jdk8-mips64-public/hotspot: src/share/vm/opto/parse1.cpp@fd13a567f179 (annotated)

src/share/vm/opto/parse1.cpp@fd13a567f179 (annotated)

src/share/vm/opto/parse1.cpp

Thu, 24 May 2018 19:26:50 +0800

author: aoqi
date: Thu, 24 May 2018 19:26:50 +0800
changeset 8862: fd13a567f179
parent 8856: ac27a9c85bea
permissions: -rw-r--r--

#7046 C2 supports long branch
Contributed-by: fujie

 /*
  * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #include "precompiled.hpp"
 #include "compiler/compileLog.hpp"
 #include "interpreter/linkResolver.hpp"
 #include "oops/method.hpp"
 #include "opto/addnode.hpp"
 #include "opto/c2compiler.hpp"
 #include "opto/idealGraphPrinter.hpp"
 #include "opto/locknode.hpp"
 #include "opto/memnode.hpp"
 #include "opto/parse.hpp"
 #include "opto/rootnode.hpp"
 #include "opto/runtime.hpp"
 #include "runtime/arguments.hpp"
 #include "runtime/handles.inline.hpp"
 #include "runtime/sharedRuntime.hpp"
 #include "utilities/copy.hpp"
 // Static array so we can figure out which bytecodes stop us from compiling
 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
 // and eventually should be encapsulated in a proper class (gri 8/18/98).
 int nodes_created              = 0;
 int methods_parsed             = 0;
 int methods_seen               = 0;
 int blocks_parsed              = 0;
 int blocks_seen                = 0;
 int explicit_null_checks_inserted = 0;
 int explicit_null_checks_elided   = 0;
 int all_null_checks_found         = 0, implicit_null_checks              = 0;
 int implicit_null_throws          = 0;
 int reclaim_idx  = 0;
 int reclaim_in   = 0;
 int reclaim_node = 0;
 #ifndef PRODUCT
 bool Parse::BytecodeParseHistogram::_initialized = false;
 uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
 uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
 uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
 uint Parse::BytecodeParseHistogram::_new_values       [Bytecodes::number_of_codes];
 #endif
 //------------------------------print_statistics-------------------------------
 #ifndef PRODUCT
 void Parse::print_statistics() {
   tty->print_cr("--- Compiler Statistics ---");
   tty->print("Methods seen: %d  Methods parsed: %d", methods_seen, methods_parsed);
   tty->print("  Nodes created: %d", nodes_created);
   tty->cr();
   if (methods_seen != methods_parsed)
     tty->print_cr("Reasons for parse failures (NOT cumulative):");
   tty->print_cr("Blocks parsed: %d  Blocks seen: %d", blocks_parsed, blocks_seen);
   if( explicit_null_checks_inserted )
     tty->print_cr("%d original NULL checks - %d elided (%2d%%); optimizer leaves %d,", explicit_null_checks_inserted, explicit_null_checks_elided, (100*explicit_null_checks_elided)/explicit_null_checks_inserted, all_null_checks_found);
   if( all_null_checks_found )
     tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
                   (100*implicit_null_checks)/all_null_checks_found);
   if( implicit_null_throws )
     tty->print_cr("%d implicit null exceptions at runtime",
                   implicit_null_throws);
   if( PrintParseStatistics && BytecodeParseHistogram::initialized() ) {
     BytecodeParseHistogram::print();
   }
 }
 #endif
 //------------------------------ON STACK REPLACEMENT---------------------------
 // Construct a node which can be used to get incoming state for
 // on stack replacement.
 Node *Parse::fetch_interpreter_state(int index,
                                      BasicType bt,
                                      Node *local_addrs,
                                      Node *local_addrs_base) {
   Node *mem = memory(Compile::AliasIdxRaw);
   Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
   Node *ctl = control();
   // Very similar to LoadNode::make, except we handle un-aligned longs and
   // doubles on Sparc.  Intel can handle them just fine directly.
   Node *l = NULL;
   switch (bt) {                // Signature is flattened
   case T_INT:     l = new (C) LoadINode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInt::INT,        MemNode::unordered); break;
   case T_FLOAT:   l = new (C) LoadFNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::FLOAT,         MemNode::unordered); break;
   case T_ADDRESS: l = new (C) LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM,  MemNode::unordered); break;
   case T_OBJECT:  l = new (C) LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM, MemNode::unordered); break;
   case T_LONG:
   case T_DOUBLE: {
     // Since arguments are in reverse order, the argument address 'adr'
     // refers to the back half of the long/double.  Recompute adr.
     adr = basic_plus_adr(local_addrs_base, local_addrs, -(index+1)*wordSize);
     if (Matcher::misaligned_doubles_ok) {
       l = (bt == T_DOUBLE)
         ? (Node*)new (C) LoadDNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::DOUBLE, MemNode::unordered)
         : (Node*)new (C) LoadLNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeLong::LONG, MemNode::unordered);
     } else {
       l = (bt == T_DOUBLE)
         ? (Node*)new (C) LoadD_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered)
         : (Node*)new (C) LoadL_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered);
     }
     break;
   }
   default: ShouldNotReachHere();
   }
   return _gvn.transform(l);
 }
 // Helper routine to prevent the interpreter from handing
 // unexpected typestate to an OSR method.
 // The Node l is a value newly dug out of the interpreter frame.
 // The type is the type predicted by ciTypeFlow.  Note that it is
 // not a general type, but can only come from Type::get_typeflow_type.
 // The safepoint is a map which will feed an uncommon trap.
 Node* Parse::check_interpreter_type(Node* l, const Type* type,
                                     SafePointNode* &bad_type_exit) {
   const TypeOopPtr* tp = type->isa_oopptr();
   // TypeFlow may assert null-ness if a type appears unloaded.
   if (type == TypePtr::NULL_PTR ||
       (tp != NULL && !tp->klass()->is_loaded())) {
     // Value must be null, not a real oop.
     Node* chk = _gvn.transform( new (C) CmpPNode(l, null()) );
     Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
     IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
     set_control(_gvn.transform( new (C) IfTrueNode(iff) ));
     Node* bad_type = _gvn.transform( new (C) IfFalseNode(iff) );
     bad_type_exit->control()->add_req(bad_type);
     l = null();
   }
   // Typeflow can also cut off paths from the CFG, based on
   // types which appear unloaded, or call sites which appear unlinked.
   // When paths are cut off, values at later merge points can rise
   // toward more specific classes.  Make sure these specific classes
   // are still in effect.
   if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
     // TypeFlow asserted a specific object type.  Value must have that type.
     Node* bad_type_ctrl = NULL;
     l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
     bad_type_exit->control()->add_req(bad_type_ctrl);
   }
   BasicType bt_l = _gvn.type(l)->basic_type();
   BasicType bt_t = type->basic_type();
   assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
   return l;
 }
 // Helper routine which sets up elements of the initial parser map when
 // performing a parse for on stack replacement.  Add values into map.
 // The only parameter contains the address of a interpreter arguments.
 void Parse::load_interpreter_state(Node* osr_buf) {
   int index;
   int max_locals = jvms()->loc_size();
   int max_stack  = jvms()->stk_size();
   // Mismatch between method and jvms can occur since map briefly held
   // an OSR entry state (which takes up one RawPtr word).
   assert(max_locals == method()->max_locals(), "sanity");
   assert(max_stack  >= method()->max_stack(),  "sanity");
   assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
   assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
   // Find the start block.
   Block* osr_block = start_block();
   assert(osr_block->start() == osr_bci(), "sanity");
   // Set initial BCI.
   set_parse_bci(osr_block->start());
   // Set initial stack depth.
   set_sp(osr_block->start_sp());
   // Check bailouts.  We currently do not perform on stack replacement
   // of loops in catch blocks or loops which branch with a non-empty stack.
   if (sp() != 0) {
     C->record_method_not_compilable("OSR starts with non-empty stack");
     return;
   }
   // Do not OSR inside finally clauses:
   if (osr_block->has_trap_at(osr_block->start())) {
     C->record_method_not_compilable("OSR starts with an immediate trap");
     return;
   }
   // Commute monitors from interpreter frame to compiler frame.
   assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
   int mcnt = osr_block->flow()->monitor_count();
   Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
   for (index = 0; index < mcnt; index++) {
     // Make a BoxLockNode for the monitor.
     Node *box = _gvn.transform(new (C) BoxLockNode(next_monitor()));
     // Displaced headers and locked objects are interleaved in the
     // temp OSR buffer.  We only copy the locked objects out here.
     // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
     Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
     // Try and copy the displaced header to the BoxNode
     Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);
     store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
     // Build a bogus FastLockNode (no code will be generated) and push the
     // monitor into our debug info.
     const FastLockNode *flock = _gvn.transform(new (C) FastLockNode( 0, lock_object, box ))->as_FastLock();
     map()->push_monitor(flock);
     // If the lock is our method synchronization lock, tuck it away in
     // _sync_lock for return and rethrow exit paths.
     if (index == 0 && method()->is_synchronized()) {
       _synch_lock = flock;
     }
   }
   // Use the raw liveness computation to make sure that unexpected
   // values don't propagate into the OSR frame.
   MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
   if (!live_locals.is_valid()) {
     // Degenerate or breakpointed method.
     C->record_method_not_compilable("OSR in empty or breakpointed method");
     return;
   }
   // Extract the needed locals from the interpreter frame.
   Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);
   // find all the locals that the interpreter thinks contain live oops
   const BitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
   for (index = 0; index < max_locals; index++) {
     if (!live_locals.at(index)) {
       continue;
     }
     const Type *type = osr_block->local_type_at(index);
     if (type->isa_oopptr() != NULL) {
       // 6403625: Verify that the interpreter oopMap thinks that the oop is live
       // else we might load a stale oop if the MethodLiveness disagrees with the
       // result of the interpreter. If the interpreter says it is dead we agree
       // by making the value go to top.
       //
       if (!live_oops.at(index)) {
         if (C->log() != NULL) {
           C->log()->elem("OSR_mismatch local_index='%d'",index);
         }
         set_local(index, null());
         // and ignore it for the loads
         continue;
       }
     }
     // Filter out TOP, HALF, and BOTTOM.  (Cf. ensure_phi.)
     if (type == Type::TOP || type == Type::HALF) {
       continue;
     }
     // If the type falls to bottom, then this must be a local that
     // is mixing ints and oops or some such.  Forcing it to top
     // makes it go dead.
     if (type == Type::BOTTOM) {
       continue;
     }
     // Construct code to access the appropriate local.
     BasicType bt = type->basic_type();
     if (type == TypePtr::NULL_PTR) {
       // Ptr types are mixed together with T_ADDRESS but NULL is
       // really for T_OBJECT types so correct it.
       bt = T_OBJECT;
     }
     Node *value = fetch_interpreter_state(index, bt, locals_addr, osr_buf);
     set_local(index, value);
   }
   // Extract the needed stack entries from the interpreter frame.
   for (index = 0; index < sp(); index++) {
     const Type *type = osr_block->stack_type_at(index);
     if (type != Type::TOP) {
       // Currently the compiler bails out when attempting to on stack replace
       // at a bci with a non-empty stack.  We should not reach here.
       ShouldNotReachHere();
     }
   }
   // End the OSR migration
   make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
                     CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
                     "OSR_migration_end", TypeRawPtr::BOTTOM,
                     osr_buf);
   // Now that the interpreter state is loaded, make sure it will match
   // at execution time what the compiler is expecting now:
   SafePointNode* bad_type_exit = clone_map();
   bad_type_exit->set_control(new (C) RegionNode(1));
   assert(osr_block->flow()->jsrs()->size() == 0, "should be no jsrs live at osr point");
   for (index = 0; index < max_locals; index++) {
     if (stopped())  break;
     Node* l = local(index);
     if (l->is_top())  continue;  // nothing here
     const Type *type = osr_block->local_type_at(index);
     if (type->isa_oopptr() != NULL) {
       if (!live_oops.at(index)) {
         // skip type check for dead oops
         continue;
       }
     }
     if (osr_block->flow()->local_type_at(index)->is_return_address()) {
       // In our current system it's illegal for jsr addresses to be
       // live into an OSR entry point because the compiler performs
       // inlining of jsrs.  ciTypeFlow has a bailout that detect this
       // case and aborts the compile if addresses are live into an OSR
       // entry point.  Because of that we can assume that any address
       // locals at the OSR entry point are dead.  Method liveness
       // isn't precise enought to figure out that they are dead in all
       // cases so simply skip checking address locals all
       // together. Any type check is guaranteed to fail since the
       // interpreter type is the result of a load which might have any
       // value and the expected type is a constant.
       continue;
     }
     set_local(index, check_interpreter_type(l, type, bad_type_exit));
   }
   for (index = 0; index < sp(); index++) {
     if (stopped())  break;
     Node* l = stack(index);
     if (l->is_top())  continue;  // nothing here
     const Type *type = osr_block->stack_type_at(index);
     set_stack(index, check_interpreter_type(l, type, bad_type_exit));
   }
   if (bad_type_exit->control()->req() > 1) {
     // Build an uncommon trap here, if any inputs can be unexpected.
     bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
     record_for_igvn(bad_type_exit->control());
     SafePointNode* types_are_good = map();
     set_map(bad_type_exit);
     // The unexpected type happens because a new edge is active
     // in the CFG, which typeflow had previously ignored.
     // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
     // This x will be typed as Integer if notReached is not yet linked.
     // It could also happen due to a problem in ciTypeFlow analysis.
     uncommon_trap(Deoptimization::Reason_constraint,
                   Deoptimization::Action_reinterpret);
     set_map(types_are_good);
   }
 }
 //------------------------------Parse------------------------------------------
 // Main parser constructor.
 Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses)
   : _exits(caller)
 {
   // Init some variables
   _caller = caller;
   _method = parse_method;
   _expected_uses = expected_uses;
   _depth = 1 + (caller->has_method() ? caller->depth() : 0);
   _wrote_final = false;
   _wrote_volatile = false;
   _alloc_with_final = NULL;
   _entry_bci = InvocationEntryBci;
   _tf = NULL;
   _block = NULL;
   _first_return = true;
   _replaced_nodes_for_exceptions = false;
   _new_idx = C->unique();
   debug_only(_block_count = -1);
   debug_only(_blocks = (Block*)-1);
 #ifndef PRODUCT
   if (PrintCompilation || PrintOpto) {
     // Make sure I have an inline tree, so I can print messages about it.
     JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
     InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method);
   }
   _max_switch_depth = 0;
   _est_switch_depth = 0;
 #endif
   _tf = TypeFunc::make(method());
   _iter.reset_to_method(method());
   _flow = method()->get_flow_analysis();
   if (_flow->failing()) {
     C->record_method_not_compilable_all_tiers(_flow->failure_reason());
   }
 #ifndef PRODUCT
   if (_flow->has_irreducible_entry()) {
     C->set_parsed_irreducible_loop(true);
   }
 #endif
   if (_expected_uses <= 0) {
     _prof_factor = 1;
   } else {
     float prof_total = parse_method->interpreter_invocation_count();
     if (prof_total <= _expected_uses) {
       _prof_factor = 1;
     } else {
       _prof_factor = _expected_uses / prof_total;
     }
   }
   CompileLog* log = C->log();
   if (log != NULL) {
     log->begin_head("parse method='%d' uses='%g'",
                     log->identify(parse_method), expected_uses);
     if (depth() == 1 && C->is_osr_compilation()) {
       log->print(" osr_bci='%d'", C->entry_bci());
     }
     log->stamp();
     log->end_head();
   }
   // Accumulate deoptimization counts.
   // (The range_check and store_check counts are checked elsewhere.)
   ciMethodData* md = method()->method_data();
   for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
     uint md_count = md->trap_count(reason);
     if (md_count != 0) {
       if (md_count == md->trap_count_limit())
         md_count += md->overflow_trap_count();
       uint total_count = C->trap_count(reason);
       uint old_count   = total_count;
       total_count += md_count;
       // Saturate the add if it overflows.
       if (total_count < old_count || total_count < md_count)
         total_count = (uint)-1;
       C->set_trap_count(reason, total_count);
       if (log != NULL)
         log->elem("observe trap='%s' count='%d' total='%d'",
                   Deoptimization::trap_reason_name(reason),
                   md_count, total_count);
     }
   }
   // Accumulate total sum of decompilations, also.
   C->set_decompile_count(C->decompile_count() + md->decompile_count());
   _count_invocations = C->do_count_invocations();
   _method_data_update = C->do_method_data_update();
   if (log != NULL && method()->has_exception_handlers()) {
     log->elem("observe that='has_exception_handlers'");
   }
   assert(method()->can_be_compiled(),       "Can not parse this method, cutout earlier");
   assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
   // Always register dependence if JVMTI is enabled, because
   // either breakpoint setting or hotswapping of methods may
   // cause deoptimization.
   if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
     C->dependencies()->assert_evol_method(method());
   }
   methods_seen++;
   // Do some special top-level things.
   if (depth() == 1 && C->is_osr_compilation()) {
     _entry_bci = C->entry_bci();
     _flow = method()->get_osr_flow_analysis(osr_bci());
     if (_flow->failing()) {
       C->record_method_not_compilable(_flow->failure_reason());
 #ifndef PRODUCT
       if (PrintOpto && (Verbose || WizardMode)) {
         tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
         if (Verbose) {
           method()->print();
           method()->print_codes();
           _flow->print();
         }
       }
 #endif
     }
     _tf = C->tf();     // the OSR entry type is different
   }
 #ifdef ASSERT
   if (depth() == 1) {
     assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
     if (C->tf() != tf()) {
       MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
       assert(C->env()->system_dictionary_modification_counter_changed(),
              "Must invalidate if TypeFuncs differ");
     }
   } else {
     assert(!this->is_osr_parse(), "no recursive OSR");
   }
 #endif
   methods_parsed++;
 #ifndef PRODUCT
   // add method size here to guarantee that inlined methods are added too
   if (TimeCompiler)
     _total_bytes_compiled += method()->code_size();
   show_parse_info();
 #endif
   if (failing()) {
     if (log)  log->done("parse");
     return;
   }
   gvn().set_type(root(), root()->bottom_type());
   gvn().transform(top());
   // Import the results of the ciTypeFlow.
   init_blocks();
   // Merge point for all normal exits
   build_exits();
   // Setup the initial JVM state map.
   SafePointNode* entry_map = create_entry_map();
   // Check for bailouts during map initialization
   if (failing() || entry_map == NULL) {
     if (log)  log->done("parse");
     return;
   }
   Node_Notes* caller_nn = C->default_node_notes();
   // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
   if (DebugInlinedCalls || depth() == 1) {
     C->set_default_node_notes(make_node_notes(caller_nn));
   }
   if (is_osr_parse()) {
     Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
     entry_map->set_req(TypeFunc::Parms+0, top());
     set_map(entry_map);
     load_interpreter_state(osr_buf);
   } else {
     set_map(entry_map);
     do_method_entry();
   }
   if (depth() == 1 && !failing()) {
     // Add check to deoptimize the nmethod if RTM state was changed
     rtm_deopt();
   }
   // Check for bailouts during method entry or RTM state check setup.
   if (failing()) {
     if (log)  log->done("parse");
     C->set_default_node_notes(caller_nn);
     return;
   }
   entry_map = map();  // capture any changes performed by method setup code
   assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
   // We begin parsing as if we have just encountered a jump to the
   // method entry.
   Block* entry_block = start_block();
   assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
   set_map_clone(entry_map);
   merge_common(entry_block, entry_block->next_path_num());
 #ifndef PRODUCT
   BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
   set_parse_histogram( parse_histogram_obj );
 #endif
   // Parse all the basic blocks.
   do_all_blocks();
   C->set_default_node_notes(caller_nn);
   // Check for bailouts during conversion to graph
   if (failing()) {
     if (log)  log->done("parse");
     return;
   }
   // Fix up all exiting control flow.
   set_map(entry_map);
   do_exits();
   if (log)  log->done("parse nodes='%d' live='%d' memory='" SIZE_FORMAT "'",
                       C->unique(), C->live_nodes(), C->node_arena()->used());
 }
 //---------------------------do_all_blocks-------------------------------------
 void Parse::do_all_blocks() {
   bool has_irreducible = flow()->has_irreducible_entry();
   // Walk over all blocks in Reverse Post-Order.
   while (true) {
     bool progress = false;
     for (int rpo = 0; rpo < block_count(); rpo++) {
       Block* block = rpo_at(rpo);
       if (block->is_parsed()) continue;
       if (!block->is_merged()) {
         // Dead block, no state reaches this block
         continue;
       }
       // Prepare to parse this block.
       load_state_from(block);
       if (stopped()) {
         // Block is dead.
         continue;
       }
       blocks_parsed++;
       progress = true;
       if (block->is_loop_head() || block->is_handler() || has_irreducible && !block->is_ready()) {
         // Not all preds have been parsed.  We must build phis everywhere.
         // (Note that dead locals do not get phis built, ever.)
         ensure_phis_everywhere();
         if (block->is_SEL_head() &&
             (UseLoopPredicate || LoopLimitCheck)) {
           // Add predicate to single entry (not irreducible) loop head.
           assert(!block->has_merged_backedge(), "only entry paths should be merged for now");
           // Need correct bci for predicate.
           // It is fine to set it here since do_one_block() will set it anyway.
           set_parse_bci(block->start());
           add_predicate();
           // Add new region for back branches.
           int edges = block->pred_count() - block->preds_parsed() + 1; // +1 for original region
           RegionNode *r = new (C) RegionNode(edges+1);
           _gvn.set_type(r, Type::CONTROL);
           record_for_igvn(r);
           r->init_req(edges, control());
           set_control(r);
           // Add new phis.
           ensure_phis_everywhere();
         }
         // Leave behind an undisturbed copy of the map, for future merges.
         set_map(clone_map());
       }
       if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
         // In the absence of irreducible loops, the Region and Phis
         // associated with a merge that doesn't involve a backedge can
         // be simplified now since the RPO parsing order guarantees
         // that any path which was supposed to reach here has already
         // been parsed or must be dead.
         Node* c = control();
         Node* result = _gvn.transform_no_reclaim(control());
         if (c != result && TraceOptoParse) {
           tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
         }
         if (result != top()) {
           record_for_igvn(result);
         }
       }
       // Parse the block.
       do_one_block();
       // Check for bailouts.
       if (failing())  return;
     }
     // with irreducible loops multiple passes might be necessary to parse everything
     if (!has_irreducible || !progress) {
       break;
     }
   }
   blocks_seen += block_count();
 #ifndef PRODUCT
   // Make sure there are no half-processed blocks remaining.
   // Every remaining unprocessed block is dead and may be ignored now.
   for (int rpo = 0; rpo < block_count(); rpo++) {
     Block* block = rpo_at(rpo);
     if (!block->is_parsed()) {
       if (TraceOptoParse) {
         tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
       }
       assert(!block->is_merged(), "no half-processed blocks");
     }
   }
 #endif
 }
 static Node* mask_int_value(Node* v, BasicType bt, PhaseGVN* gvn) {
   Compile* C = gvn->C;
   switch (bt) {
   case T_BYTE:
     v = gvn->transform(new (C) LShiftINode(v, gvn->intcon(24)));
     v = gvn->transform(new (C) RShiftINode(v, gvn->intcon(24)));
     break;
   case T_SHORT:
     v = gvn->transform(new (C) LShiftINode(v, gvn->intcon(16)));
     v = gvn->transform(new (C) RShiftINode(v, gvn->intcon(16)));
     break;
   case T_CHAR:
     v = gvn->transform(new (C) AndINode(v, gvn->intcon(0xFFFF)));
     break;
   case T_BOOLEAN:
     v = gvn->transform(new (C) AndINode(v, gvn->intcon(0x1)));
     break;
   }
   return v;
 }
 //-------------------------------build_exits----------------------------------
 // Build normal and exceptional exit merge points.
 void Parse::build_exits() {
   // make a clone of caller to prevent sharing of side-effects
   _exits.set_map(_exits.clone_map());
   _exits.clean_stack(_exits.sp());
   _exits.sync_jvms();
   RegionNode* region = new (C) RegionNode(1);
   record_for_igvn(region);
   gvn().set_type_bottom(region);
   _exits.set_control(region);
   // Note:  iophi and memphi are not transformed until do_exits.
   Node* iophi  = new (C) PhiNode(region, Type::ABIO);
   Node* memphi = new (C) PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
   gvn().set_type_bottom(iophi);
   gvn().set_type_bottom(memphi);
   _exits.set_i_o(iophi);
   _exits.set_all_memory(memphi);
   // Add a return value to the exit state.  (Do not push it yet.)
   if (tf()->range()->cnt() > TypeFunc::Parms) {
     const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
     if (ret_type->isa_int()) {
       BasicType ret_bt = method()->return_type()->basic_type();
       if (ret_bt == T_BOOLEAN ||
           ret_bt == T_CHAR ||
           ret_bt == T_BYTE ||
           ret_bt == T_SHORT) {
         ret_type = TypeInt::INT;
       }
     }
     // Don't "bind" an unloaded return klass to the ret_phi. If the klass
     // becomes loaded during the subsequent parsing, the loaded and unloaded
     // types will not join when we transform and push in do_exits().
     const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
     if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
       ret_type = TypeOopPtr::BOTTOM;
     }
     int         ret_size = type2size[ret_type->basic_type()];
     Node*       ret_phi  = new (C) PhiNode(region, ret_type);
     gvn().set_type_bottom(ret_phi);
     _exits.ensure_stack(ret_size);
     assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
     assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
     _exits.set_argument(0, ret_phi);  // here is where the parser finds it
     // Note:  ret_phi is not yet pushed, until do_exits.
   }
 }
 //----------------------------build_start_state-------------------------------
 // Construct a state which contains only the incoming arguments from an
 // unknown caller.  The method & bci will be NULL & InvocationEntryBci.
 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
   int        arg_size = tf->domain()->cnt();
   int        max_size = MAX2(arg_size, (int)tf->range()->cnt());
   JVMState*  jvms     = new (this) JVMState(max_size - TypeFunc::Parms);
   SafePointNode* map  = new (this) SafePointNode(max_size, NULL);
   record_for_igvn(map);
   assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
   Node_Notes* old_nn = default_node_notes();
   if (old_nn != NULL && has_method()) {
     Node_Notes* entry_nn = old_nn->clone(this);
     JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
     entry_jvms->set_offsets(0);
     entry_jvms->set_bci(entry_bci());
     entry_nn->set_jvms(entry_jvms);
     set_default_node_notes(entry_nn);
   }
   uint i;
   for (i = 0; i < (uint)arg_size; i++) {
     Node* parm = initial_gvn()->transform(new (this) ParmNode(start, i));
     map->init_req(i, parm);
     // Record all these guys for later GVN.
     record_for_igvn(parm);
   }
   for (; i < map->req(); i++) {
     map->init_req(i, top());
   }
   assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
   set_default_node_notes(old_nn);
   map->set_jvms(jvms);
   jvms->set_map(map);
   return jvms;
 }
 //-----------------------------make_node_notes---------------------------------
 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
   if (caller_nn == NULL)  return NULL;
   Node_Notes* nn = caller_nn->clone(C);
   JVMState* caller_jvms = nn->jvms();
   JVMState* jvms = new (C) JVMState(method(), caller_jvms);
   jvms->set_offsets(0);
   jvms->set_bci(_entry_bci);
   nn->set_jvms(jvms);
   return nn;
 }
 //--------------------------return_values--------------------------------------
 void Compile::return_values(JVMState* jvms) {
   GraphKit kit(jvms);
   Node* ret = new (this) ReturnNode(TypeFunc::Parms,
                              kit.control(),
                              kit.i_o(),
                              kit.reset_memory(),
                              kit.frameptr(),
                              kit.returnadr());
   // Add zero or 1 return values
   int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
   if (ret_size > 0) {
     kit.inc_sp(-ret_size);  // pop the return value(s)
     kit.sync_jvms();
     ret->add_req(kit.argument(0));
     // Note:  The second dummy edge is not needed by a ReturnNode.
   }
   // bind it to root
   root()->add_req(ret);
   record_for_igvn(ret);
   initial_gvn()->transform_no_reclaim(ret);
 }
 //------------------------rethrow_exceptions-----------------------------------
 // Bind all exception states in the list into a single RethrowNode.
 void Compile::rethrow_exceptions(JVMState* jvms) {
   GraphKit kit(jvms);
   if (!kit.has_exceptions())  return;  // nothing to generate
   // Load my combined exception state into the kit, with all phis transformed:
   SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
   Node* ex_oop = kit.use_exception_state(ex_map);
   RethrowNode* exit = new (this) RethrowNode(kit.control(),
                                       kit.i_o(), kit.reset_memory(),
                                       kit.frameptr(), kit.returnadr(),
                                       // like a return but with exception input
                                       ex_oop);
   // bind to root
   root()->add_req(exit);
   record_for_igvn(exit);
   initial_gvn()->transform_no_reclaim(exit);
 }
 //---------------------------do_exceptions-------------------------------------
 // Process exceptions arising from the current bytecode.
 // Send caught exceptions to the proper handler within this method.
 // Unhandled exceptions feed into _exit.
 void Parse::do_exceptions() {
   if (!has_exceptions())  return;
   if (failing()) {
     // Pop them all off and throw them away.
     while (pop_exception_state() != NULL) ;
     return;
   }
   PreserveJVMState pjvms(this, false);
   SafePointNode* ex_map;
   while ((ex_map = pop_exception_state()) != NULL) {
     if (!method()->has_exception_handlers()) {
       // Common case:  Transfer control outward.
       // Doing it this early allows the exceptions to common up
       // even between adjacent method calls.
       throw_to_exit(ex_map);
     } else {
       // Have to look at the exception first.
       assert(stopped(), "catch_inline_exceptions trashes the map");
       catch_inline_exceptions(ex_map);
       stop_and_kill_map();      // we used up this exception state; kill it
     }
   }
   // We now return to our regularly scheduled program:
 }
 //---------------------------throw_to_exit-------------------------------------
 // Merge the given map into an exception exit from this method.
 // The exception exit will handle any unlocking of receiver.
 // The ex_oop must be saved within the ex_map, unlike merge_exception.
 void Parse::throw_to_exit(SafePointNode* ex_map) {
   // Pop the JVMS to (a copy of) the caller.
   GraphKit caller;
   caller.set_map_clone(_caller->map());
   caller.set_bci(_caller->bci());
   caller.set_sp(_caller->sp());
   // Copy out the standard machine state:
   for (uint i = 0; i < TypeFunc::Parms; i++) {
     caller.map()->set_req(i, ex_map->in(i));
   }
   if (ex_map->has_replaced_nodes()) {
     _replaced_nodes_for_exceptions = true;
   }
   caller.map()->transfer_replaced_nodes_from(ex_map, _new_idx);
   // ...and the exception:
   Node*          ex_oop        = saved_ex_oop(ex_map);
   SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
   // Finally, collect the new exception state in my exits:
   _exits.add_exception_state(caller_ex_map);
 }
 //------------------------------do_exits---------------------------------------
 void Parse::do_exits() {
   set_parse_bci(InvocationEntryBci);
   // Now peephole on the return bits
   Node* region = _exits.control();
   _exits.set_control(gvn().transform(region));
   Node* iophi = _exits.i_o();
   _exits.set_i_o(gvn().transform(iophi));
   // On PPC64, also add MemBarRelease for constructors which write
   // volatile fields. As support_IRIW_for_not_multiple_copy_atomic_cpu
   // is set on PPC64, no sync instruction is issued after volatile
   // stores. We want to quarantee the same behaviour as on platforms
   // with total store order, although this is not required by the Java
   // memory model. So as with finals, we add a barrier here.
   if (wrote_final() PPC64_ONLY(|| (wrote_volatile() && method()->is_initializer()))) {
     // This method (which must be a constructor by the rules of Java)
     // wrote a final.  The effects of all initializations must be
     // committed to memory before any code after the constructor
     // publishes the reference to the newly constructor object.
     // Rather than wait for the publication, we simply block the
     // writes here.  Rather than put a barrier on only those writes
     // which are required to complete, we force all writes to complete.
     //
     // "All bets are off" unless the first publication occurs after a
     // normal return from the constructor.  We do not attempt to detect
     // such unusual early publications.  But no barrier is needed on
     // exceptional returns, since they cannot publish normally.
     //
     _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
 #ifndef PRODUCT
     if (PrintOpto && (Verbose || WizardMode)) {
       method()->print_name();
       tty->print_cr(" writes finals and needs a memory barrier");
     }
 #endif
   }
   for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
     // transform each slice of the original memphi:
     mms.set_memory(_gvn.transform(mms.memory()));
   }
   if (tf()->range()->cnt() > TypeFunc::Parms) {
     const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
     Node*       ret_phi  = _gvn.transform( _exits.argument(0) );
     if (!_exits.control()->is_top() && _gvn.type(ret_phi)->empty()) {
       // In case of concurrent class loading, the type we set for the
       // ret_phi in build_exits() may have been too optimistic and the
       // ret_phi may be top now.
       // Otherwise, we've encountered an error and have to mark the method as
       // not compilable. Just using an assertion instead would be dangerous
       // as this could lead to an infinite compile loop in non-debug builds.
       {
         MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
         if (C->env()->system_dictionary_modification_counter_changed()) {
           C->record_failure(C2Compiler::retry_class_loading_during_parsing());
         } else {
           C->record_method_not_compilable("Can't determine return type.");
         }
       }
       return;
     }
     if (ret_type->isa_int()) {
       BasicType ret_bt = method()->return_type()->basic_type();
       ret_phi = mask_int_value(ret_phi, ret_bt, &_gvn);
     }
     _exits.push_node(ret_type->basic_type(), ret_phi);
   }
   // Note:  Logic for creating and optimizing the ReturnNode is in Compile.
   // Unlock along the exceptional paths.
   // This is done late so that we can common up equivalent exceptions
   // (e.g., null checks) arising from multiple points within this method.
   // See GraphKit::add_exception_state, which performs the commoning.
   bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
   // record exit from a method if compiled while Dtrace is turned on.
   if (do_synch || C->env()->dtrace_method_probes() || _replaced_nodes_for_exceptions) {
     // First move the exception list out of _exits:
     GraphKit kit(_exits.transfer_exceptions_into_jvms());
     SafePointNode* normal_map = kit.map();  // keep this guy safe
     // Now re-collect the exceptions into _exits:
     SafePointNode* ex_map;
     while ((ex_map = kit.pop_exception_state()) != NULL) {
       Node* ex_oop = kit.use_exception_state(ex_map);
       // Force the exiting JVM state to have this method at InvocationEntryBci.
       // The exiting JVM state is otherwise a copy of the calling JVMS.
       JVMState* caller = kit.jvms();
       JVMState* ex_jvms = caller->clone_shallow(C);
       ex_jvms->set_map(kit.clone_map());
       ex_jvms->map()->set_jvms(ex_jvms);
       ex_jvms->set_bci(   InvocationEntryBci);
       kit.set_jvms(ex_jvms);
       if (do_synch) {
         // Add on the synchronized-method box/object combo
         kit.map()->push_monitor(_synch_lock);
         // Unlock!
         kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
       }
       if (C->env()->dtrace_method_probes()) {
         kit.make_dtrace_method_exit(method());
       }
       if (_replaced_nodes_for_exceptions) {
         kit.map()->apply_replaced_nodes(_new_idx);
       }
       // Done with exception-path processing.
       ex_map = kit.make_exception_state(ex_oop);
       assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
       // Pop the last vestige of this method:
       ex_map->set_jvms(caller->clone_shallow(C));
       ex_map->jvms()->set_map(ex_map);
       _exits.push_exception_state(ex_map);
     }
     assert(_exits.map() == normal_map, "keep the same return state");
   }
   {
     // Capture very early exceptions (receiver null checks) from caller JVMS
     GraphKit caller(_caller);
     SafePointNode* ex_map;
     while ((ex_map = caller.pop_exception_state()) != NULL) {
       _exits.add_exception_state(ex_map);
     }
   }
   _exits.map()->apply_replaced_nodes(_new_idx);
 }
 //-----------------------------create_entry_map-------------------------------
 // Initialize our parser map to contain the types at method entry.
 // For OSR, the map contains a single RawPtr parameter.
 // Initial monitor locking for sync. methods is performed by do_method_entry.
 SafePointNode* Parse::create_entry_map() {
   // Check for really stupid bail-out cases.
   uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
   if (len >= 32760) {
     C->record_method_not_compilable_all_tiers("too many local variables");
     return NULL;
   }
   // clear current replaced nodes that are of no use from here on (map was cloned in build_exits).
   _caller->map()->delete_replaced_nodes();
   // If this is an inlined method, we may have to do a receiver null check.
   if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
     GraphKit kit(_caller);
     kit.null_check_receiver_before_call(method());
     _caller = kit.transfer_exceptions_into_jvms();
     if (kit.stopped()) {
       _exits.add_exception_states_from(_caller);
       _exits.set_jvms(_caller);
       return NULL;
     }
   }
   assert(method() != NULL, "parser must have a method");
   // Create an initial safepoint to hold JVM state during parsing
   JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
   set_map(new (C) SafePointNode(len, jvms));
   jvms->set_map(map());
   record_for_igvn(map());
   assert(jvms->endoff() == len, "correct jvms sizing");
   SafePointNode* inmap = _caller->map();
   assert(inmap != NULL, "must have inmap");
   // In case of null check on receiver above
   map()->transfer_replaced_nodes_from(inmap, _new_idx);
   uint i;
   // Pass thru the predefined input parameters.
   for (i = 0; i < TypeFunc::Parms; i++) {
     map()->init_req(i, inmap->in(i));
   }
   if (depth() == 1) {
     assert(map()->memory()->Opcode() == Op_Parm, "");
     // Insert the memory aliasing node
     set_all_memory(reset_memory());
   }
   assert(merged_memory(), "");
   // Now add the locals which are initially bound to arguments:
   uint arg_size = tf()->domain()->cnt();
   ensure_stack(arg_size - TypeFunc::Parms);  // OSR methods have funny args
   for (i = TypeFunc::Parms; i < arg_size; i++) {
     map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
   }
   // Clear out the rest of the map (locals and stack)
   for (i = arg_size; i < len; i++) {
     map()->init_req(i, top());
   }
   SafePointNode* entry_map = stop();
   return entry_map;
 }
 //-----------------------------do_method_entry--------------------------------
 // Emit any code needed in the pseudo-block before BCI zero.
 // The main thing to do is lock the receiver of a synchronized method.
 void Parse::do_method_entry() {
   set_parse_bci(InvocationEntryBci); // Pseudo-BCP
   set_sp(0);                      // Java Stack Pointer
   NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
   if (C->env()->dtrace_method_probes()) {
     make_dtrace_method_entry(method());
   }
   // If the method is synchronized, we need to construct a lock node, attach
   // it to the Start node, and pin it there.
   if (method()->is_synchronized()) {
     // Insert a FastLockNode right after the Start which takes as arguments
     // the current thread pointer, the "this" pointer & the address of the
     // stack slot pair used for the lock.  The "this" pointer is a projection
     // off the start node, but the locking spot has to be constructed by
     // creating a ConLNode of 0, and boxing it with a BoxLockNode.  The BoxLockNode
     // becomes the second argument to the FastLockNode call.  The
     // FastLockNode becomes the new control parent to pin it to the start.
     // Setup Object Pointer
     Node *lock_obj = NULL;
     if(method()->is_static()) {
       ciInstance* mirror = _method->holder()->java_mirror();
       const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
       lock_obj = makecon(t_lock);
     } else {                  // Else pass the "this" pointer,
       lock_obj = local(0);    // which is Parm0 from StartNode
     }
     // Clear out dead values from the debug info.
     kill_dead_locals();
     // Build the FastLockNode
     _synch_lock = shared_lock(lock_obj);
   }
   // Feed profiling data for parameters to the type system so it can
   // propagate it as speculative types
   record_profiled_parameters_for_speculation();
   if (depth() == 1) {
     increment_and_test_invocation_counter(Tier2CompileThreshold);
   }
 }
 //------------------------------init_blocks------------------------------------
 // Initialize our parser map to contain the types/monitors at method entry.
 void Parse::init_blocks() {
   // Create the blocks.
   _block_count = flow()->block_count();
   _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
   Copy::zero_to_bytes(_blocks, sizeof(Block)*_block_count);
   int rpo;
   // Initialize the structs.
   for (rpo = 0; rpo < block_count(); rpo++) {
     Block* block = rpo_at(rpo);
     block->init_node(this, rpo);
   }
   // Collect predecessor and successor information.
   for (rpo = 0; rpo < block_count(); rpo++) {
     Block* block = rpo_at(rpo);
     block->init_graph(this);
   }
 }
 //-------------------------------init_node-------------------------------------
 void Parse::Block::init_node(Parse* outer, int rpo) {
   _flow = outer->flow()->rpo_at(rpo);
   _pred_count = 0;
   _preds_parsed = 0;
   _count = 0;
   assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
   assert(!(is_merged() || is_parsed() || is_handler() || has_merged_backedge()), "sanity");
   assert(_live_locals.size() == 0, "sanity");
   // entry point has additional predecessor
   if (flow()->is_start())  _pred_count++;
   assert(flow()->is_start() == (this == outer->start_block()), "");
 }
 //-------------------------------init_graph------------------------------------
 void Parse::Block::init_graph(Parse* outer) {
   // Create the successor list for this parser block.
   GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
   GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
   int ns = tfs->length();
   int ne = tfe->length();
   _num_successors = ns;
   _all_successors = ns+ne;
   _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
   int p = 0;
   for (int i = 0; i < ns+ne; i++) {
     ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
     Block* block2 = outer->rpo_at(tf2->rpo());
     _successors[i] = block2;
     // Accumulate pred info for the other block, too.
     if (i < ns) {
       block2->_pred_count++;
     } else {
       block2->_is_handler = true;
     }
     #ifdef ASSERT
     // A block's successors must be distinguishable by BCI.
     // That is, no bytecode is allowed to branch to two different
     // clones of the same code location.
     for (int j = 0; j < i; j++) {
       Block* block1 = _successors[j];
       if (block1 == block2)  continue;  // duplicates are OK
       assert(block1->start() != block2->start(), "successors have unique bcis");
     }
     #endif
   }
   // Note: We never call next_path_num along exception paths, so they
   // never get processed as "ready".  Also, the input phis of exception
   // handlers get specially processed, so that
 }
 //---------------------------successor_for_bci---------------------------------
 Parse::Block* Parse::Block::successor_for_bci(int bci) {
   for (int i = 0; i < all_successors(); i++) {
     Block* block2 = successor_at(i);
     if (block2->start() == bci)  return block2;
   }
   // We can actually reach here if ciTypeFlow traps out a block
   // due to an unloaded class, and concurrently with compilation the
   // class is then loaded, so that a later phase of the parser is
   // able to see more of the bytecode CFG.  Or, the flow pass and
   // the parser can have a minor difference of opinion about executability
   // of bytecodes.  For example, "obj.field = null" is executable even
   // if the field's type is an unloaded class; the flow pass used to
   // make a trap for such code.
   return NULL;
 }
 //-----------------------------stack_type_at-----------------------------------
 const Type* Parse::Block::stack_type_at(int i) const {
   return get_type(flow()->stack_type_at(i));
 }
 //-----------------------------local_type_at-----------------------------------
 const Type* Parse::Block::local_type_at(int i) const {
   // Make dead locals fall to bottom.
   if (_live_locals.size() == 0) {
     MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
     // This bitmap can be zero length if we saw a breakpoint.
     // In such cases, pretend they are all live.
     ((Block*)this)->_live_locals = live_locals;
   }
   if (_live_locals.size() > 0 && !_live_locals.at(i))
     return Type::BOTTOM;
   return get_type(flow()->local_type_at(i));
 }
 #ifndef PRODUCT
 //----------------------------name_for_bc--------------------------------------
 // helper method for BytecodeParseHistogram
 static const char* name_for_bc(int i) {
   return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
 }
 //----------------------------BytecodeParseHistogram------------------------------------
 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
   _parser   = p;
   _compiler = c;
   if( ! _initialized ) { _initialized = true; reset(); }
 }
 //----------------------------current_count------------------------------------
 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
   switch( bph_type ) {
   case BPH_transforms: { return _parser->gvn().made_progress(); }
   case BPH_values:     { return _parser->gvn().made_new_values(); }
   default: { ShouldNotReachHere(); return 0; }
   }
 }
 //----------------------------initialized--------------------------------------
 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
 //----------------------------reset--------------------------------------------
 void Parse::BytecodeParseHistogram::reset() {
   int i = Bytecodes::number_of_codes;
   while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
 }
 //----------------------------set_initial_state--------------------------------
 // Record info when starting to parse one bytecode
 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
   if( PrintParseStatistics && !_parser->is_osr_parse() ) {
     _initial_bytecode    = bc;
     _initial_node_count  = _compiler->unique();
     _initial_transforms  = current_count(BPH_transforms);
     _initial_values      = current_count(BPH_values);
   }
 }
 //----------------------------record_change--------------------------------
 // Record results of parsing one bytecode
 void Parse::BytecodeParseHistogram::record_change() {
   if( PrintParseStatistics && !_parser->is_osr_parse() ) {
     ++_bytecodes_parsed[_initial_bytecode];
     _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
     _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
     _new_values        [_initial_bytecode] += (current_count(BPH_values)     - _initial_values);
   }
 }
 //----------------------------print--------------------------------------------
 void Parse::BytecodeParseHistogram::print(float cutoff) {
   ResourceMark rm;
   // print profile
   int total  = 0;
   int i      = 0;
   for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
   int abs_sum = 0;
   tty->cr();   //0123456789012345678901234567890123456789012345678901234567890123456789
   tty->print_cr("Histogram of %d parsed bytecodes:", total);
   if( total == 0 ) { return; }
   tty->cr();
   tty->print_cr("absolute:  count of compiled bytecodes of this type");
   tty->print_cr("relative:  percentage contribution to compiled nodes");
   tty->print_cr("nodes   :  Average number of nodes constructed per bytecode");
   tty->print_cr("rnodes  :  Significance towards total nodes constructed, (nodes*relative)");
   tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
   tty->print_cr("values  :  Average number of node values improved per bytecode");
   tty->print_cr("name    :  Bytecode name");
   tty->cr();
   tty->print_cr("  absolute  relative   nodes  rnodes  transforms  values   name");
   tty->print_cr("----------------------------------------------------------------------");
   while (--i > 0) {
     int       abs = _bytecodes_parsed[i];
     float     rel = abs * 100.0F / total;
     float   nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
     float  rnodes = _bytecodes_parsed[i] == 0 ? 0 :  rel * nodes;
     float  xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
     float  values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values       [i])/_bytecodes_parsed[i];
     if (cutoff <= rel) {
       tty->print_cr("%10d  %7.2f%%  %6.1f  %6.2f   %6.1f   %6.1f     %s", abs, rel, nodes, rnodes, xforms, values, name_for_bc(i));
       abs_sum += abs;
     }
   }
   tty->print_cr("----------------------------------------------------------------------");
   float rel_sum = abs_sum * 100.0F / total;
   tty->print_cr("%10d  %7.2f%%    (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
   tty->print_cr("----------------------------------------------------------------------");
   tty->cr();
 }
 #endif
 //----------------------------load_state_from----------------------------------
 // Load block/map/sp.  But not do not touch iter/bci.
 void Parse::load_state_from(Block* block) {
   set_block(block);
   // load the block's JVM state:
   set_map(block->start_map());
   set_sp( block->start_sp());
 }
 //-----------------------------record_state------------------------------------
 void Parse::Block::record_state(Parse* p) {
   assert(!is_merged(), "can only record state once, on 1st inflow");
   assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
   set_start_map(p->stop());
 }
 //------------------------------do_one_block-----------------------------------
 void Parse::do_one_block() {
   if (TraceOptoParse) {
     Block *b = block();
     int ns = b->num_successors();
     int nt = b->all_successors();
     tty->print("Parsing block #%d at bci [%d,%d), successors: ",
                   block()->rpo(), block()->start(), block()->limit());
     for (int i = 0; i < nt; i++) {
       tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
     }
     if (b->is_loop_head()) tty->print("  lphd");
     tty->cr();
   }
   assert(block()->is_merged(), "must be merged before being parsed");
   block()->mark_parsed();
   ++_blocks_parsed;
   // Set iterator to start of block.
   iter().reset_to_bci(block()->start());
   CompileLog* log = C->log();
   // Parse bytecodes
   while (!stopped() && !failing()) {
     iter().next();
     // Learn the current bci from the iterator:
     set_parse_bci(iter().cur_bci());
     if (bci() == block()->limit()) {
       // Do not walk into the next block until directed by do_all_blocks.
       merge(bci());
       break;
     }
     assert(bci() < block()->limit(), "bci still in block");
     if (log != NULL) {
       // Output an optional context marker, to help place actions
       // that occur during parsing of this BC.  If there is no log
       // output until the next context string, this context string
       // will be silently ignored.
       log->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
     }
     if (block()->has_trap_at(bci())) {
       // We must respect the flow pass's traps, because it will refuse
       // to produce successors for trapping blocks.
       int trap_index = block()->flow()->trap_index();
       assert(trap_index != 0, "trap index must be valid");
       uncommon_trap(trap_index);
       break;
     }
     NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
 #ifdef ASSERT
     int pre_bc_sp = sp();
     int inputs, depth;
     bool have_se = !stopped() && compute_stack_effects(inputs, depth);
     assert(!have_se || pre_bc_sp >= inputs, err_msg_res("have enough stack to execute this BC: pre_bc_sp=%d, inputs=%d", pre_bc_sp, inputs));
 #endif //ASSERT
     do_one_bytecode();
     assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
            err_msg_res("incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth));
     do_exceptions();
     NOT_PRODUCT( parse_histogram()->record_change(); );
     if (log != NULL)
       log->clear_context();  // skip marker if nothing was printed
     // Fall into next bytecode.  Each bytecode normally has 1 sequential
     // successor which is typically made ready by visiting this bytecode.
     // If the successor has several predecessors, then it is a merge
     // point, starts a new basic block, and is handled like other basic blocks.
   }
 }
 //------------------------------merge------------------------------------------
 void Parse::set_parse_bci(int bci) {
   set_bci(bci);
   Node_Notes* nn = C->default_node_notes();
   if (nn == NULL)  return;
   // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
   if (!DebugInlinedCalls && depth() > 1) {
     return;
   }
   // Update the JVMS annotation, if present.
   JVMState* jvms = nn->jvms();
   if (jvms != NULL && jvms->bci() != bci) {
     // Update the JVMS.
     jvms = jvms->clone_shallow(C);
     jvms->set_bci(bci);
     nn->set_jvms(jvms);
   }
 }
 //------------------------------merge------------------------------------------
 // Merge the current mapping into the basic block starting at bci
 void Parse::merge(int target_bci) {
   Block* target = successor_for_bci(target_bci);
   if (target == NULL) { handle_missing_successor(target_bci); return; }
   assert(!target->is_ready(), "our arrival must be expected");
   int pnum = target->next_path_num();
   merge_common(target, pnum);
 }
 //-------------------------merge_new_path--------------------------------------
 // Merge the current mapping into the basic block, using a new path
 void Parse::merge_new_path(int target_bci) {
   Block* target = successor_for_bci(target_bci);
   if (target == NULL) { handle_missing_successor(target_bci); return; }
   assert(!target->is_ready(), "new path into frozen graph");
   int pnum = target->add_new_path();
   merge_common(target, pnum);
 }
 //-------------------------merge_exception-------------------------------------
 // Merge the current mapping into the basic block starting at bci
 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
 void Parse::merge_exception(int target_bci) {
   assert(sp() == 1, "must have only the throw exception on the stack");
   Block* target = successor_for_bci(target_bci);
   if (target == NULL) { handle_missing_successor(target_bci); return; }
   assert(target->is_handler(), "exceptions are handled by special blocks");
   int pnum = target->add_new_path();
   merge_common(target, pnum);
 }
 //--------------------handle_missing_successor---------------------------------
 void Parse::handle_missing_successor(int target_bci) {
 #ifndef PRODUCT
   Block* b = block();
   int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
   tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
 #endif
   ShouldNotReachHere();
 }
 //--------------------------merge_common---------------------------------------
 void Parse::merge_common(Parse::Block* target, int pnum) {
   if (TraceOptoParse) {
     tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
   }
   // Zap extra stack slots to top
   assert(sp() == target->start_sp(), "");
   clean_stack(sp());
   if (!target->is_merged()) {   // No prior mapping at this bci
     if (TraceOptoParse) { tty->print(" with empty state");  }
     // If this path is dead, do not bother capturing it as a merge.
     // It is "as if" we had 1 fewer predecessors from the beginning.
     if (stopped()) {
       if (TraceOptoParse)  tty->print_cr(", but path is dead and doesn't count");
       return;
     }
     // Record that a new block has been merged.
     ++_blocks_merged;
     // Make a region if we know there are multiple or unpredictable inputs.
     // (Also, if this is a plain fall-through, we might see another region,
     // which must not be allowed into this block's map.)
     if (pnum > PhiNode::Input         // Known multiple inputs.
         || target->is_handler()       // These have unpredictable inputs.
         || target->is_loop_head()     // Known multiple inputs
         || control()->is_Region()) {  // We must hide this guy.
       int current_bci = bci();
       set_parse_bci(target->start()); // Set target bci
       if (target->is_SEL_head()) {
         DEBUG_ONLY( target->mark_merged_backedge(block()); )
         if (target->start() == 0) {
           // Add loop predicate for the special case when
           // there are backbranches to the method entry.
           add_predicate();
         }
       }
       // Add a Region to start the new basic block.  Phis will be added
       // later lazily.
       int edges = target->pred_count();
       if (edges < pnum)  edges = pnum;  // might be a new path!
       RegionNode *r = new (C) RegionNode(edges+1);
       gvn().set_type(r, Type::CONTROL);
       record_for_igvn(r);
       // zap all inputs to NULL for debugging (done in Node(uint) constructor)
       // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
       r->init_req(pnum, control());
       set_control(r);
       set_parse_bci(current_bci); // Restore bci
     }
     // Convert the existing Parser mapping into a mapping at this bci.
     store_state_to(target);
     assert(target->is_merged(), "do not come here twice");
   } else {                      // Prior mapping at this bci
     if (TraceOptoParse) {  tty->print(" with previous state"); }
 #ifdef ASSERT
     if (target->is_SEL_head()) {
       target->mark_merged_backedge(block());
     }
 #endif
     // We must not manufacture more phis if the target is already parsed.
     bool nophi = target->is_parsed();
     SafePointNode* newin = map();// Hang on to incoming mapping
     Block* save_block = block(); // Hang on to incoming block;
     load_state_from(target);    // Get prior mapping
     assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
     assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
     assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
     assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
     // Iterate over my current mapping and the old mapping.
     // Where different, insert Phi functions.
     // Use any existing Phi functions.
     assert(control()->is_Region(), "must be merging to a region");
     RegionNode* r = control()->as_Region();
     // Compute where to merge into
     // Merge incoming control path
     r->init_req(pnum, newin->control());
     if (pnum == 1) {            // Last merge for this Region?
       if (!block()->flow()->is_irreducible_entry()) {
         Node* result = _gvn.transform_no_reclaim(r);
         if (r != result && TraceOptoParse) {
           tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
         }
       }
       record_for_igvn(r);
     }
     // Update all the non-control inputs to map:
     assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
     bool check_elide_phi = target->is_SEL_backedge(save_block);
     for (uint j = 1; j < newin->req(); j++) {
       Node* m = map()->in(j);   // Current state of target.
       Node* n = newin->in(j);   // Incoming change to target state.
       PhiNode* phi;
       if (m->is_Phi() && m->as_Phi()->region() == r)
         phi = m->as_Phi();
       else
         phi = NULL;
       if (m != n) {             // Different; must merge
         switch (j) {
         // Frame pointer and Return Address never changes
         case TypeFunc::FramePtr:// Drop m, use the original value
         case TypeFunc::ReturnAdr:
           break;
         case TypeFunc::Memory:  // Merge inputs to the MergeMem node
           assert(phi == NULL, "the merge contains phis, not vice versa");
           merge_memory_edges(n->as_MergeMem(), pnum, nophi);
           continue;
         default:                // All normal stuff
           if (phi == NULL) {
             const JVMState* jvms = map()->jvms();
             if (EliminateNestedLocks &&
                 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
               // BoxLock nodes are not commoning.
               // Use old BoxLock node as merged box.
               assert(newin->jvms()->is_monitor_box(j), "sanity");
               // This assert also tests that nodes are BoxLock.
               assert(BoxLockNode::same_slot(n, m), "sanity");
               C->gvn_replace_by(n, m);
             } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
               phi = ensure_phi(j, nophi);
             }
           }
           break;
         }
       }
       // At this point, n might be top if:
       //  - there is no phi (because TypeFlow detected a conflict), or
       //  - the corresponding control edges is top (a dead incoming path)
       // It is a bug if we create a phi which sees a garbage value on a live path.
       if (phi != NULL) {
         assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
         assert(phi->region() == r, "");
         phi->set_req(pnum, n);  // Then add 'n' to the merge
         if (pnum == PhiNode::Input) {
           // Last merge for this Phi.
           // So far, Phis have had a reasonable type from ciTypeFlow.
           // Now _gvn will join that with the meet of current inputs.
           // BOTTOM is never permissible here, 'cause pessimistically
           // Phis of pointers cannot lose the basic pointer type.
           debug_only(const Type* bt1 = phi->bottom_type());
           assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
           map()->set_req(j, _gvn.transform_no_reclaim(phi));
           debug_only(const Type* bt2 = phi->bottom_type());
           assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
           record_for_igvn(phi);
         }
       }
     } // End of for all values to be merged
     if (pnum == PhiNode::Input &&
         !r->in(0)) {         // The occasional useless Region
       assert(control() == r, "");
       set_control(r->nonnull_req());
     }
     map()->merge_replaced_nodes_with(newin);
     // newin has been subsumed into the lazy merge, and is now dead.
     set_block(save_block);
     stop();                     // done with this guy, for now
   }
   if (TraceOptoParse) {
     tty->print_cr(" on path %d", pnum);
   }
   // Done with this parser state.
   assert(stopped(), "");
 }
 //--------------------------merge_memory_edges---------------------------------
 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
   // (nophi means we must not create phis, because we already parsed here)
   assert(n != NULL, "");
   // Merge the inputs to the MergeMems
   MergeMemNode* m = merged_memory();
   assert(control()->is_Region(), "must be merging to a region");
   RegionNode* r = control()->as_Region();
   PhiNode* base = NULL;
   MergeMemNode* remerge = NULL;
   for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
     Node *p = mms.force_memory();
     Node *q = mms.memory2();
     if (mms.is_empty() && nophi) {
       // Trouble:  No new splits allowed after a loop body is parsed.
       // Instead, wire the new split into a MergeMem on the backedge.
       // The optimizer will sort it out, slicing the phi.
       if (remerge == NULL) {
         assert(base != NULL, "");
         assert(base->in(0) != NULL, "should not be xformed away");
         remerge = MergeMemNode::make(C, base->in(pnum));
         gvn().set_type(remerge, Type::MEMORY);
         base->set_req(pnum, remerge);
       }
       remerge->set_memory_at(mms.alias_idx(), q);
       continue;
     }
     assert(!q->is_MergeMem(), "");
     PhiNode* phi;
     if (p != q) {
       phi = ensure_memory_phi(mms.alias_idx(), nophi);
     } else {
       if (p->is_Phi() && p->as_Phi()->region() == r)
         phi = p->as_Phi();
       else
         phi = NULL;
     }
     // Insert q into local phi
     if (phi != NULL) {
       assert(phi->region() == r, "");
       p = phi;
       phi->set_req(pnum, q);
       if (mms.at_base_memory()) {
         base = phi;  // delay transforming it
       } else if (pnum == 1) {
         record_for_igvn(phi);
         p = _gvn.transform_no_reclaim(phi);
       }
       mms.set_memory(p);// store back through the iterator
     }
   }
   // Transform base last, in case we must fiddle with remerging.
   if (base != NULL && pnum == 1) {
     record_for_igvn(base);
     m->set_base_memory( _gvn.transform_no_reclaim(base) );
   }
 }
 //------------------------ensure_phis_everywhere-------------------------------
 void Parse::ensure_phis_everywhere() {
   ensure_phi(TypeFunc::I_O);
   // Ensure a phi on all currently known memories.
   for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
     ensure_memory_phi(mms.alias_idx());
     debug_only(mms.set_memory());  // keep the iterator happy
   }
   // Note:  This is our only chance to create phis for memory slices.
   // If we miss a slice that crops up later, it will have to be
   // merged into the base-memory phi that we are building here.
   // Later, the optimizer will comb out the knot, and build separate
   // phi-loops for each memory slice that matters.
   // Monitors must nest nicely and not get confused amongst themselves.
   // Phi-ify everything up to the monitors, though.
   uint monoff = map()->jvms()->monoff();
   uint nof_monitors = map()->jvms()->nof_monitors();
   assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
   bool check_elide_phi = block()->is_SEL_head();
   for (uint i = TypeFunc::Parms; i < monoff; i++) {
     if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
       ensure_phi(i);
     }
   }
   // Even monitors need Phis, though they are well-structured.
   // This is true for OSR methods, and also for the rare cases where
   // a monitor object is the subject of a replace_in_map operation.
   // See bugs 4426707 and 5043395.
   for (uint m = 0; m < nof_monitors; m++) {
     ensure_phi(map()->jvms()->monitor_obj_offset(m));
   }
 }
 //-----------------------------add_new_path------------------------------------
 // Add a previously unaccounted predecessor to this block.
 int Parse::Block::add_new_path() {
   // If there is no map, return the lowest unused path number.
   if (!is_merged())  return pred_count()+1;  // there will be a map shortly
   SafePointNode* map = start_map();
   if (!map->control()->is_Region())
     return pred_count()+1;  // there may be a region some day
   RegionNode* r = map->control()->as_Region();
   // Add new path to the region.
   uint pnum = r->req();
   r->add_req(NULL);
   for (uint i = 1; i < map->req(); i++) {
     Node* n = map->in(i);
     if (i == TypeFunc::Memory) {
       // Ensure a phi on all currently known memories.
       for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
         Node* phi = mms.memory();
         if (phi->is_Phi() && phi->as_Phi()->region() == r) {
           assert(phi->req() == pnum, "must be same size as region");
           phi->add_req(NULL);
         }
       }
     } else {
       if (n->is_Phi() && n->as_Phi()->region() == r) {
         assert(n->req() == pnum, "must be same size as region");
         n->add_req(NULL);
       }
     }
   }
   return pnum;
 }
 //------------------------------ensure_phi-------------------------------------
 // Turn the idx'th entry of the current map into a Phi
 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
   SafePointNode* map = this->map();
   Node* region = map->control();
   assert(region->is_Region(), "");
   Node* o = map->in(idx);
   assert(o != NULL, "");
   if (o == top())  return NULL; // TOP always merges into TOP
   if (o->is_Phi() && o->as_Phi()->region() == region) {
     return o->as_Phi();
   }
   // Now use a Phi here for merging
   assert(!nocreate, "Cannot build a phi for a block already parsed.");
   const JVMState* jvms = map->jvms();
   const Type* t = NULL;
   if (jvms->is_loc(idx)) {
     t = block()->local_type_at(idx - jvms->locoff());
   } else if (jvms->is_stk(idx)) {
     t = block()->stack_type_at(idx - jvms->stkoff());
   } else if (jvms->is_mon(idx)) {
     assert(!jvms->is_monitor_box(idx), "no phis for boxes");
     t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
   } else if ((uint)idx < TypeFunc::Parms) {
     t = o->bottom_type();  // Type::RETURN_ADDRESS or such-like.
   } else {
     assert(false, "no type information for this phi");
   }
   // If the type falls to bottom, then this must be a local that
   // is mixing ints and oops or some such.  Forcing it to top
   // makes it go dead.
   if (t == Type::BOTTOM) {
     map->set_req(idx, top());
     return NULL;
   }
   // Do not create phis for top either.
   // A top on a non-null control flow must be an unused even after the.phi.
   if (t == Type::TOP || t == Type::HALF) {
     map->set_req(idx, top());
     return NULL;
   }
   PhiNode* phi = PhiNode::make(region, o, t);
   gvn().set_type(phi, t);
   if (C->do_escape_analysis()) record_for_igvn(phi);
   map->set_req(idx, phi);
   return phi;
 }
 //--------------------------ensure_memory_phi----------------------------------
 // Turn the idx'th slice of the current memory into a Phi
 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
   MergeMemNode* mem = merged_memory();
   Node* region = control();
   assert(region->is_Region(), "");
   Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
   assert(o != NULL && o != top(), "");
   PhiNode* phi;
   if (o->is_Phi() && o->as_Phi()->region() == region) {
     phi = o->as_Phi();
     if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
       // clone the shared base memory phi to make a new memory split
       assert(!nocreate, "Cannot build a phi for a block already parsed.");
       const Type* t = phi->bottom_type();
       const TypePtr* adr_type = C->get_adr_type(idx);
       phi = phi->slice_memory(adr_type);
       gvn().set_type(phi, t);
     }
     return phi;
   }
   // Now use a Phi here for merging
   assert(!nocreate, "Cannot build a phi for a block already parsed.");
   const Type* t = o->bottom_type();
   const TypePtr* adr_type = C->get_adr_type(idx);
   phi = PhiNode::make(region, o, t, adr_type);
   gvn().set_type(phi, t);
   if (idx == Compile::AliasIdxBot)
     mem->set_base_memory(phi);
   else
     mem->set_memory_at(idx, phi);
   return phi;
 }
 //------------------------------call_register_finalizer-----------------------
 // Check the klass of the receiver and call register_finalizer if the
 // class need finalization.
 void Parse::call_register_finalizer() {
   Node* receiver = local(0);
   assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
          "must have non-null instance type");
   const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
   if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
     // The type isn't known exactly so see if CHA tells us anything.
     ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
     if (!Dependencies::has_finalizable_subclass(ik)) {
       // No finalizable subclasses so skip the dynamic check.
       C->dependencies()->assert_has_no_finalizable_subclasses(ik);
       return;
     }
   }
   // Insert a dynamic test for whether the instance needs
   // finalization.  In general this will fold up since the concrete
   // class is often visible so the access flags are constant.
   Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
   Node* klass = _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), klass_addr, TypeInstPtr::KLASS));
   Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
   Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT, MemNode::unordered);
   Node* mask  = _gvn.transform(new (C) AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
   Node* check = _gvn.transform(new (C) CmpINode(mask, intcon(0)));
   Node* test  = _gvn.transform(new (C) BoolNode(check, BoolTest::ne));
   IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
   RegionNode* result_rgn = new (C) RegionNode(3);
   record_for_igvn(result_rgn);
   Node *skip_register = _gvn.transform(new (C) IfFalseNode(iff));
   result_rgn->init_req(1, skip_register);
   Node *needs_register = _gvn.transform(new (C) IfTrueNode(iff));
   set_control(needs_register);
   if (stopped()) {
     // There is no slow path.
     result_rgn->init_req(2, top());
   } else {
     Node *call = make_runtime_call(RC_NO_LEAF,
                                    OptoRuntime::register_finalizer_Type(),
                                    OptoRuntime::register_finalizer_Java(),
                                    NULL, TypePtr::BOTTOM,
                                    receiver);
     make_slow_call_ex(call, env()->Throwable_klass(), true);
     Node* fast_io  = call->in(TypeFunc::I_O);
     Node* fast_mem = call->in(TypeFunc::Memory);
     // These two phis are pre-filled with copies of of the fast IO and Memory
     Node* io_phi   = PhiNode::make(result_rgn, fast_io,  Type::ABIO);
     Node* mem_phi  = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
     result_rgn->init_req(2, control());
     io_phi    ->init_req(2, i_o());
     mem_phi   ->init_req(2, reset_memory());
     set_all_memory( _gvn.transform(mem_phi) );
     set_i_o(        _gvn.transform(io_phi) );
   }
   set_control( _gvn.transform(result_rgn) );
 }
 // Add check to deoptimize if RTM state is not ProfileRTM
 void Parse::rtm_deopt() {
 #if INCLUDE_RTM_OPT
   if (C->profile_rtm()) {
     assert(C->method() != NULL, "only for normal compilations");
     assert(!C->method()->method_data()->is_empty(), "MDO is needed to record RTM state");
     assert(depth() == 1, "generate check only for main compiled method");
     // Set starting bci for uncommon trap.
     set_parse_bci(is_osr_parse() ? osr_bci() : 0);
     // Load the rtm_state from the MethodData.
     const TypePtr* adr_type = TypeMetadataPtr::make(C->method()->method_data());
     Node* mdo = makecon(adr_type);
     int offset = MethodData::rtm_state_offset_in_bytes();
     Node* adr_node = basic_plus_adr(mdo, mdo, offset);
     Node* rtm_state = make_load(control(), adr_node, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
     // Separate Load from Cmp by Opaque.
     // In expand_macro_nodes() it will be replaced either
     // with this load when there are locks in the code
     // or with ProfileRTM (cmp->in(2)) otherwise so that
     // the check will fold.
     Node* profile_state = makecon(TypeInt::make(ProfileRTM));
     Node* opq   = _gvn.transform( new (C) Opaque3Node(C, rtm_state, Opaque3Node::RTM_OPT) );
     Node* chk   = _gvn.transform( new (C) CmpINode(opq, profile_state) );
     Node* tst   = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
     // Branch to failure if state was changed
     { BuildCutout unless(this, tst, PROB_ALWAYS);
       uncommon_trap(Deoptimization::Reason_rtm_state_change,
                     Deoptimization::Action_make_not_entrant);
     }
   }
 #endif
 }
 //------------------------------return_current---------------------------------
 // Append current _map to _exit_return
 void Parse::return_current(Node* value) {
   if (RegisterFinalizersAtInit &&
       method()->intrinsic_id() == vmIntrinsics::_Object_init) {
     call_register_finalizer();
   }
   // Do not set_parse_bci, so that return goo is credited to the return insn.
   set_bci(InvocationEntryBci);
   if (method()->is_synchronized() && GenerateSynchronizationCode) {
     shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
   }
   if (C->env()->dtrace_method_probes()) {
     make_dtrace_method_exit(method());
   }
   SafePointNode* exit_return = _exits.map();
   exit_return->in( TypeFunc::Control  )->add_req( control() );
   exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
   Node *mem = exit_return->in( TypeFunc::Memory   );
   for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
     if (mms.is_empty()) {
       // get a copy of the base memory, and patch just this one input
       const TypePtr* adr_type = mms.adr_type(C);
       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
       gvn().set_type_bottom(phi);
       phi->del_req(phi->req()-1);  // prepare to re-patch
       mms.set_memory(phi);
     }
     mms.memory()->add_req(mms.memory2());
   }
   // frame pointer is always same, already captured
   if (value != NULL) {
     // If returning oops to an interface-return, there is a silent free
     // cast from oop to interface allowed by the Verifier.  Make it explicit
     // here.
     Node* phi = _exits.argument(0);
     const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
     if (tr && tr->klass()->is_loaded() &&
         tr->klass()->is_interface()) {
       const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
       if (tp && tp->klass()->is_loaded() &&
           !tp->klass()->is_interface()) {
         // sharpen the type eagerly; this eases certain assert checking
         if (tp->higher_equal(TypeInstPtr::NOTNULL))
           tr = tr->join_speculative(TypeInstPtr::NOTNULL)->is_instptr();
         value = _gvn.transform(new (C) CheckCastPPNode(0, value, tr));
       }
     } else {
       // Also handle returns of oop-arrays to an arrays-of-interface return
       const TypeInstPtr* phi_tip;
       const TypeInstPtr* val_tip;
       Type::get_arrays_base_elements(phi->bottom_type(), value->bottom_type(), &phi_tip, &val_tip);
       if (phi_tip != NULL && phi_tip->is_loaded() && phi_tip->klass()->is_interface() &&
           val_tip != NULL && val_tip->is_loaded() && !val_tip->klass()->is_interface()) {
          value = _gvn.transform(new (C) CheckCastPPNode(0, value, phi->bottom_type()));
       }
     }
     phi->add_req(value);
   }
   if (_first_return) {
     _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
     _first_return = false;
   } else {
     _exits.map()->merge_replaced_nodes_with(map());
   }
   stop_and_kill_map();          // This CFG path dies here
 }
 //------------------------------add_safepoint----------------------------------
 void Parse::add_safepoint() {
   // See if we can avoid this safepoint.  No need for a SafePoint immediately
   // after a Call (except Leaf Call) or another SafePoint.
   Node *proj = control();
   bool add_poll_param = SafePointNode::needs_polling_address_input();
   uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
   if( proj->is_Proj() ) {
     Node *n0 = proj->in(0);
     if( n0->is_Catch() ) {
       n0 = n0->in(0)->in(0);
       assert( n0->is_Call(), "expect a call here" );
     }
     if( n0->is_Call() ) {
       if( n0->as_Call()->guaranteed_safepoint() )
         return;
     } else if( n0->is_SafePoint() && n0->req() >= parms ) {
       return;
     }
   }
   // Clear out dead values from the debug info.
   kill_dead_locals();
   // Clone the JVM State
   SafePointNode *sfpnt = new (C) SafePointNode(parms, NULL);
   // Capture memory state BEFORE a SafePoint.  Since we can block at a
   // SafePoint we need our GC state to be safe; i.e. we need all our current
   // write barriers (card marks) to not float down after the SafePoint so we
   // must read raw memory.  Likewise we need all oop stores to match the card
   // marks.  If deopt can happen, we need ALL stores (we need the correct JVM
   // state on a deopt).
   // We do not need to WRITE the memory state after a SafePoint.  The control
   // edge will keep card-marks and oop-stores from floating up from below a
   // SafePoint and our true dependency added here will keep them from floating
   // down below a SafePoint.
   // Clone the current memory state
   Node* mem = MergeMemNode::make(C, map()->memory());
   mem = _gvn.transform(mem);
   // Pass control through the safepoint
   sfpnt->init_req(TypeFunc::Control  , control());
   // Fix edges normally used by a call
   sfpnt->init_req(TypeFunc::I_O      , top() );
   sfpnt->init_req(TypeFunc::Memory   , mem   );
   sfpnt->init_req(TypeFunc::ReturnAdr, top() );
   sfpnt->init_req(TypeFunc::FramePtr , top() );
   // Create a node for the polling address
   if( add_poll_param ) {
     Node *polladr = ConPNode::make(C, (address)os::get_polling_page());
     sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
   }
   // Fix up the JVM State edges
   add_safepoint_edges(sfpnt);
   Node *transformed_sfpnt = _gvn.transform(sfpnt);
   set_control(transformed_sfpnt);
   // Provide an edge from root to safepoint.  This makes the safepoint
   // appear useful until the parse has completed.
   if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
     assert(C->root() != NULL, "Expect parse is still valid");
     C->root()->add_prec(transformed_sfpnt);
   }
 }
 #ifndef PRODUCT
 //------------------------show_parse_info--------------------------------------
 void Parse::show_parse_info() {
   InlineTree* ilt = NULL;
   if (C->ilt() != NULL) {
     JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
     ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
   }
   if (PrintCompilation && Verbose) {
     if (depth() == 1) {
       if( ilt->count_inlines() ) {
         tty->print("    __inlined %d (%d bytes)", ilt->count_inlines(),
                      ilt->count_inline_bcs());
         tty->cr();
       }
     } else {
       if (method()->is_synchronized())         tty->print("s");
       if (method()->has_exception_handlers())  tty->print("!");
       // Check this is not the final compiled version
       if (C->trap_can_recompile()) {
         tty->print("-");
       } else {
         tty->print(" ");
       }
       method()->print_short_name();
       if (is_osr_parse()) {
         tty->print(" @ %d", osr_bci());
       }
       tty->print(" (%d bytes)",method()->code_size());
       if (ilt->count_inlines()) {
         tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
                    ilt->count_inline_bcs());
       }
       tty->cr();
     }
   }
   if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
     // Print that we succeeded; suppress this message on the first osr parse.
     if (method()->is_synchronized())         tty->print("s");
     if (method()->has_exception_handlers())  tty->print("!");
     // Check this is not the final compiled version
     if (C->trap_can_recompile() && depth() == 1) {
       tty->print("-");
     } else {
       tty->print(" ");
     }
     if( depth() != 1 ) { tty->print("   "); }  // missing compile count
     for (int i = 1; i < depth(); ++i) { tty->print("  "); }
     method()->print_short_name();
     if (is_osr_parse()) {
       tty->print(" @ %d", osr_bci());
     }
     if (ilt->caller_bci() != -1) {
       tty->print(" @ %d", ilt->caller_bci());
     }
     tty->print(" (%d bytes)",method()->code_size());
     if (ilt->count_inlines()) {
       tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
                  ilt->count_inline_bcs());
     }
     tty->cr();
   }
 }
 //------------------------------dump-------------------------------------------
 // Dump information associated with the bytecodes of current _method
 void Parse::dump() {
   if( method() != NULL ) {
     // Iterate over bytecodes
     ciBytecodeStream iter(method());
     for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
       dump_bci( iter.cur_bci() );
       tty->cr();
     }
   }
 }
 // Dump information associated with a byte code index, 'bci'
 void Parse::dump_bci(int bci) {
   // Output info on merge-points, cloning, and within _jsr..._ret
   // NYI
   tty->print(" bci:%d", bci);
 }
 #endif

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/opto/parse1.cpp@fd13a567f179 (annotated)

src/share/vm/opto/parse1.cpp