (keep_mem) {
1838
// First clone the existing memory state
1839
set_all_memory(keep_mem);
1840
if (hook_mem != NULL) {
1841
// Make memory for the call
1842
Node* mem = _gvn.transform( new (C) ProjNode(call, TypeFunc::Memory) );
1843
// Set the RawPtr memory state only. This covers all the heap top/GC stuff
1844
// We also use hook_mem to extract specific effects from arraycopy stubs.
1845
set_memory(mem, hook_mem);
1846
}
1847
// ...else the call has NO memory effects.
1848
1849
// Make sure the call advertises its memory effects precisely.
1850
// This lets us build accurate anti-dependences in gcm.cpp.
1851
assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1852
"call node must be constructed correctly");
1853
} else {
1854
assert(hook_mem == NULL, "");
1855
// This is not a "slow path" call; all memory comes from the call.
1856
set_all_memory_call(call);
1857
}
1858
}
1859
1860
1861
// Replace the call with the current state of the kit.
1862
void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) {
1863
JVMState* ejvms = NULL;
1864
if (has_exceptions()) {
1865
ejvms = transfer_exceptions_into_jvms();
1866
}
1867
1868
ReplacedNodes replaced_nodes = map()->replaced_nodes();
1869
ReplacedNodes replaced_nodes_exception;
1870
Node* ex_ctl = top();
1871
1872
SafePointNode* final_state = stop();
1873
1874
// Find all the needed outputs of this call
1875
CallProjections callprojs;
1876
call->extract_projections(&callprojs, true);
1877
1878
Node* init_mem = call->in(TypeFunc::Memory);
1879
Node* final_mem = final_state->in(TypeFunc::Memory);
1880
Node* final_ctl = final_state->in(TypeFunc::Control);
1881
Node* final_io = final_state->in(TypeFunc::I_O);
1882
1883
// Replace all the old call edges with the edges from the inlining result
1884
if (callprojs.fallthrough_catchproj != NULL) {
1885
C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1886
}
1887
if (callprojs.fallthrough_memproj != NULL) {
1888
if (final_mem->is_MergeMem()) {
1889
// Parser's exits MergeMem was not transformed but may be optimized
1890
final_mem = _gvn.transform(final_mem);
1891
}
1892
C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem);
1893
}
1894
if (callprojs.fallthrough_ioproj != NULL) {
1895
C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io);
1896
}
1897
1898
// Replace the result with the new result if it exists and is used
1899
if (callprojs.resproj != NULL && result != NULL) {
1900
C->gvn_replace_by(callprojs.resproj, result);
1901
}
1902
1903
if (ejvms == NULL) {
1904
// No exception edges to simply kill off those paths
1905
if (callprojs.catchall_catchproj != NULL) {
1906
C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1907
}
1908
if (callprojs.catchall_memproj != NULL) {
1909
C->gvn_replace_by(callprojs.catchall_memproj, C->top());
1910
}
1911
if (callprojs.catchall_ioproj != NULL) {
1912
C->gvn_replace_by(callprojs.catchall_ioproj, C->top());
1913
}
1914
// Replace the old exception object with top
1915
if (callprojs.exobj != NULL) {
1916
C->gvn_replace_by(callprojs.exobj, C->top());
1917
}
1918
} else {
1919
GraphKit ekit(ejvms);
1920
1921
// Load my combined exception state into the kit, with all phis transformed:
1922
SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1923
replaced_nodes_exception = ex_map->replaced_nodes();
1924
1925
Node* ex_oop = ekit.use_exception_state(ex_map);
1926
1927
if (callprojs.catchall_catchproj != NULL) {
1928
C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1929
ex_ctl = ekit.control();
1930
}
1931
if (callprojs.catchall_memproj != NULL) {
1932
C->gvn_replace_by(callprojs.catchall_memproj, ekit.reset_memory());
1933
}
1934
if (callprojs.catchall_ioproj != NULL) {
1935
C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o());
1936
}
1937
1938
// Replace the old exception object with the newly created one
1939
if (callprojs.exobj != NULL) {
1940
C->gvn_replace_by(callprojs.exobj, ex_oop);
1941
}
1942
}
1943
1944
// Disconnect the call from the graph
1945
call->disconnect_inputs(NULL, C);
1946
C->gvn_replace_by(call, C->top());
1947
1948
// Clean up any MergeMems that feed other MergeMems since the
1949
// optimizer doesn't like that.
1950
if (final_mem->is_MergeMem()) {
1951
Node_List wl;
1952
for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1953
Node* m = i.get();
1954
if (m->is_MergeMem() && !wl.contains(m)) {
1955
wl.push(m);
1956
}
1957
}
1958
while (wl.size() > 0) {
1959
_gvn.transform(wl.pop());
1960
}
1961
}
1962
1963
if (callprojs.fallthrough_catchproj != NULL && !final_ctl->is_top() && do_replaced_nodes) {
1964
replaced_nodes.apply(C, final_ctl);
1965
}
1966
if (!ex_ctl->is_top() && do_replaced_nodes) {
1967
replaced_nodes_exception.apply(C, ex_ctl);
1968
}
1969
}
1970
1971
1972
//------------------------------increment_counter------------------------------
1973
// for statistics: increment a VM counter by 1
1974
1975
void GraphKit::increment_counter(address counter_addr) {
1976
Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1977
increment_counter(adr1);
1978
}
1979
1980
void GraphKit::increment_counter(Node* counter_addr) {
1981
int adr_type = Compile::AliasIdxRaw;
1982
Node* ctrl = control();
1983
Node* cnt = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
1984
Node* incr = _gvn.transform(new (C) AddINode(cnt, _gvn.intcon(1)));
1985
store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered);
1986
}
1987
1988
1989
//------------------------------uncommon_trap----------------------------------
1990
// Bail out to the interpreter in mid-method. Implemented by calling the
1991
// uncommon_trap blob. This helper function inserts a runtime call with the
1992
// right debug info.
1993
void GraphKit::uncommon_trap(int trap_request,
1994
ciKlass* klass, const char* comment,
1995
bool must_throw,
1996
bool keep_exact_action) {
1997
if (failing()) stop();
1998
if (stopped()) return; // trap reachable?
1999
2000
// Note: If ProfileTraps is true, and if a deopt. actually
2001
// occurs here, the runtime will make sure an MDO exists. There is
2002
// no need to call method()->ensure_method_data() at this point.
2003
2004
// Set the stack pointer to the right value for reexecution:
2005
set_sp(reexecute_sp());
2006
2007
#ifdef ASSERT
2008
if (!must_throw) {
2009
// Make sure the stack has at least enough depth to execute
2010
// the current bytecode.
2011
int inputs, ignored_depth;
2012
if (compute_stack_effects(inputs, ignored_depth)) {
2013
assert(sp() >= inputs, err_msg_res("must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
2014
Bytecodes::name(java_bc()), sp(), inputs));
2015
}
2016
}
2017
#endif
2018
2019
Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2020
Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2021
2022
switch (action) {
2023
case Deoptimization::Action_maybe_recompile:
2024
case Deoptimization::Action_reinterpret:
2025
// Temporary fix for 6529811 to allow virtual calls to be sure they
2026
// get the chance to go from mono->bi->mega
2027
if (!keep_exact_action &&
2028
Deoptimization::trap_request_index(trap_request) < 0 &&
2029
too_many_recompiles(reason)) {
2030
// This BCI is causing too many recompilations.
2031
if (C->log() != NULL) {
2032
C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2033
Deoptimization::trap_reason_name(reason),
2034
Deoptimization::trap_action_name(action));
2035
}
2036
action = Deoptimization::Action_none;
2037
trap_request = Deoptimization::make_trap_request(reason, action);
2038
} else {
2039
C->set_trap_can_recompile(true);
2040
}
2041
break;
2042
case Deoptimization::Action_make_not_entrant:
2043
C->set_trap_can_recompile(true);
2044
break;
2045
#ifdef ASSERT
2046
case Deoptimization::Action_none:
2047
case Deoptimization::Action_make_not_compilable:
2048
break;
2049
default:
2050
fatal(err_msg_res("unknown action %d: %s", action, Deoptimization::trap_action_name(action)));
2051
break;
2052
#endif
2053
}
2054
2055
if (TraceOptoParse) {
2056
char buf[100];
2057
tty->print_cr("Uncommon trap %s at bci:%d",
2058
Deoptimization::format_trap_request(buf, sizeof(buf),
2059
trap_request), bci());
2060
}
2061
2062
CompileLog* log = C->log();
2063
if (log != NULL) {
2064
int kid = (klass == NULL)? -1: log->identify(klass);
2065
log->begin_elem("uncommon_trap bci='%d'", bci());
2066
char buf[100];
2067
log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2068
trap_request));
2069
if (kid >= 0) log->print(" klass='%d'", kid);
2070
if (comment != NULL) log->print(" comment='%s'", comment);
2071
log->end_elem();
2072
}
2073
2074
// Make sure any guarding test views this path as very unlikely
2075
Node *i0 = control()->in(0);
2076
if (i0 != NULL && i0->is_If()) { // Found a guarding if test?
2077
IfNode *iff = i0->as_If();
2078
float f = iff->_prob; // Get prob
2079
if (control()->Opcode() == Op_IfTrue) {
2080
if (f > PROB_UNLIKELY_MAG(4))
2081
iff->_prob = PROB_MIN;
2082
} else {
2083
if (f < PROB_LIKELY_MAG(4))
2084
iff->_prob = PROB_MAX;
2085
}
2086
}
2087
2088
// Clear out dead values from the debug info.
2089
kill_dead_locals();
2090
2091
// Now insert the uncommon trap subroutine call
2092
address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2093
const TypePtr* no_memory_effects = NULL;
2094
// Pass the index of the class to be loaded
2095
Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2096
(must_throw ? RC_MUST_THROW : 0),
2097
OptoRuntime::uncommon_trap_Type(),
2098
call_addr, "uncommon_trap", no_memory_effects,
2099
intcon(trap_request));
2100
assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2101
"must extract request correctly from the graph");
2102
assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2103
2104
call->set_req(TypeFunc::ReturnAdr, returnadr());
2105
// The debug info is the only real input to this call.
2106
2107
// Halt-and-catch fire here. The above call should never return!
2108
HaltNode* halt = new(C) HaltNode(control(), frameptr());
2109
_gvn.set_type_bottom(halt);
2110
root()->add_req(halt);
2111
2112
stop_and_kill_map();
2113
}
2114
2115
2116
//--------------------------just_allocated_object------------------------------
2117
// Report the object that was just allocated.
2118
// It must be the case that there are no intervening safepoints.
2119
// We use this to determine if an object is so "fresh" that
2120
// it does not require card marks.
2121
Node* GraphKit::just_allocated_object(Node* current_control) {
2122
if (C->recent_alloc_ctl() == current_control)
2123
return C->recent_alloc_obj();
2124
return NULL;
2125
}
2126
2127
2128
void GraphKit::round_double_arguments(ciMethod* dest_method) {
2129
// (Note: TypeFunc::make has a cache that makes this fast.)
2130
const TypeFunc* tf = TypeFunc::make(dest_method);
2131
int nargs = tf->_domain->_cnt - TypeFunc::Parms;
2132
for (int j = 0; j < nargs; j++) {
2133
const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
2134
if( targ->basic_type() == T_DOUBLE ) {
2135
// If any parameters are doubles, they must be rounded before
2136
// the call, dstore_rounding does gvn.transform
2137
Node *arg = argument(j);
2138
arg = dstore_rounding(arg);
2139
set_argument(j, arg);
2140
}
2141
}
2142
}
2143
2144
/**
2145
* Record profiling data exact_kls for Node n with the type system so
2146
* that it can propagate it (speculation)
2147
*
2148
* @param n node that the type applies to
2149
* @param exact_kls type from profiling
2150
*
2151
* @return node with improved type
2152
*/
2153
Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls) {
2154
const Type* current_type = _gvn.type(n);
2155
assert(UseTypeSpeculation, "type speculation must be on");
2156
2157
const TypeOopPtr* speculative = current_type->speculative();
2158
2159
if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2160
const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls);
2161
const TypeOopPtr* xtype = tklass->as_instance_type();
2162
assert(xtype->klass_is_exact(), "Should be exact");
2163
// record the new speculative type's depth
2164
speculative = xtype->with_inline_depth(jvms()->depth());
2165
}
2166
2167
if (speculative != current_type->speculative()) {
2168
// Build a type with a speculative type (what we think we know
2169
// about the type but will need a guard when we use it)
2170
const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2171
// We're changing the type, we need a new CheckCast node to carry
2172
// the new type. The new type depends on the control: what
2173
// profiling tells us is only valid from here as far as we can
2174
// tell.
2175
Node* cast = new(C) CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2176
cast = _gvn.transform(cast);
2177
replace_in_map(n, cast);
2178
n = cast;
2179
}
2180
2181
return n;
2182
}
2183
2184
/**
2185
* Record profiling data from receiver profiling at an invoke with the
2186
* type system so that it can propagate it (speculation)
2187
*
2188
* @param n receiver node
2189
*
2190
* @return node with improved type
2191
*/
2192
Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2193
if (!UseTypeSpeculation) {
2194
return n;
2195
}
2196
ciKlass* exact_kls = profile_has_unique_klass();
2197
return record_profile_for_speculation(n, exact_kls);
2198
}
2199
2200
/**
2201
* Record profiling data from argument profiling at an invoke with the
2202
* type system so that it can propagate it (speculation)
2203
*
2204
* @param dest_method target method for the call
2205
* @param bc what invoke bytecode is this?
2206
*/
2207
void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2208
if (!UseTypeSpeculation) {
2209
return;
2210
}
2211
const TypeFunc* tf = TypeFunc::make(dest_method);
2212
int nargs = tf->_domain->_cnt - TypeFunc::Parms;
2213
int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2214
for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2215
const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
2216
if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) {
2217
ciKlass* better_type = method()->argument_profiled_type(bci(), i);
2218
if (better_type != NULL) {
2219
record_profile_for_speculation(argument(j), better_type);
2220
}
2221
i++;
2222
}
2223
}
2224
}
2225
2226
/**
2227
* Record profiling data from parameter profiling at an invoke with
2228
* the type system so that it can propagate it (speculation)
2229
*/
2230
void GraphKit::record_profiled_parameters_for_speculation() {
2231
if (!UseTypeSpeculation) {
2232
return;
2233
}
2234
for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2235
if (_gvn.type(local(i))->isa_oopptr()) {
2236
ciKlass* better_type = method()->parameter_profiled_type(j);
2237
if (better_type != NULL) {
2238
record_profile_for_speculation(local(i), better_type);
2239
}
2240
j++;
2241
}
2242
}
2243
}
2244
2245
void GraphKit::round_double_result(ciMethod* dest_method) {
2246
// A non-strict method may return a double value which has an extended
2247
// exponent, but this must not be visible in a caller which is 'strict'
2248
// If a strict caller invokes a non-strict callee, round a double result
2249
2250
BasicType result_type = dest_method->return_type()->basic_type();
2251
assert( method() != NULL, "must have caller context");
2252
if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
2253
// Destination method's return value is on top of stack
2254
// dstore_rounding() does gvn.transform
2255
Node *result = pop_pair();
2256
result = dstore_rounding(result);
2257
push_pair(result);
2258
}
2259
}
2260
2261
// rounding for strict float precision conformance
2262
Node* GraphKit::precision_rounding(Node* n) {
2263
return UseStrictFP && _method->flags().is_strict()
2264
&& UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2265
? _gvn.transform( new (C) RoundFloatNode(0, n) )
2266
: n;
2267
}
2268
2269
// rounding for strict double precision conformance
2270
Node* GraphKit::dprecision_rounding(Node *n) {
2271
return UseStrictFP && _method->flags().is_strict()
2272
&& UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2273
? _gvn.transform( new (C) RoundDoubleNode(0, n) )
2274
: n;
2275
}
2276
2277
// rounding for non-strict double stores
2278
Node* GraphKit::dstore_rounding(Node* n) {
2279
return Matcher::strict_fp_requires_explicit_rounding
2280
&& UseSSE <= 1
2281
? _gvn.transform( new (C) RoundDoubleNode(0, n) )
2282
: n;
2283
}
2284
2285
//=============================================================================
2286
// Generate a fast path/slow path idiom. Graph looks like:
2287
// [foo] indicates that 'foo' is a parameter
2288
//
2289
// [in] NULL
2290
// \ /
2291
// CmpP
2292
// Bool ne
2293
// If
2294
// / \
2295
// True False-<2>
2296
// / |
2297
// / cast_not_null
2298
// Load | | ^
2299
// [fast_test] | |
2300
// gvn to opt_test | |
2301
// / \ | <1>
2302
// True False |
2303
// | \\ |
2304
// [slow_call] \[fast_result]
2305
// Ctl Val \ \
2306
// | \ \
2307
// Catch <1> \ \
2308
// / \ ^ \ \
2309
// Ex No_Ex | \ \
2310
// | \ \ | \ <2> \
2311
// ... \ [slow_res] | | \ [null_result]
2312
// \ \--+--+--- | |
2313
// \ | / \ | /
2314
// --------Region Phi
2315
//
2316
//=============================================================================
2317
// Code is structured as a series of driver functions all called 'do_XXX' that
2318
// call a set of helper functions. Helper functions first, then drivers.
2319
2320
//------------------------------null_check_oop---------------------------------
2321
// Null check oop. Set null-path control into Region in slot 3.
2322
// Make a cast-not-nullness use the other not-null control. Return cast.
2323
Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2324
bool never_see_null, bool safe_for_replace) {
2325
// Initial NULL check taken path
2326
(*null_control) = top();
2327
Node* cast = null_check_common(value, T_OBJECT, false, null_control);
2328
2329
// Generate uncommon_trap:
2330
if (never_see_null && (*null_control) != top()) {
2331
// If we see an unexpected null at a check-cast we record it and force a
2332
// recompile; the offending check-cast will be compiled to handle NULLs.
2333
// If we see more than one offending BCI, then all checkcasts in the
2334
// method will be compiled to handle NULLs.
2335
PreserveJVMState pjvms(this);
2336
set_control(*null_control);
2337
replace_in_map(value, null());
2338
uncommon_trap(Deoptimization::Reason_null_check,
2339
Deoptimization::Action_make_not_entrant);
2340
(*null_control) = top(); // NULL path is dead
2341
}
2342
if ((*null_control) == top() && safe_for_replace) {
2343
replace_in_map(value, cast);
2344
}
2345
2346
// Cast away null-ness on the result
2347
return cast;
2348
}
2349
2350
//------------------------------opt_iff----------------------------------------
2351
// Optimize the fast-check IfNode. Set the fast-path region slot 2.
2352
// Return slow-path control.
2353
Node* GraphKit::opt_iff(Node* region, Node* iff) {
2354
IfNode *opt_iff = _gvn.transform(iff)->as_If();
2355
2356
// Fast path taken; set region slot 2
2357
Node *fast_taken = _gvn.transform( new (C) IfFalseNode(opt_iff) );
2358
region->init_req(2,fast_taken); // Capture fast-control
2359
2360
// Fast path not-taken, i.e. slow path
2361
Node *slow_taken = _gvn.transform( new (C) IfTrueNode(opt_iff) );
2362
return slow_taken;
2363
}
2364
2365
//-----------------------------make_runtime_call-------------------------------
2366
Node* GraphKit::make_runtime_call(int flags,
2367
const TypeFunc* call_type, address call_addr,
2368
const char* call_name,
2369
const TypePtr* adr_type,
2370
// The following parms are all optional.
2371
// The first NULL ends the list.
2372
Node* parm0, Node* parm1,
2373
Node* parm2, Node* parm3,
2374
Node* parm4, Node* parm5,
2375
Node* parm6, Node* parm7) {
2376
// Slow-path call
2377
bool is_leaf = !(flags & RC_NO_LEAF);
2378
bool has_io = (!is_leaf && !(flags & RC_NO_IO));
2379
if (call_name == NULL) {
2380
assert(!is_leaf, "must supply name for leaf");
2381
call_name = OptoRuntime::stub_name(call_addr);
2382
}
2383
CallNode* call;
2384
if (!is_leaf) {
2385
call = new(C) CallStaticJavaNode(call_type, call_addr, call_name,
2386
bci(), adr_type);
2387
} else if (flags & RC_NO_FP) {
2388
call = new(C) CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2389
} else {
2390
call = new(C) CallLeafNode(call_type, call_addr, call_name, adr_type);
2391
}
2392
2393
// The following is similar to set_edges_for_java_call,
2394
// except that the memory effects of the call are restricted to AliasIdxRaw.
2395
2396
// Slow path call has no side-effects, uses few values
2397
bool wide_in = !(flags & RC_NARROW_MEM);
2398
bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2399
2400
Node* prev_mem = NULL;
2401
if (wide_in) {
2402
prev_mem = set_predefined_input_for_runtime_call(call);
2403
} else {
2404
assert(!wide_out, "narrow in => narrow out");
2405
Node* narrow_mem = memory(adr_type);
2406
prev_mem = set_predefined_input_for_runtime_call(call, narrow_mem);
2407
}
2408
2409
// Hook each parm in order. Stop looking at the first NULL.
2410
if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2411
if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2412
if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2413
if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2414
if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2415
if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2416
if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2417
if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2418
/* close each nested if ===> */ } } } } } } } }
2419
assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2420
2421
if (!is_leaf) {
2422
// Non-leaves can block and take safepoints:
2423
add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2424
}
2425
// Non-leaves can throw exceptions:
2426
if (has_io) {
2427
call->set_req(TypeFunc::I_O, i_o());
2428
}
2429
2430
if (flags & RC_UNCOMMON) {
2431
// Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2432
// (An "if" probability corresponds roughly to an unconditional count.
2433
// Sort of.)
2434
call->set_cnt(PROB_UNLIKELY_MAG(4));
2435
}
2436
2437
Node* c = _gvn.transform(call);
2438
assert(c == call, "cannot disappear");
2439
2440
if (wide_out) {
2441
// Slow path call has full side-effects.
2442
set_predefined_output_for_runtime_call(call);
2443
} else {
2444
// Slow path call has few side-effects, and/or sets few values.
2445
set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2446
}
2447
2448
if (has_io) {
2449
set_i_o(_gvn.transform(new (C) ProjNode(call, TypeFunc::I_O)));
2450
}
2451
return call;
2452
2453
}
2454
2455
//------------------------------merge_memory-----------------------------------
2456
// Merge memory from one path into the current memory state.
2457
void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2458
for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2459
Node* old_slice = mms.force_memory();
2460
Node* new_slice = mms.memory2();
2461
if (old_slice != new_slice) {
2462
PhiNode* phi;
2463
if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2464
if (mms.is_empty()) {
2465
// clone base memory Phi's inputs for this memory slice
2466
assert(old_slice == mms.base_memory(), "sanity");
2467
phi = PhiNode::make(region, NULL, Type::MEMORY, mms.adr_type(C));
2468
_gvn.set_type(phi, Type::MEMORY);
2469
for (uint i = 1; i < phi->req(); i++) {
2470
phi->init_req(i, old_slice->in(i));
2471
}
2472
} else {
2473
phi = old_slice->as_Phi(); // Phi was generated already
2474
}
2475
} else {
2476
phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2477
_gvn.set_type(phi, Type::MEMORY);
2478
}
2479
phi->set_req(new_path, new_slice);
2480
mms.set_memory(phi);
2481
}
2482
}
2483
}
2484
2485
//------------------------------make_slow_call_ex------------------------------
2486
// Make the exception handler hookups for the slow call
2487
void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2488
if (stopped()) return;
2489
2490
// Make a catch node with just two handlers: fall-through and catch-all
2491
Node* i_o = _gvn.transform( new (C) ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2492
Node* catc = _gvn.transform( new (C) CatchNode(control(), i_o, 2) );
2493
Node* norm = _gvn.transform( new (C) CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2494
Node* excp = _gvn.transform( new (C) CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2495
2496
{ PreserveJVMState pjvms(this);
2497
set_control(excp);
2498
set_i_o(i_o);
2499
2500
if (excp != top()) {
2501
if (deoptimize) {
2502
// Deoptimize if an exception is caught. Don't construct exception state in this case.
2503
uncommon_trap(Deoptimization::Reason_unhandled,
2504
Deoptimization::Action_none);
2505
} else {
2506
// Create an exception state also.
2507
// Use an exact type if the caller has specified a specific exception.
2508
const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2509
Node* ex_oop = new (C) CreateExNode(ex_type, control(), i_o);
2510
add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2511
}
2512
}
2513
}
2514
2515
// Get the no-exception control from the CatchNode.
2516
set_control(norm);
2517
}
2518
2519
2520
//-------------------------------gen_subtype_check-----------------------------
2521
// Generate a subtyping check. Takes as input the subtype and supertype.
2522
// Returns 2 values: sets the default control() to the true path and returns
2523
// the false path. Only reads invariant memory; sets no (visible) memory.
2524
// The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2525
// but that's not exposed to the optimizer. This call also doesn't take in an
2526
// Object; if you wish to check an Object you need to load the Object's class
2527
// prior to coming here.
2528
Node* GraphKit::gen_subtype_check(Node* subklass, Node* superklass) {
2529
// Fast check for identical types, perhaps identical constants.
2530
// The types can even be identical non-constants, in cases
2531
// involving Array.newInstance, Object.clone, etc.
2532
if (subklass == superklass)
2533
return top(); // false path is dead; no test needed.
2534
2535
if (_gvn.type(superklass)->singleton()) {
2536
ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2537
ciKlass* subk = _gvn.type(subklass)->is_klassptr()->klass();
2538
2539
// In the common case of an exact superklass, try to fold up the
2540
// test before generating code. You may ask, why not just generate
2541
// the code and then let it fold up? The answer is that the generated
2542
// code will necessarily include null checks, which do not always
2543
// completely fold away. If they are also needless, then they turn
2544
// into a performance loss. Example:
2545
// Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2546
// Here, the type of 'fa' is often exact, so the store check
2547
// of fa[1]=x will fold up, without testing the nullness of x.
2548
switch (static_subtype_check(superk, subk)) {
2549
case SSC_always_false:
2550
{
2551
Node* always_fail = control();
2552
set_control(top());
2553
return always_fail;
2554
}
2555
case SSC_always_true:
2556
return top();
2557
case SSC_easy_test:
2558
{
2559
// Just do a direct pointer compare and be done.
2560
Node* cmp = _gvn.transform( new(C) CmpPNode(subklass, superklass) );
2561
Node* bol = _gvn.transform( new(C) BoolNode(cmp, BoolTest::eq) );
2562
IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2563
set_control( _gvn.transform( new(C) IfTrueNode (iff) ) );
2564
return _gvn.transform( new(C) IfFalseNode(iff) );
2565
}
2566
case SSC_full_test:
2567
break;
2568
default:
2569
ShouldNotReachHere();
2570
}
2571
}
2572
2573
// %%% Possible further optimization: Even if the superklass is not exact,
2574
// if the subklass is the unique subtype of the superklass, the check
2575
// will always succeed. We could leave a dependency behind to ensure this.
2576
2577
// First load the super-klass's check-offset
2578
Node *p1 = basic_plus_adr( superklass, superklass, in_bytes(Klass::super_check_offset_offset()) );
2579
Node *chk_off = _gvn.transform(new (C) LoadINode(NULL, memory(p1), p1, _gvn.type(p1)->is_ptr(),
2580
TypeInt::INT, MemNode::unordered));
2581
int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2582
bool might_be_cache = (find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2583
2584
// Load from the sub-klass's super-class display list, or a 1-word cache of
2585
// the secondary superclass list, or a failing value with a sentinel offset
2586
// if the super-klass is an interface or exceptionally deep in the Java
2587
// hierarchy and we have to scan the secondary superclass list the hard way.
2588
// Worst-case type is a little odd: NULL is allowed as a result (usually
2589
// klass loads can never produce a NULL).
2590
Node *chk_off_X = ConvI2X(chk_off);
2591
Node *p2 = _gvn.transform( new (C) AddPNode(subklass,subklass,chk_off_X) );
2592
// For some types like interfaces the following loadKlass is from a 1-word
2593
// cache which is mutable so can't use immutable memory. Other
2594
// types load from the super-class display table which is immutable.
2595
Node *kmem = might_be_cache ? memory(p2) : immutable_memory();
2596
Node* nkls = _gvn.transform(LoadKlassNode::make(_gvn, NULL, kmem, p2, _gvn.type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL));
2597
2598
// Compile speed common case: ARE a subtype and we canNOT fail
2599
if( superklass == nkls )
2600
return top(); // false path is dead; no test needed.
2601
2602
// See if we get an immediate positive hit. Happens roughly 83% of the
2603
// time. Test to see if the value loaded just previously from the subklass
2604
// is exactly the superklass.
2605
Node *cmp1 = _gvn.transform( new (C) CmpPNode( superklass, nkls ) );
2606
Node *bol1 = _gvn.transform( new (C) BoolNode( cmp1, BoolTest::eq ) );
2607
IfNode *iff1 = create_and_xform_if( control(), bol1, PROB_LIKELY(0.83f), COUNT_UNKNOWN );
2608
Node *iftrue1 = _gvn.transform( new (C) IfTrueNode ( iff1 ) );
2609
set_control( _gvn.transform( new (C) IfFalseNode( iff1 ) ) );
2610
2611
// Compile speed common case: Check for being deterministic right now. If
2612
// chk_off is a constant and not equal to cacheoff then we are NOT a
2613
// subklass. In this case we need exactly the 1 test above and we can
2614
// return those results immediately.
2615
if (!might_be_cache) {
2616
Node* not_subtype_ctrl = control();
2617
set_control(iftrue1); // We need exactly the 1 test above
2618
return not_subtype_ctrl;
2619
}
2620
2621
// Gather the various success & failures here
2622
RegionNode *r_ok_subtype = new (C) RegionNode(4);
2623
record_for_igvn(r_ok_subtype);
2624
RegionNode *r_not_subtype = new (C) RegionNode(3);
2625
record_for_igvn(r_not_subtype);
2626
2627
r_ok_subtype->init_req(1, iftrue1);
2628
2629
// Check for immediate negative hit. Happens roughly 11% of the time (which
2630
// is roughly 63% of the remaining cases). Test to see if the loaded
2631
// check-offset points into the subklass display list or the 1-element
2632
// cache. If it points to the display (and NOT the cache) and the display
2633
// missed then it's not a subtype.
2634
Node *cacheoff = _gvn.intcon(cacheoff_con);
2635
Node *cmp2 = _gvn.transform( new (C) CmpINode( chk_off, cacheoff ) );
2636
Node *bol2 = _gvn.transform( new (C) BoolNode( cmp2, BoolTest::ne ) );
2637
IfNode *iff2 = create_and_xform_if( control(), bol2, PROB_LIKELY(0.63f), COUNT_UNKNOWN );
2638
r_not_subtype->init_req(1, _gvn.transform( new (C) IfTrueNode (iff2) ) );
2639
set_control( _gvn.transform( new (C) IfFalseNode(iff2) ) );
2640
2641
// Check for self. Very rare to get here, but it is taken 1/3 the time.
2642
// No performance impact (too rare) but allows sharing of secondary arrays
2643
// which has some footprint reduction.
2644
Node *cmp3 = _gvn.transform( new (C) CmpPNode( subklass, superklass ) );
2645
Node *bol3 = _gvn.transform( new (C) BoolNode( cmp3, BoolTest::eq ) );
2646
IfNode *iff3 = create_and_xform_if( control(), bol3, PROB_LIKELY(0.36f), COUNT_UNKNOWN );
2647
r_ok_subtype->init_req(2, _gvn.transform( new (C) IfTrueNode ( iff3 ) ) );
2648
set_control( _gvn.transform( new (C) IfFalseNode( iff3 ) ) );
2649
2650
// -- Roads not taken here: --
2651
// We could also have chosen to perform the self-check at the beginning
2652
// of this code sequence, as the assembler does. This would not pay off
2653
// the same way, since the optimizer, unlike the assembler, can perform
2654
// static type analysis to fold away many successful self-checks.
2655
// Non-foldable self checks work better here in second position, because
2656
// the initial primary superclass check subsumes a self-check for most
2657
// types. An exception would be a secondary type like array-of-interface,
2658
// which does not appear in its own primary supertype display.
2659
// Finally, we could have chosen to move the self-check into the
2660
// PartialSubtypeCheckNode, and from there out-of-line in a platform
2661
// dependent manner. But it is worthwhile to have the check here,
2662
// where it can be perhaps be optimized. The cost in code space is
2663
// small (register compare, branch).
2664
2665
// Now do a linear scan of the secondary super-klass array. Again, no real
2666
// performance impact (too rare) but it's gotta be done.
2667
// Since the code is rarely used, there is no penalty for moving it
2668
// out of line, and it can only improve I-cache density.
2669
// The decision to inline or out-of-line this final check is platform
2670
// dependent, and is found in the AD file definition of PartialSubtypeCheck.
2671
Node* psc = _gvn.transform(
2672
new (C) PartialSubtypeCheckNode(control(), subklass, superklass) );
2673
2674
Node *cmp4 = _gvn.transform( new (C) CmpPNode( psc, null() ) );
2675
Node *bol4 = _gvn.transform( new (C) BoolNode( cmp4, BoolTest::ne ) );
2676
IfNode *iff4 = create_and_xform_if( control(), bol4, PROB_FAIR, COUNT_UNKNOWN );
2677
r_not_subtype->init_req(2, _gvn.transform( new (C) IfTrueNode (iff4) ) );
2678
r_ok_subtype ->init_req(3, _gvn.transform( new (C) IfFalseNode(iff4) ) );
2679
2680
// Return false path; set default control to true path.
2681
set_control( _gvn.transform(r_ok_subtype) );
2682
return _gvn.transform(r_not_subtype);
2683
}
2684
2685
//----------------------------static_subtype_check-----------------------------
2686
// Shortcut important common cases when superklass is exact:
2687
// (0) superklass is java.lang.Object (can occur in reflective code)
2688
// (1) subklass is already limited to a subtype of superklass => always ok
2689
// (2) subklass does not overlap with superklass => always fail
2690
// (3) superklass has NO subtypes and we can check with a simple compare.
2691
int GraphKit::static_subtype_check(ciKlass* superk, ciKlass* subk) {
2692
if (StressReflectiveCode) {
2693
return SSC_full_test; // Let caller generate the general case.
2694
}
2695
2696
if (superk == env()->Object_klass()) {
2697
return SSC_always_true; // (0) this test cannot fail
2698
}
2699
2700
ciType* superelem = superk;
2701
if (superelem->is_array_klass())
2702
superelem = superelem->as_array_klass()->base_element_type();
2703
2704
if (!subk->is_interface()) { // cannot trust static interface types yet
2705
if (subk->is_subtype_of(superk)) {
2706
return SSC_always_true; // (1) false path dead; no dynamic test needed
2707
}
2708
if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
2709
!superk->is_subtype_of(subk)) {
2710
return SSC_always_false;
2711
}
2712
}
2713
2714
// If casting to an instance klass, it must have no subtypes
2715
if (superk->is_interface()) {
2716
// Cannot trust interfaces yet.
2717
// %%% S.B. superk->nof_implementors() == 1
2718
} else if (superelem->is_instance_klass()) {
2719
ciInstanceKlass* ik = superelem->as_instance_klass();
2720
if (!ik->has_subklass() && !ik->is_interface()) {
2721
if (!ik->is_final()) {
2722
// Add a dependency if there is a chance of a later subclass.
2723
C->dependencies()->assert_leaf_type(ik);
2724
}
2725
return SSC_easy_test; // (3) caller can do a simple ptr comparison
2726
}
2727
} else {
2728
// A primitive array type has no subtypes.
2729
return SSC_easy_test; // (3) caller can do a simple ptr comparison
2730
}
2731
2732
return SSC_full_test;
2733
}
2734
2735
// Profile-driven exact type check:
2736
Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2737
float prob,
2738
Node* *casted_receiver) {
2739
const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2740
Node* recv_klass = load_object_klass(receiver);
2741
Node* want_klass = makecon(tklass);
2742
Node* cmp = _gvn.transform( new(C) CmpPNode(recv_klass, want_klass) );
2743
Node* bol = _gvn.transform( new(C) BoolNode(cmp, BoolTest::eq) );
2744
IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2745
set_control( _gvn.transform( new(C) IfTrueNode (iff) ));
2746
Node* fail = _gvn.transform( new(C) IfFalseNode(iff) );
2747
2748
const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2749
assert(recv_xtype->klass_is_exact(), "");
2750
2751
// Subsume downstream occurrences of receiver with a cast to
2752
// recv_xtype, since now we know what the type will be.
2753
Node* cast = new(C) CheckCastPPNode(control(), receiver, recv_xtype);
2754
(*casted_receiver) = _gvn.transform(cast);
2755
// (User must make the replace_in_map call.)
2756
2757
return fail;
2758
}
2759
2760
2761
//------------------------------seems_never_null-------------------------------
2762
// Use null_seen information if it is available from the profile.
2763
// If we see an unexpected null at a type check we record it and force a
2764
// recompile; the offending check will be recompiled to handle NULLs.
2765
// If we see several offending BCIs, then all checks in the
2766
// method will be recompiled.
2767
bool GraphKit::seems_never_null(Node* obj, ciProfileData* data) {
2768
if (UncommonNullCast // Cutout for this technique
2769
&& obj != null() // And not the -Xcomp stupid case?
2770
&& !too_many_traps(Deoptimization::Reason_null_check)
2771
) {
2772
if (data == NULL)
2773
// Edge case: no mature data. Be optimistic here.
2774
return true;
2775
// If the profile has not seen a null, assume it won't happen.
2776
assert(java_bc() == Bytecodes::_checkcast ||
2777
java_bc() == Bytecodes::_instanceof ||
2778
java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2779
return !data->as_BitData()->null_seen();
2780
}
2781
return false;
2782
}
2783
2784
//------------------------maybe_cast_profiled_receiver-------------------------
2785
// If the profile has seen exactly one type, narrow to exactly that type.
2786
// Subsequent type checks will always fold up.
2787
Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2788
ciKlass* require_klass,
2789
ciKlass* spec_klass,
2790
bool safe_for_replace) {
2791
if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2792
2793
Deoptimization::DeoptReason reason = spec_klass == NULL ? Deoptimization::Reason_class_check : Deoptimization::Reason_speculate_class_check;
2794
2795
// Make sure we haven't already deoptimized from this tactic.
2796
if (too_many_traps(reason) || too_many_recompiles(reason))
2797
return NULL;
2798
2799
// (No, this isn't a call, but it's enough like a virtual call
2800
// to use the same ciMethod accessor to get the profile info...)
2801
// If we have a speculative type use it instead of profiling (which
2802
// may not help us)
2803
ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
2804
if (exact_kls != NULL) {// no cast failures here
2805
if (require_klass == NULL ||
2806
static_subtype_check(require_klass, exact_kls) == SSC_always_true) {
2807
// If we narrow the type to match what the type profile sees or
2808
// the speculative type, we can then remove the rest of the
2809
// cast.
2810
// This is a win, even if the exact_kls is very specific,
2811
// because downstream operations, such as method calls,
2812
// will often benefit from the sharper type.
2813
Node* exact_obj = not_null_obj; // will get updated in place...
2814
Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2815
&exact_obj);
2816
{ PreserveJVMState pjvms(this);
2817
set_control(slow_ctl);
2818
uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
2819
}
2820
if (safe_for_replace) {
2821
replace_in_map(not_null_obj, exact_obj);
2822
}
2823
return exact_obj;
2824
}
2825
// assert(ssc == SSC_always_true)... except maybe the profile lied to us.
2826
}
2827
2828
return NULL;
2829
}
2830
2831
/**
2832
* Cast obj to type and emit guard unless we had too many traps here
2833
* already
2834
*
2835
* @param obj node being casted
2836
* @param type type to cast the node to
2837
* @param not_null true if we know node cannot be null
2838
*/
2839
Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
2840
ciKlass* type,
2841
bool not_null) {
2842
// type == NULL if profiling tells us this object is always null
2843
if (type != NULL) {
2844
Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
2845
Deoptimization::DeoptReason null_reason = Deoptimization::Reason_null_check;
2846
if (!too_many_traps(null_reason) && !too_many_recompiles(null_reason) &&
2847
!too_many_traps(class_reason) && !too_many_recompiles(class_reason)) {
2848
Node* not_null_obj = NULL;
2849
// not_null is true if we know the object is not null and
2850
// there's no need for a null check
2851
if (!not_null) {
2852
Node* null_ctl = top();
2853
not_null_obj = null_check_oop(obj, &null_ctl, true, true);
2854
assert(null_ctl->is_top(), "no null control here");
2855
} else {
2856
not_null_obj = obj;
2857
}
2858
2859
Node* exact_obj = not_null_obj;
2860
ciKlass* exact_kls = type;
2861
Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2862
&exact_obj);
2863
{
2864
PreserveJVMState pjvms(this);
2865
set_control(slow_ctl);
2866
uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
2867
}
2868
replace_in_map(not_null_obj, exact_obj);
2869
obj = exact_obj;
2870
}
2871
} else {
2872
if (!too_many_traps(Deoptimization::Reason_null_assert) &&
2873
!too_many_recompiles(Deoptimization::Reason_null_assert)) {
2874
Node* exact_obj = null_assert(obj);
2875
replace_in_map(obj, exact_obj);
2876
obj = exact_obj;
2877
}
2878
}
2879
return obj;
2880
}
2881
2882
//-------------------------------gen_instanceof--------------------------------
2883
// Generate an instance-of idiom. Used by both the instance-of bytecode
2884
// and the reflective instance-of call.
2885
Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
2886
kill_dead_locals(); // Benefit all the uncommon traps
2887
assert( !stopped(), "dead parse path should be checked in callers" );
2888
assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2889
"must check for not-null not-dead klass in callers");
2890
2891
// Make the merge point
2892
enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2893
RegionNode* region = new(C) RegionNode(PATH_LIMIT);
2894
Node* phi = new(C) PhiNode(region, TypeInt::BOOL);
2895
C->set_has_split_ifs(true); // Has chance for split-if optimization
2896
2897
ciProfileData* data = NULL;
2898
if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode
2899
data = method()->method_data()->bci_to_data(bci());
2900
}
2901
bool never_see_null = (ProfileDynamicTypes // aggressive use of profile
2902
&& seems_never_null(obj, data));
2903
2904
// Null check; get casted pointer; set region slot 3
2905
Node* null_ctl = top();
2906
Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace);
2907
2908
// If not_null_obj is dead, only null-path is taken
2909
if (stopped()) { // Doing instance-of on a NULL?
2910
set_control(null_ctl);
2911
return intcon(0);
2912
}
2913
region->init_req(_null_path, null_ctl);
2914
phi ->init_req(_null_path, intcon(0)); // Set null path value
2915
if (null_ctl == top()) {
2916
// Do this eagerly, so that pattern matches like is_diamond_phi
2917
// will work even during parsing.
2918
assert(_null_path == PATH_LIMIT-1, "delete last");
2919
region->del_req(_null_path);
2920
phi ->del_req(_null_path);
2921
}
2922
2923
// Do we know the type check always succeed?
2924
bool known_statically = false;
2925
if (_gvn.type(superklass)->singleton()) {
2926
ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2927
ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass();
2928
if (subk != NULL && subk->is_loaded()) {
2929
int static_res = static_subtype_check(superk, subk);
2930
known_statically = (static_res == SSC_always_true || static_res == SSC_always_false);
2931
}
2932
}
2933
2934
if (known_statically && UseTypeSpeculation) {
2935
// If we know the type check always succeeds then we don't use the
2936
// profiling data at this bytecode. Don't lose it, feed it to the
2937
// type system as a speculative type.
2938
not_null_obj = record_profiled_receiver_for_speculation(not_null_obj);
2939
} else {
2940
const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
2941
// We may not have profiling here or it may not help us. If we
2942
// have a speculative type use it to perform an exact cast.
2943
ciKlass* spec_obj_type = obj_type->speculative_type();
2944
if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) {
2945
Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace);
2946
if (stopped()) { // Profile disagrees with this path.
2947
set_control(null_ctl); // Null is the only remaining possibility.
2948
return intcon(0);
2949
}
2950
if (cast_obj != NULL) {
2951
not_null_obj = cast_obj;
2952
}
2953
}
2954
}
2955
2956
// Load the object's klass
2957
Node* obj_klass = load_object_klass(not_null_obj);
2958
2959
// Generate the subtype check
2960
Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2961
2962
// Plug in the success path to the general merge in slot 1.
2963
region->init_req(_obj_path, control());
2964
phi ->init_req(_obj_path, intcon(1));
2965
2966
// Plug in the failing path to the general merge in slot 2.
2967
region->init_req(_fail_path, not_subtype_ctrl);
2968
phi ->init_req(_fail_path, intcon(0));
2969
2970
// Return final merged results
2971
set_control( _gvn.transform(region) );
2972
record_for_igvn(region);
2973
return _gvn.transform(phi);
2974
}
2975
2976
//-------------------------------gen_checkcast---------------------------------
2977
// Generate a checkcast idiom. Used by both the checkcast bytecode and the
2978
// array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
2979
// uncommon-trap paths work. Adjust stack after this call.
2980
// If failure_control is supplied and not null, it is filled in with
2981
// the control edge for the cast failure. Otherwise, an appropriate
2982
// uncommon trap or exception is thrown.
2983
Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
2984
Node* *failure_control) {
2985
kill_dead_locals(); // Benefit all the uncommon traps
2986
const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
2987
const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
2988
2989
// Fast cutout: Check the case that the cast is vacuously true.
2990
// This detects the common cases where the test will short-circuit
2991
// away completely. We do this before we perform the null check,
2992
// because if the test is going to turn into zero code, we don't
2993
// want a residual null check left around. (Causes a slowdown,
2994
// for example, in some objArray manipulations, such as a[i]=a[j].)
2995
if (tk->singleton()) {
2996
const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
2997
if (objtp != NULL && objtp->klass() != NULL) {
2998
switch (static_subtype_check(tk->klass(), objtp->klass())) {
2999
case SSC_always_true:
3000
// If we know the type check always succeed then we don't use
3001
// the profiling data at this bytecode. Don't lose it, feed it
3002
// to the type system as a speculative type.
3003
return record_profiled_receiver_for_speculation(obj);
3004
case SSC_always_false:
3005
// It needs a null check because a null will *pass* the cast check.
3006
// A non-null value will always produce an exception.
3007
return null_assert(obj);
3008
}
3009
}
3010
}
3011
3012
ciProfileData* data = NULL;
3013
bool safe_for_replace = false;
3014
if (failure_control == NULL) { // use MDO in regular case only
3015
assert(java_bc() == Bytecodes::_aastore ||
3016
java_bc() == Bytecodes::_checkcast,
3017
"interpreter profiles type checks only for these BCs");
3018
data = method()->method_data()->bci_to_data(bci());
3019
safe_for_replace = true;
3020
}
3021
3022
// Make the merge point
3023
enum { _obj_path = 1, _null_path, PATH_LIMIT };
3024
RegionNode* region = new (C) RegionNode(PATH_LIMIT);
3025
Node* phi = new (C) PhiNode(region, toop);
3026
C->set_has_split_ifs(true); // Has chance for split-if optimization
3027
3028
// Use null-cast information if it is available
3029
bool never_see_null = ((failure_control == NULL) // regular case only
3030
&& seems_never_null(obj, data));
3031
3032
// Null check; get casted pointer; set region slot 3
3033
Node* null_ctl = top();
3034
Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace);
3035
3036
// If not_null_obj is dead, only null-path is taken
3037
if (stopped()) { // Doing instance-of on a NULL?
3038
set_control(null_ctl);
3039
return null();
3040
}
3041
region->init_req(_null_path, null_ctl);
3042
phi ->init_req(_null_path, null()); // Set null path value
3043
if (null_ctl == top()) {
3044
// Do this eagerly, so that pattern matches like is_diamond_phi
3045
// will work even during parsing.
3046
assert(_null_path == PATH_LIMIT-1, "delete last");
3047
region->del_req(_null_path);
3048
phi ->del_req(_null_path);
3049
}
3050
3051
Node* cast_obj = NULL;
3052
if (tk->klass_is_exact()) {
3053
// The following optimization tries to statically cast the speculative type of the object
3054
// (for example obtained during profiling) to the type of the superklass and then do a
3055
// dynamic check that the type of the object is what we expect. To work correctly
3056
// for checkcast and aastore the type of superklass should be exact.
3057
const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3058
// We may not have profiling here or it may not help us. If we have
3059
// a speculative type use it to perform an exact cast.
3060
ciKlass* spec_obj_type = obj_type->speculative_type();
3061
if (spec_obj_type != NULL ||
3062
(data != NULL &&
3063
// Counter has never been decremented (due to cast failure).
3064
// ...This is a reasonable thing to expect. It is true of
3065
// all casts inserted by javac to implement generic types.
3066
data->as_CounterData()->count() >= 0)) {
3067
cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace);
3068
if (cast_obj != NULL) {
3069
if (failure_control != NULL) // failure is now impossible
3070
(*failure_control) = top();
3071
// adjust the type of the phi to the exact klass:
3072
phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3073
}
3074
}
3075
}
3076
3077
if (cast_obj == NULL) {
3078
// Load the object's klass
3079
Node* obj_klass = load_object_klass(not_null_obj);
3080
3081
// Generate the subtype check
3082
Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
3083
3084
// Plug in success path into the merge
3085
cast_obj = _gvn.transform(new (C) CheckCastPPNode(control(),
3086
not_null_obj, toop));
3087
// Failure path ends in uncommon trap (or may be dead - failure impossible)
3088
if (failure_control == NULL) {
3089
if (not_subtype_ctrl != top()) { // If failure is possible
3090
PreserveJVMState pjvms(this);
3091
set_control(not_subtype_ctrl);
3092
builtin_throw(Deoptimization::Reason_class_check, obj_klass);
3093
}
3094
} else {
3095
(*failure_control) = not_subtype_ctrl;
3096
}
3097
}
3098
3099
region->init_req(_obj_path, control());
3100
phi ->init_req(_obj_path, cast_obj);
3101
3102
// A merge of NULL or Casted-NotNull obj
3103
Node* res = _gvn.transform(phi);
3104
3105
// Note I do NOT always 'replace_in_map(obj,result)' here.
3106
// if( tk->klass()->can_be_primary_super() )
3107
// This means that if I successfully store an Object into an array-of-String
3108
// I 'forget' that the Object is really now known to be a String. I have to
3109
// do this because we don't have true union types for interfaces - if I store
3110
// a Baz into an array-of-Interface and then tell the optimizer it's an
3111
// Interface, I forget that it's also a Baz and cannot do Baz-like field
3112
// references to it. FIX THIS WHEN UNION TYPES APPEAR!
3113
// replace_in_map( obj, res );
3114
3115
// Return final merged results
3116
set_control( _gvn.transform(region) );
3117
record_for_igvn(region);
3118
return res;
3119
}
3120
3121
//------------------------------next_monitor-----------------------------------
3122
// What number should be given to the next monitor?
3123
int GraphKit::next_monitor() {
3124
int current = jvms()->monitor_depth()* C->sync_stack_slots();
3125
int next = current + C->sync_stack_slots();
3126
// Keep the toplevel high water mark current:
3127
if (C->fixed_slots() < next) C->set_fixed_slots(next);
3128
return current;
3129
}
3130
3131
//------------------------------insert_mem_bar---------------------------------
3132
// Memory barrier to avoid floating things around
3133
// The membar serves as a pinch point between both control and all memory slices.
3134
Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3135
MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3136
mb->init_req(TypeFunc::Control, control());
3137
mb->init_req(TypeFunc::Memory, reset_memory());
3138
Node* membar = _gvn.transform(mb);
3139
set_control(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Control)));
3140
set_all_memory_call(membar);
3141
return membar;
3142
}
3143
3144
//-------------------------insert_mem_bar_volatile----------------------------
3145
// Memory barrier to avoid floating things around
3146
// The membar serves as a pinch point between both control and memory(alias_idx).
3147
// If you want to make a pinch point on all memory slices, do not use this
3148
// function (even with AliasIdxBot); use insert_mem_bar() instead.
3149
Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3150
// When Parse::do_put_xxx updates a volatile field, it appends a series
3151
// of MemBarVolatile nodes, one for *each* volatile field alias category.
3152
// The first membar is on the same memory slice as the field store opcode.
3153
// This forces the membar to follow the store. (Bug 6500685 broke this.)
3154
// All the other membars (for other volatile slices, including AliasIdxBot,
3155
// which stands for all unknown volatile slices) are control-dependent
3156
// on the first membar. This prevents later volatile loads or stores
3157
// from sliding up past the just-emitted store.
3158
3159
MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3160
mb->set_req(TypeFunc::Control,control());
3161
if (alias_idx == Compile::AliasIdxBot) {
3162
mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3163
} else {
3164
assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3165
mb->set_req(TypeFunc::Memory, memory(alias_idx));
3166
}
3167
Node* membar = _gvn.transform(mb);
3168
set_control(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Control)));
3169
if (alias_idx == Compile::AliasIdxBot) {
3170
merged_memory()->set_base_memory(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Memory)));
3171
} else {
3172
set_memory(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Memory)),alias_idx);
3173
}
3174
return membar;
3175
}
3176
3177
//------------------------------shared_lock------------------------------------
3178
// Emit locking code.
3179
FastLockNode* GraphKit::shared_lock(Node* obj) {
3180
// bci is either a monitorenter bc or InvocationEntryBci
3181
// %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3182
assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3183
3184
if( !GenerateSynchronizationCode )
3185
return NULL; // Not locking things?
3186
if (stopped()) // Dead monitor?
3187
return NULL;
3188
3189
assert(dead_locals_are_killed(), "should kill locals before sync. point");
3190
3191
// Box the stack location
3192
Node* box = _gvn.transform(new (C) BoxLockNode(next_monitor()));
3193
Node* mem = reset_memory();
3194
3195
FastLockNode * flock = _gvn.transform(new (C) FastLockNode(0, obj, box) )->as_FastLock();
3196
if (UseBiasedLocking && PrintPreciseBiasedLockingStatistics) {
3197
// Create the counters for this fast lock.
3198
flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3199
}
3200
3201
// Create the rtm counters for this fast lock if needed.
3202
flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3203
3204
// Add monitor to debug info for the slow path. If we block inside the
3205
// slow path and de-opt, we need the monitor hanging around
3206
map()->push_monitor( flock );
3207
3208
const TypeFunc *tf = LockNode::lock_type();
3209
LockNode *lock = new (C) LockNode(C, tf);
3210
3211
lock->init_req( TypeFunc::Control, control() );
3212
lock->init_req( TypeFunc::Memory , mem );
3213
lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3214
lock->init_req( TypeFunc::FramePtr, frameptr() );
3215
lock->init_req( TypeFunc::ReturnAdr, top() );
3216
3217
lock->init_req(TypeFunc::Parms + 0, obj);
3218
lock->init_req(TypeFunc::Parms + 1, box);
3219
lock->init_req(TypeFunc::Parms + 2, flock);
3220
add_safepoint_edges(lock);
3221
3222
lock = _gvn.transform( lock )->as_Lock();
3223
3224
// lock has no side-effects, sets few values
3225
set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3226
3227
insert_mem_bar(Op_MemBarAcquireLock);
3228
3229
// Add this to the worklist so that the lock can be eliminated
3230
record_for_igvn(lock);
3231
3232
#ifndef PRODUCT
3233
if (PrintLockStatistics) {
3234
// Update the counter for this lock. Don't bother using an atomic
3235
// operation since we don't require absolute accuracy.
3236
lock->create_lock_counter(map()->jvms());
3237
increment_counter(lock->counter()->addr());
3238
}
3239
#endif
3240
3241
return flock;
3242
}
3243
3244
3245
//------------------------------shared_unlock----------------------------------
3246
// Emit unlocking code.
3247
void GraphKit::shared_unlock(Node* box, Node* obj) {
3248
// bci is either a monitorenter bc or InvocationEntryBci
3249
// %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3250
assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3251
3252
if( !GenerateSynchronizationCode )
3253
return;
3254
if (stopped()) { // Dead monitor?
3255
map()->pop_monitor(); // Kill monitor from debug info
3256
return;
3257
}
3258
3259
// Memory barrier to avoid floating things down past the locked region
3260
insert_mem_bar(Op_MemBarReleaseLock);
3261
3262
const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3263
UnlockNode *unlock = new (C) UnlockNode(C, tf);
3264
#ifdef ASSERT
3265
unlock->set_dbg_jvms(sync_jvms());
3266
#endif
3267
uint raw_idx = Compile::AliasIdxRaw;
3268
unlock->init_req( TypeFunc::Control, control() );
3269
unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3270
unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3271
unlock->init_req( TypeFunc::FramePtr, frameptr() );
3272
unlock->init_req( TypeFunc::ReturnAdr, top() );
3273
3274
unlock->init_req(TypeFunc::Parms + 0, obj);
3275
unlock->init_req(TypeFunc::Parms + 1, box);
3276
unlock = _gvn.transform(unlock)->as_Unlock();
3277
3278
Node* mem = reset_memory();
3279
3280
// unlock has no side-effects, sets few values
3281
set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3282
3283
// Kill monitor from debug info
3284
map()->pop_monitor( );
3285
}
3286
3287
//-------------------------------get_layout_helper-----------------------------
3288
// If the given klass is a constant or known to be an array,
3289
// fetch the constant layout helper value into constant_value
3290
// and return (Node*)NULL. Otherwise, load the non-constant
3291
// layout helper value, and return the node which represents it.
3292
// This two-faced routine is useful because allocation sites
3293
// almost always feature constant types.
3294
Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3295
const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
3296
if (!StressReflectiveCode && inst_klass != NULL) {
3297
ciKlass* klass = inst_klass->klass();
3298
bool xklass = inst_klass->klass_is_exact();
3299
if (xklass || klass->is_array_klass()) {
3300
jint lhelper = klass->layout_helper();
3301
if (lhelper != Klass::_lh_neutral_value) {
3302
constant_value = lhelper;
3303
return (Node*) NULL;
3304
}
3305
}
3306
}
3307
constant_value = Klass::_lh_neutral_value; // put in a known value
3308
Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3309
return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3310
}
3311
3312
// We just put in an allocate/initialize with a big raw-memory effect.
3313
// Hook selected additional alias categories on the initialization.
3314
static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3315
MergeMemNode* init_in_merge,
3316
Node* init_out_raw) {
3317
DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3318
assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3319
3320
Node* prevmem = kit.memory(alias_idx);
3321
init_in_merge->set_memory_at(alias_idx, prevmem);
3322
kit.set_memory(init_out_raw, alias_idx);
3323
}
3324
3325
//---------------------------set_output_for_allocation-------------------------
3326
Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3327
const TypeOopPtr* oop_type,
3328
bool deoptimize_on_exception) {
3329
int rawidx = Compile::AliasIdxRaw;
3330
alloc->set_req( TypeFunc::FramePtr, frameptr() );
3331
add_safepoint_edges(alloc);
3332
Node* allocx = _gvn.transform(alloc);
3333
set_control( _gvn.transform(new (C) ProjNode(allocx, TypeFunc::Control) ) );
3334
// create memory projection for i_o
3335
set_memory ( _gvn.transform( new (C) ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3336
make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3337
3338
// create a memory projection as for the normal control path
3339
Node* malloc = _gvn.transform(new (C) ProjNode(allocx, TypeFunc::Memory));
3340
set_memory(malloc, rawidx);
3341
3342
// a normal slow-call doesn't change i_o, but an allocation does
3343
// we create a separate i_o projection for the normal control path
3344
set_i_o(_gvn.transform( new (C) ProjNode(allocx, TypeFunc::I_O, false) ) );
3345
Node* rawoop = _gvn.transform( new (C) ProjNode(allocx, TypeFunc::Parms) );
3346
3347
// put in an initialization barrier
3348
InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3349
rawoop)->as_Initialize();
3350
assert(alloc->initialization() == init, "2-way macro link must work");
3351
assert(init ->allocation() == alloc, "2-way macro link must work");
3352
{
3353
// Extract memory strands which may participate in the new object's
3354
// initialization, and source them from the new InitializeNode.
3355
// This will allow us to observe initializations when they occur,
3356
// and link them properly (as a group) to the InitializeNode.
3357
assert(init->in(InitializeNode::Memory) == malloc, "");
3358
MergeMemNode* minit_in = MergeMemNode::make(C, malloc);
3359
init->set_req(InitializeNode::Memory, minit_in);
3360
record_for_igvn(minit_in); // fold it up later, if possible
3361
Node* minit_out = memory(rawidx);
3362
assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3363
if (oop_type->isa_aryptr()) {
3364
const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3365
int elemidx = C->get_alias_index(telemref);
3366
hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3367
} else if (oop_type->isa_instptr()) {
3368
ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
3369
for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3370
ciField* field = ik->nonstatic_field_at(i);
3371
if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3372
continue; // do not bother to track really large numbers of fields
3373
// Find (or create) the alias category for this field:
3374
int fieldidx = C->alias_type(field)->index();
3375
hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3376
}
3377
}
3378
}
3379
3380
// Cast raw oop to the real thing...
3381
Node* javaoop = new (C) CheckCastPPNode(control(), rawoop, oop_type);
3382
javaoop = _gvn.transform(javaoop);
3383
C->set_recent_alloc(control(), javaoop);
3384
assert(just_allocated_object(control()) == javaoop, "just allocated");
3385
3386
#ifdef ASSERT
3387
{ // Verify that the AllocateNode::Ideal_allocation recognizers work:
3388
assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3389
"Ideal_allocation works");
3390
assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3391
"Ideal_allocation works");
3392
if (alloc->is_AllocateArray()) {
3393
assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3394
"Ideal_allocation works");
3395
assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3396
"Ideal_allocation works");
3397
} else {
3398
assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3399
}
3400
}
3401
#endif //ASSERT
3402
3403
return javaoop;
3404
}
3405
3406
//---------------------------new_instance--------------------------------------
3407
// This routine takes a klass_node which may be constant (for a static type)
3408
// or may be non-constant (for reflective code). It will work equally well
3409
// for either, and the graph will fold nicely if the optimizer later reduces
3410
// the type to a constant.
3411
// The optional arguments are for specialized use by intrinsics:
3412
// - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3413
// - If 'return_size_val', report the the total object size to the caller.
3414
// - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3415
Node* GraphKit::new_instance(Node* klass_node,
3416
Node* extra_slow_test,
3417
Node* *return_size_val,
3418
bool deoptimize_on_exception) {
3419
// Compute size in doublewords
3420
// The size is always an integral number of doublewords, represented
3421
// as a positive bytewise size stored in the klass's layout_helper.
3422
// The layout_helper also encodes (in a low bit) the need for a slow path.
3423
jint layout_con = Klass::_lh_neutral_value;
3424
Node* layout_val = get_layout_helper(klass_node, layout_con);
3425
int layout_is_con = (layout_val == NULL);
3426
3427
if (extra_slow_test == NULL) extra_slow_test = intcon(0);
3428
// Generate the initial go-slow test. It's either ALWAYS (return a
3429
// Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3430
// case) a computed value derived from the layout_helper.
3431
Node* initial_slow_test = NULL;
3432
if (layout_is_con) {
3433
assert(!StressReflectiveCode, "stress mode does not use these paths");
3434
bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3435
initial_slow_test = must_go_slow? intcon(1): extra_slow_test;
3436
3437
} else { // reflective case
3438
// This reflective path is used by Unsafe.allocateInstance.
3439
// (It may be stress-tested by specifying StressReflectiveCode.)
3440
// Basically, we want to get into the VM is there's an illegal argument.
3441
Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3442
initial_slow_test = _gvn.transform( new (C) AndINode(layout_val, bit) );
3443
if (extra_slow_test != intcon(0)) {
3444
initial_slow_test = _gvn.transform( new (C) OrINode(initial_slow_test, extra_slow_test) );
3445
}
3446
// (Macro-expander will further convert this to a Bool, if necessary.)
3447
}
3448
3449
// Find the size in bytes. This is easy; it's the layout_helper.
3450
// The size value must be valid even if the slow path is taken.
3451
Node* size = NULL;
3452
if (layout_is_con) {
3453
size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3454
} else { // reflective case
3455
// This reflective path is used by clone and Unsafe.allocateInstance.
3456
size = ConvI2X(layout_val);
3457
3458
// Clear the low bits to extract layout_helper_size_in_bytes:
3459
assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3460
Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3461
size = _gvn.transform( new (C) AndXNode(size, mask) );
3462
}
3463
if (return_size_val != NULL) {
3464
(*return_size_val) = size;
3465
}
3466
3467
// This is a precise notnull oop of the klass.
3468
// (Actually, it need not be precise if this is a reflective allocation.)
3469
// It's what we cast the result to.
3470
const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3471
if (!tklass) tklass = TypeKlassPtr::OBJECT;
3472
const TypeOopPtr* oop_type = tklass->as_instance_type();
3473
3474
// Now generate allocation code
3475
3476
// The entire memory state is needed for slow path of the allocation
3477
// since GC and deoptimization can happened.
3478
Node *mem = reset_memory();
3479
set_all_memory(mem); // Create new memory state
3480
3481
AllocateNode* alloc
3482
= new (C) AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3483
control(), mem, i_o(),
3484
size, klass_node,
3485
initial_slow_test);
3486
3487
return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3488
}
3489
3490
//-------------------------------new_array-------------------------------------
3491
// helper for both newarray and anewarray
3492
// The 'length' parameter is (obviously) the length of the array.
3493
// See comments on new_instance for the meaning of the other arguments.
3494
Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
3495
Node* length, // number of array elements
3496
int nargs, // number of arguments to push back for uncommon trap
3497
Node* *return_size_val,
3498
bool deoptimize_on_exception) {
3499
jint layout_con = Klass::_lh_neutral_value;
3500
Node* layout_val = get_layout_helper(klass_node, layout_con);
3501
int layout_is_con = (layout_val == NULL);
3502
3503
if (!layout_is_con && !StressReflectiveCode &&
3504
!too_many_traps(Deoptimization::Reason_class_check)) {
3505
// This is a reflective array creation site.
3506
// Optimistically assume that it is a subtype of Object[],
3507
// so that we can fold up all the address arithmetic.
3508
layout_con = Klass::array_layout_helper(T_OBJECT);
3509
Node* cmp_lh = _gvn.transform( new(C) CmpINode(layout_val, intcon(layout_con)) );
3510
Node* bol_lh = _gvn.transform( new(C) BoolNode(cmp_lh, BoolTest::eq) );
3511
{ BuildCutout unless(this, bol_lh, PROB_MAX);
3512
inc_sp(nargs);
3513
uncommon_trap(Deoptimization::Reason_class_check,
3514
Deoptimization::Action_maybe_recompile);
3515
}
3516
layout_val = NULL;
3517
layout_is_con = true;
3518
}
3519
3520
// Generate the initial go-slow test. Make sure we do not overflow
3521
// if length is huge (near 2Gig) or negative! We do not need
3522
// exact double-words here, just a close approximation of needed
3523
// double-words. We can't add any offset or rounding bits, lest we
3524
// take a size -1 of bytes and make it positive. Use an unsigned
3525
// compare, so negative sizes look hugely positive.
3526
int fast_size_limit = FastAllocateSizeLimit;
3527
if (layout_is_con) {
3528
assert(!StressReflectiveCode, "stress mode does not use these paths");
3529
// Increase the size limit if we have exact knowledge of array type.
3530
int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3531
fast_size_limit <<= (LogBytesPerLong - log2_esize);
3532
}
3533
3534
Node* initial_slow_cmp = _gvn.transform( new (C) CmpUNode( length, intcon( fast_size_limit ) ) );
3535
Node* initial_slow_test = _gvn.transform( new (C) BoolNode( initial_slow_cmp, BoolTest::gt ) );
3536
3537
// --- Size Computation ---
3538
// array_size = round_to_heap(array_header + (length << elem_shift));
3539
// where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes)
3540
// and round_to(x, y) == ((x + y-1) & ~(y-1))
3541
// The rounding mask is strength-reduced, if possible.
3542
int round_mask = MinObjAlignmentInBytes - 1;
3543
Node* header_size = NULL;
3544
int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3545
// (T_BYTE has the weakest alignment and size restrictions...)
3546
if (layout_is_con) {
3547
int hsize = Klass::layout_helper_header_size(layout_con);
3548
int eshift = Klass::layout_helper_log2_element_size(layout_con);
3549
BasicType etype = Klass::layout_helper_element_type(layout_con);
3550
if ((round_mask & ~right_n_bits(eshift)) == 0)
3551
round_mask = 0; // strength-reduce it if it goes away completely
3552
assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3553
assert(header_size_min <= hsize, "generic minimum is smallest");
3554
header_size_min = hsize;
3555
header_size = intcon(hsize + round_mask);
3556
} else {
3557
Node* hss = intcon(Klass::_lh_header_size_shift);
3558
Node* hsm = intcon(Klass::_lh_header_size_mask);
3559
Node* hsize = _gvn.transform( new(C) URShiftINode(layout_val, hss) );
3560
hsize = _gvn.transform( new(C) AndINode(hsize, hsm) );
3561
Node* mask = intcon(round_mask);
3562
header_size = _gvn.transform( new(C) AddINode(hsize, mask) );
3563
}
3564
3565
Node* elem_shift = NULL;
3566
if (layout_is_con) {
3567
int eshift = Klass::layout_helper_log2_element_size(layout_con);
3568
if (eshift != 0)
3569
elem_shift = intcon(eshift);
3570
} else {
3571
// There is no need to mask or shift this value.
3572
// The semantics of LShiftINode include an implicit mask to 0x1F.
3573
assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3574
elem_shift = layout_val;
3575
}
3576
3577
// Transition to native address size for all offset calculations:
3578
Node* lengthx = ConvI2X(length);
3579
Node* headerx = ConvI2X(header_size);
3580
#ifdef _LP64
3581
{ const TypeInt* tilen = _gvn.find_int_type(length);
3582
if (tilen != NULL && tilen->_lo < 0) {
3583
// Add a manual constraint to a positive range. Cf. array_element_address.
3584
jlong size_max = fast_size_limit;
3585
if (size_max > tilen->_hi) size_max = tilen->_hi;
3586
const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3587
3588
// Only do a narrow I2L conversion if the range check passed.
3589
IfNode* iff = new (C) IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3590
_gvn.transform(iff);
3591
RegionNode* region = new (C) RegionNode(3);
3592
_gvn.set_type(region, Type::CONTROL);
3593
lengthx = new (C) PhiNode(region, TypeLong::LONG);
3594
_gvn.set_type(lengthx, TypeLong::LONG);
3595
3596
// Range check passed. Use ConvI2L node with narrow type.
3597
Node* passed = IfFalse(iff);
3598
region->init_req(1, passed);
3599
// Make I2L conversion control dependent to prevent it from
3600
// floating above the range check during loop optimizations.
3601
lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3602
3603
// Range check failed. Use ConvI2L with wide type because length may be invalid.
3604
region->init_req(2, IfTrue(iff));
3605
lengthx->init_req(2, ConvI2X(length));
3606
3607
set_control(region);
3608
record_for_igvn(region);
3609
record_for_igvn(lengthx);
3610
}
3611
}
3612
#endif
3613
3614
// Combine header size (plus rounding) and body size. Then round down.
3615
// This computation cannot overflow, because it is used only in two
3616
// places, one where the length is sharply limited, and the other
3617
// after a successful allocation.
3618
Node* abody = lengthx;
3619
if (elem_shift != NULL)
3620
abody = _gvn.transform( new(C) LShiftXNode(lengthx, elem_shift) );
3621
Node* size = _gvn.transform( new(C) AddXNode(headerx, abody) );
3622
if (round_mask != 0) {
3623
Node* mask = MakeConX(~round_mask);
3624
size = _gvn.transform( new(C) AndXNode(size, mask) );
3625
}
3626
// else if round_mask == 0, the size computation is self-rounding
3627
3628
if (return_size_val != NULL) {
3629
// This is the size
3630
(*return_size_val) = size;
3631
}
3632
3633
// Now generate allocation code
3634
3635
// The entire memory state is needed for slow path of the allocation
3636
// since GC and deoptimization can happened.
3637
Node *mem = reset_memory();
3638
set_all_memory(mem); // Create new memory state
3639
3640
if (initial_slow_test->is_Bool()) {
3641
// Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3642
initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3643
}
3644
3645
// Create the AllocateArrayNode and its result projections
3646
AllocateArrayNode* alloc
3647
= new (C) AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3648
control(), mem, i_o(),
3649
size, klass_node,
3650
initial_slow_test,
3651
length);
3652
3653
// Cast to correct type. Note that the klass_node may be constant or not,
3654
// and in the latter case the actual array type will be inexact also.
3655
// (This happens via a non-constant argument to inline_native_newArray.)
3656
// In any case, the value of klass_node provides the desired array type.
3657
const TypeInt* length_type = _gvn.find_int_type(length);
3658
const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3659
if (ary_type->isa_aryptr() && length_type != NULL) {
3660
// Try to get a better type than POS for the size
3661
ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3662
}
3663
3664
Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
3665
3666
// Cast length on remaining path to be as narrow as possible
3667
if (map()->find_edge(length) >= 0) {
3668
Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3669
if (ccast != length) {
3670
_gvn.set_type_bottom(ccast);
3671
record_for_igvn(ccast);
3672
replace_in_map(length, ccast);
3673
}
3674
}
3675
3676
return javaoop;
3677
}
3678
3679
// The following "Ideal_foo" functions are placed here because they recognize
3680
// the graph shapes created by the functions immediately above.
3681
3682
//---------------------------Ideal_allocation----------------------------------
3683
// Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3684
AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3685
if (ptr == NULL) { // reduce dumb test in callers
3686
return NULL;
3687
}
3688
3689
#if INCLUDE_ALL_GCS
3690
if (UseShenandoahGC) {
3691
ptr = ShenandoahBarrierSetC2::bsc2()->step_over_gc_barrier(ptr);
3692
}
3693
#endif
3694
if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3695
ptr = ptr->in(1);
3696
if (ptr == NULL) return NULL;
3697
}
3698
// Return NULL for allocations with several casts:
3699
// j.l.reflect.Array.newInstance(jobject, jint)
3700
// Object.clone()
3701
// to keep more precise type from last cast.
3702
if (ptr->is_Proj()) {
3703
Node* allo = ptr->in(0);
3704
if (allo != NULL && allo->is_Allocate()) {
3705
return allo->as_Allocate();
3706
}
3707
}
3708
// Report failure to match.
3709
return NULL;
3710
}
3711
3712
// Fancy version which also strips off an offset (and reports it to caller).
3713
AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3714
intptr_t& offset) {
3715
Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3716
if (base == NULL) return NULL;
3717
return Ideal_allocation(base, phase);
3718
}
3719
3720
// Trace Initialize <- Proj[Parm] <- Allocate
3721
AllocateNode* InitializeNode::allocation() {
3722
Node* rawoop = in(InitializeNode::RawAddress);
3723
if (rawoop->is_Proj()) {
3724
Node* alloc = rawoop->in(0);
3725
if (alloc->is_Allocate()) {
3726
return alloc->as_Allocate();
3727
}
3728
}
3729
return NULL;
3730
}
3731
3732
// Trace Allocate -> Proj[Parm] -> Initialize
3733
InitializeNode* AllocateNode::initialization() {
3734
ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3735
if (rawoop == NULL) return NULL;
3736
for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3737
Node* init = rawoop->fast_out(i);
3738
if (init->is_Initialize()) {
3739
assert(init->as_Initialize()->allocation() == this, "2-way link");
3740
return init->as_Initialize();
3741
}
3742
}
3743
return NULL;
3744
}
3745
3746
//----------------------------- loop predicates ---------------------------
3747
3748
//------------------------------add_predicate_impl----------------------------
3749
void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3750
// Too many traps seen?
3751
if (too_many_traps(reason)) {
3752
#ifdef ASSERT
3753
if (TraceLoopPredicate) {
3754
int tc = C->trap_count(reason);
3755
tty->print("too many traps=%s tcount=%d in ",
3756
Deoptimization::trap_reason_name(reason), tc);
3757
method()->print(); // which method has too many predicate traps
3758
tty->cr();
3759
}
3760
#endif
3761
// We cannot afford to take more traps here,
3762
// do not generate predicate.
3763
return;
3764
}
3765
3766
Node *cont = _gvn.intcon(1);
3767
Node* opq = _gvn.transform(new (C) Opaque1Node(C, cont));
3768
Node *bol = _gvn.transform(new (C) Conv2BNode(opq));
3769
IfNode* iff = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3770
Node* iffalse = _gvn.transform(new (C) IfFalseNode(iff));
3771
C->add_predicate_opaq(opq);
3772
{
3773
PreserveJVMState pjvms(this);
3774
set_control(iffalse);
3775
inc_sp(nargs);
3776
uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3777
}
3778
Node* iftrue = _gvn.transform(new (C) IfTrueNode(iff));
3779
set_control(iftrue);
3780
}
3781
3782
//------------------------------add_predicate---------------------------------
3783
void GraphKit::add_predicate(int nargs) {
3784
if (UseLoopPredicate) {
3785
add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3786
}
3787
// loop's limit check predicate should be near the loop.
3788
if (LoopLimitCheck) {
3789
add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3790
}
3791
}
3792
3793
//----------------------------- store barriers ----------------------------
3794
#define __ ideal.
3795
3796
void GraphKit::sync_kit(IdealKit& ideal) {
3797
set_all_memory(__ merged_memory());
3798
set_i_o(__ i_o());
3799
set_control(__ ctrl());
3800
}
3801
3802
void GraphKit::final_sync(IdealKit& ideal) {
3803
// Final sync IdealKit and graphKit.
3804
sync_kit(ideal);
3805
}
3806
3807
// vanilla/CMS post barrier
3808
// Insert a write-barrier store. This is to let generational GC work; we have
3809
// to flag all oop-stores before the next GC point.
3810
void GraphKit::write_barrier_post(Node* oop_store,
3811
Node* obj,
3812
Node* adr,
3813
uint adr_idx,
3814
Node* val,
3815
bool use_precise) {
3816
// No store check needed if we're storing a NULL or an old object
3817
// (latter case is probably a string constant). The concurrent
3818
// mark sweep garbage collector, however, needs to have all nonNull
3819
// oop updates flagged via card-marks.
3820
if (val != NULL && val->is_Con()) {
3821
// must be either an oop or NULL
3822
const Type* t = val->bottom_type();
3823
if (t == TypePtr::NULL_PTR || t == Type::TOP)
3824
// stores of null never (?) need barriers
3825
return;
3826
}
3827
3828
if (use_ReduceInitialCardMarks()
3829
&& obj == just_allocated_object(control())) {
3830
// We can skip marks on a freshly-allocated object in Eden.
3831
// Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
3832
// That routine informs GC to take appropriate compensating steps,
3833
// upon a slow-path allocation, so as to make this card-mark
3834
// elision safe.
3835
return;
3836
}
3837
3838
if (!use_precise) {
3839
// All card marks for a (non-array) instance are in one place:
3840
adr = obj;
3841
}
3842
// (Else it's an array (or unknown), and we want more precise card marks.)
3843
assert(adr != NULL, "");
3844
3845
IdealKit ideal(this, true);
3846
3847
// Convert the pointer to an int prior to doing math on it
3848
Node* cast = __ CastPX(__ ctrl(), adr);
3849
3850
// Divide by card size
3851
assert(Universe::heap()->barrier_set()->kind() == BarrierSet::CardTableModRef,
3852
"Only one we handle so far.");
3853
Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3854
3855
// Combine card table base and card offset
3856
Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3857
3858
// Get the alias_index for raw card-mark memory
3859
int adr_type = Compile::AliasIdxRaw;
3860
Node* zero = __ ConI(0); // Dirty card value
3861
BasicType bt = T_BYTE;
3862
3863
if (UseCondCardMark) {
3864
// The classic GC reference write barrier is typically implemented
3865
// as a store into the global card mark table. Unfortunately
3866
// unconditional stores can result in false sharing and excessive
3867
// coherence traffic as well as false transactional aborts.
3868
// UseCondCardMark enables MP "polite" conditional card mark
3869
// stores. In theory we could relax the load from ctrl() to
3870
// no_ctrl, but that doesn't buy much latitude.
3871
Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type);
3872
__ if_then(card_val, BoolTest::ne, zero);
3873
}
3874
3875
// Smash zero into card
3876
if( !UseConcMarkSweepGC ) {
3877
#if defined(AARCH64)
3878
__ store(__ ctrl(), card_adr, zero, bt, adr_type, MemNode::unordered);
3879
#else
3880
__ store(__ ctrl(), card_adr, zero, bt, adr_type, MemNode::release);
3881
#endif
3882
} else {
3883
// Specialized path for CM store barrier
3884
__ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3885
}
3886
3887
if (UseCondCardMark) {
3888
__ end_if();
3889
}
3890
3891
// Final sync IdealKit and GraphKit.
3892
final_sync(ideal);
3893
}
3894
3895
// G1 pre/post barriers
3896
void GraphKit::g1_write_barrier_pre(bool do_load,
3897
Node* obj,
3898
Node* adr,
3899
uint alias_idx,
3900
Node* val,
3901
const TypeOopPtr* val_type,
3902
Node* pre_val,
3903
BasicType bt) {
3904
3905
// Some sanity checks
3906
// Note: val is unused in this routine.
3907
3908
if (do_load) {
3909
// We need to generate the load of the previous value
3910
assert(obj != NULL, "must have a base");
3911
assert(adr != NULL, "where are loading from?");
3912
assert(pre_val == NULL, "loaded already?");
3913
assert(val_type != NULL, "need a type");
3914
} else {
3915
// In this case both val_type and alias_idx are unused.
3916
assert(pre_val != NULL, "must be loaded already");
3917
// Nothing to be done if pre_val is null.
3918
if (pre_val->bottom_type() == TypePtr::NULL_PTR) return;
3919
assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here");
3920
}
3921
assert(bt == T_OBJECT, "or we shouldn't be here");
3922
3923
IdealKit ideal(this, true);
3924
3925
Node* tls = __ thread(); // ThreadLocalStorage
3926
3927
Node* no_ctrl = NULL;
3928
Node* no_base = __ top();
3929
Node* zero = __ ConI(0);
3930
Node* zeroX = __ ConX(0);
3931
3932
float likely = PROB_LIKELY(0.999);
3933
float unlikely = PROB_UNLIKELY(0.999);
3934
3935
BasicType active_type = in_bytes(PtrQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
3936
assert(in_bytes(PtrQueue::byte_width_of_active()) == 4 || in_bytes(PtrQueue::byte_width_of_active()) == 1, "flag width");
3937
3938
// Offsets into the thread
3939
const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648
3940
PtrQueue::byte_offset_of_active());
3941
const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656
3942
PtrQueue::byte_offset_of_index());
3943
const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652
3944
PtrQueue::byte_offset_of_buf());
3945
3946
// Now the actual pointers into the thread
3947
Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
3948
Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3949
Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
3950
3951
// Now some of the values
3952
Node* marking;
3953
if (UseShenandoahGC) {
3954
Node* gc_state = __ AddP(no_base, tls, __ ConX(in_bytes(JavaThread::gc_state_offset())));
3955
Node* ld = __ load(__ ctrl(), gc_state, TypeInt::BYTE, T_BYTE, Compile::AliasIdxRaw);
3956
marking = __ AndI(ld, __ ConI(ShenandoahHeap::MARKING));
3957
assert(ShenandoahBarrierC2Support::is_gc_state_load(ld), "Should match the shape");
3958
} else {
3959
assert(UseG1GC, "should be");
3960
marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
3961
}
3962
3963
// if (!marking)
3964
__ if_then(marking, BoolTest::ne, zero, unlikely); {
3965
BasicType index_bt = TypeX_X->basic_type();
3966
assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 PtrQueue::_index with wrong size.");
3967
Node* index = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw);
3968
3969
if (do_load) {
3970
// load original value
3971
// alias_idx correct??
3972
pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx);
3973
}
3974
3975
// if (pre_val != NULL)
3976
__ if_then(pre_val, BoolTest::ne, null()); {
3977
Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3978
3979
// is the queue for this thread full?
3980
__ if_then(index, BoolTest::ne, zeroX, likely); {
3981
3982
// decrement the index
3983
Node* next_index = _gvn.transform(new (C) SubXNode(index, __ ConX(sizeof(intptr_t))));
3984
3985
// Now get the buffer location we will log the previous value into and store it
3986
Node *log_addr = __ AddP(no_base, buffer, next_index);
3987
__ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered);
3988
// update the index
3989
__ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered);
3990
3991
} __ else_(); {
3992
3993
// logging buffer is full, call the runtime
3994
const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
3995
__ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls);
3996
} __ end_if(); // (!index)
3997
} __ end_if(); // (pre_val != NULL)
3998
} __ end_if(); // (!marking)
3999
4000
// Final sync IdealKit and GraphKit.
4001
final_sync(ideal);
4002
4003
#if INCLUDE_ALL_GCS
4004
if (UseShenandoahGC && adr != NULL) {
4005
Node* c = control();
4006
Node* call = c->in(1)->in(1)->in(1)->in(0);
4007
assert(call->is_g1_wb_pre_call(), "g1_wb_pre call expected");
4008
call->add_req(adr);
4009
}
4010
#endif
4011
}
4012
4013
//
4014
// Update the card table and add card address to the queue
4015
//
4016
void GraphKit::g1_mark_card(IdealKit& ideal,
4017
Node* card_adr,
4018
Node* oop_store,
4019
uint oop_alias_idx,
4020
Node* index,
4021
Node* index_adr,
4022
Node* buffer,
4023
const TypeFunc* tf) {
4024
4025
Node* zero = __ ConI(0);
4026
Node* zeroX = __ ConX(0);
4027
Node* no_base = __ top();
4028
BasicType card_bt = T_BYTE;
4029
// Smash zero into card. MUST BE ORDERED WRT TO STORE
4030
__ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
4031
4032
// Now do the queue work
4033
__ if_then(index, BoolTest::ne, zeroX); {
4034
4035
Node* next_index = _gvn.transform(new (C) SubXNode(index, __ ConX(sizeof(intptr_t))));
4036
Node* log_addr = __ AddP(no_base, buffer, next_index);
4037
4038
// Order, see storeCM.
4039
__ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
4040
__ store(__ ctrl(), index_adr, next_index, TypeX_X->basic_type(), Compile::AliasIdxRaw, MemNode::unordered);
4041
4042
} __ else_(); {
4043
__ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
4044
} __ end_if();
4045
4046
}
4047
4048
void GraphKit::g1_write_barrier_post(Node* oop_store,
4049
Node* obj,
4050
Node* adr,
4051
uint alias_idx,
4052
Node* val,
4053
BasicType bt,
4054
bool use_precise) {
4055
// If we are writing a NULL then we need no post barrier
4056
4057
if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
4058
// Must be NULL
4059
const Type* t = val->bottom_type();
4060
assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
4061
// No post barrier if writing NULLx
4062
return;
4063
}
4064
4065
if (!use_precise) {
4066
// All card marks for a (non-array) instance are in one place:
4067
adr = obj;
4068
}
4069
// (Else it's an array (or unknown), and we want more precise card marks.)
4070
assert(adr != NULL, "");
4071
4072
IdealKit ideal(this, true);
4073
4074
Node* tls = __ thread(); // ThreadLocalStorage
4075
4076
Node* no_base = __ top();
4077
float likely = PROB_LIKELY(0.999);
4078
float unlikely = PROB_UNLIKELY(0.999);
4079
Node* young_card = __ ConI((jint)G1SATBCardTableModRefBS::g1_young_card_val());
4080
Node* dirty_card = __ ConI((jint)CardTableModRefBS::dirty_card_val());
4081
Node* zeroX = __ ConX(0);
4082
4083
// Get the alias_index for raw card-mark memory
4084
const TypePtr* card_type = TypeRawPtr::BOTTOM;
4085
4086
const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
4087
4088
// Offsets into the thread
4089
const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4090
PtrQueue::byte_offset_of_index());
4091
const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4092
PtrQueue::byte_offset_of_buf());
4093
4094
// Pointers into the thread
4095
4096
Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
4097
Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
4098
4099
// Now some values
4100
// Use ctrl to avoid hoisting these values past a safepoint, which could
4101
// potentially reset these fields in the JavaThread.
4102
Node* index = __ load(__ ctrl(), index_adr, TypeX_X, TypeX_X->basic_type(), Compile::AliasIdxRaw);
4103
Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4104
4105
// Convert the store obj pointer to an int prior to doing math on it
4106
// Must use ctrl to prevent "integerized oop" existing across safepoint
4107
Node* cast = __ CastPX(__ ctrl(), adr);
4108
4109
// Divide pointer by card size
4110
Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
4111
4112
// Combine card table base and card offset
4113
Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
4114
4115
// If we know the value being stored does it cross regions?
4116
4117
if (val != NULL) {
4118
// Does the store cause us to cross regions?
4119
4120
// Should be able to do an unsigned compare of region_size instead of
4121
// and extra shift. Do we have an unsigned compare??
4122
// Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
4123
Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
4124
4125
// if (xor_res == 0) same region so skip
4126
__ if_then(xor_res, BoolTest::ne, zeroX); {
4127
4128
// No barrier if we are storing a NULL
4129
__ if_then(val, BoolTest::ne, null(), unlikely); {
4130
4131
// Ok must mark the card if not already dirty
4132
4133
// load the original value of the card
4134
Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4135
4136
__ if_then(card_val, BoolTest::ne, young_card); {
4137
sync_kit(ideal);
4138
// Use Op_MemBarVolatile to achieve the effect of a StoreLoad barrier.
4139
insert_mem_bar(Op_MemBarVolatile, oop_store);
4140
__ sync_kit(this);
4141
4142
Node* card_val_reload = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4143
__ if_then(card_val_reload, BoolTest::ne, dirty_card); {
4144
g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4145
} __ end_if();
4146
} __ end_if();
4147
} __ end_if();
4148
} __ end_if();
4149
} else {
4150
// Object.clone() instrinsic uses this path.
4151
g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4152
}
4153
4154
// Final sync IdealKit and GraphKit.
4155
final_sync(ideal);
4156
}
4157
#undef __
4158
4159
4160
4161
Node* GraphKit::load_String_offset(Node* ctrl, Node* str) {
4162
if (java_lang_String::has_offset_field()) {
4163
int offset_offset = java_lang_String::offset_offset_in_bytes();
4164
const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4165
false, NULL, 0);
4166
const TypePtr* offset_field_type = string_type->add_offset(offset_offset);
4167
int offset_field_idx = C->get_alias_index(offset_field_type);
4168
return make_load(ctrl,
4169
basic_plus_adr(str, str, offset_offset),
4170
TypeInt::INT, T_INT, offset_field_idx, MemNode::unordered);
4171
} else {
4172
return intcon(0);
4173
}
4174
}
4175
4176
Node* GraphKit::load_String_length(Node* ctrl, Node* str) {
4177
if (java_lang_String::has_count_field()) {
4178
int count_offset = java_lang_String::count_offset_in_bytes();
4179
const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4180
false, NULL, 0);
4181
const TypePtr* count_field_type = string_type->add_offset(count_offset);
4182
int count_field_idx = C->get_alias_index(count_field_type);
4183
return make_load(ctrl,
4184
basic_plus_adr(str, str, count_offset),
4185
TypeInt::INT, T_INT, count_field_idx, MemNode::unordered);
4186
} else {
4187
return load_array_length(load_String_value(ctrl, str));
4188
}
4189
}
4190
4191
Node* GraphKit::load_String_value(Node* ctrl, Node* str) {
4192
int value_offset = java_lang_String::value_offset_in_bytes();
4193
const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4194
false, NULL, 0);
4195
const TypePtr* value_field_type = string_type->add_offset(value_offset);
4196
const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4197
TypeAry::make(TypeInt::CHAR,TypeInt::POS),
4198
ciTypeArrayKlass::make(T_CHAR), true, 0);
4199
int value_field_idx = C->get_alias_index(value_field_type);
4200
Node* load = make_load(ctrl, basic_plus_adr(str, str, value_offset),
4201
value_type, T_OBJECT, value_field_idx, MemNode::unordered);
4202
#if INCLUDE_ALL_GCS
4203
if (UseShenandoahGC) {
4204
load = ShenandoahBarrierSetC2::bsc2()->load_reference_barrier(this, load);
4205
}
4206
#endif
4207
// String.value field is known to be @Stable.
4208
if (UseImplicitStableValues) {
4209
load = cast_array_to_stable(load, value_type);
4210
}
4211
return load;
4212
}
4213
4214
void GraphKit::store_String_offset(Node* ctrl, Node* str, Node* value) {
4215
int offset_offset = java_lang_String::offset_offset_in_bytes();
4216
const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4217
false, NULL, 0);
4218
const TypePtr* offset_field_type = string_type->add_offset(offset_offset);
4219
int offset_field_idx = C->get_alias_index(offset_field_type);
4220
store_to_memory(ctrl, basic_plus_adr(str, offset_offset),
4221
value, T_INT, offset_field_idx, MemNode::unordered);
4222
}
4223
4224
void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) {
4225
int value_offset = java_lang_String::value_offset_in_bytes();
4226
const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4227
false, NULL, 0);
4228
const TypePtr* value_field_type = string_type->add_offset(value_offset);
4229
4230
store_oop_to_object(ctrl, str, basic_plus_adr(str, value_offset), value_field_type,
4231
value, TypeAryPtr::CHARS, T_OBJECT, MemNode::unordered);
4232
}
4233
4234
void GraphKit::store_String_length(Node* ctrl, Node* str, Node* value) {
4235
int count_offset = java_lang_String::count_offset_in_bytes();
4236
const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4237
false, NULL, 0);
4238
const TypePtr* count_field_type = string_type->add_offset(count_offset);
4239
int count_field_idx = C->get_alias_index(count_field_type);
4240
store_to_memory(ctrl, basic_plus_adr(str, count_offset),
4241
value, T_INT, count_field_idx, MemNode::unordered);
4242
}
4243
4244
Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) {
4245
// Reify the property as a CastPP node in Ideal graph to comply with monotonicity
4246
// assumption of CCP analysis.
4247
return _gvn.transform(new(C) CastPPNode(ary, ary_type->cast_to_stable(true)));
4248
}
4249
4250