1 /*
   2  * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "asm/macroAssembler.hpp"
  27 #include "asm/macroAssembler.inline.hpp"
  28 #include "ci/ciReplay.hpp"
  29 #include "classfile/systemDictionary.hpp"
  30 #include "code/exceptionHandlerTable.hpp"
  31 #include "code/nmethod.hpp"
  32 #include "compiler/compileLog.hpp"
  33 #include "compiler/disassembler.hpp"
  34 #include "compiler/oopMap.hpp"
  35 #include "jfr/jfrEvents.hpp"
  36 #include "opto/addnode.hpp"
  37 #include "opto/block.hpp"
  38 #include "opto/c2compiler.hpp"
  39 #include "opto/callGenerator.hpp"
  40 #include "opto/callnode.hpp"
  41 #include "opto/cfgnode.hpp"
  42 #include "opto/chaitin.hpp"
  43 #include "opto/compile.hpp"
  44 #include "opto/connode.hpp"
  45 #include "opto/divnode.hpp"
  46 #include "opto/escape.hpp"
  47 #include "opto/idealGraphPrinter.hpp"
  48 #include "opto/loopnode.hpp"
  49 #include "opto/machnode.hpp"
  50 #include "opto/macro.hpp"
  51 #include "opto/matcher.hpp"
  52 #include "opto/mathexactnode.hpp"
  53 #include "opto/memnode.hpp"
  54 #include "opto/mulnode.hpp"
  55 #include "opto/node.hpp"
  56 #include "opto/opcodes.hpp"
  57 #include "opto/output.hpp"
  58 #include "opto/parse.hpp"
  59 #include "opto/phaseX.hpp"
  60 #include "opto/rootnode.hpp"
  61 #include "opto/runtime.hpp"
  62 #include "opto/stringopts.hpp"
  63 #include "opto/type.hpp"
  64 #include "opto/vectornode.hpp"
  65 #include "runtime/arguments.hpp"
  66 #include "runtime/signature.hpp"
  67 #include "runtime/stubRoutines.hpp"
  68 #include "runtime/timer.hpp"
  69 #include "utilities/copy.hpp"
  70 #if defined AD_MD_HPP
  71 # include AD_MD_HPP
  72 #elif defined TARGET_ARCH_MODEL_x86_32
  73 # include "adfiles/ad_x86_32.hpp"
  74 #elif defined TARGET_ARCH_MODEL_x86_64
  75 # include "adfiles/ad_x86_64.hpp"
  76 #elif defined TARGET_ARCH_MODEL_aarch64
  77 # include "adfiles/ad_aarch64.hpp"
  78 #elif defined TARGET_ARCH_MODEL_sparc
  79 # include "adfiles/ad_sparc.hpp"
  80 #elif defined TARGET_ARCH_MODEL_zero
  81 # include "adfiles/ad_zero.hpp"
  82 #elif defined TARGET_ARCH_MODEL_ppc_64
  83 # include "adfiles/ad_ppc_64.hpp"
  84 #endif
  85 
  86 #if INCLUDE_ALL_GCS
  87 #include "gc_implementation/shenandoah/shenandoahForwarding.hpp"
  88 #include "gc_implementation/shenandoah/c2/shenandoahSupport.hpp"
  89 #endif
  90 
  91 // -------------------- Compile::mach_constant_base_node -----------------------
  92 // Constant table base node singleton.
  93 MachConstantBaseNode* Compile::mach_constant_base_node() {
  94   if (_mach_constant_base_node == NULL) {
  95     _mach_constant_base_node = new (C) MachConstantBaseNode();
  96     _mach_constant_base_node->add_req(C->root());
  97   }
  98   return _mach_constant_base_node;
  99 }
 100 
 101 
 102 /// Support for intrinsics.
 103 
 104 // Return the index at which m must be inserted (or already exists).
 105 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
 106 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual) {
 107 #ifdef ASSERT
 108   for (int i = 1; i < _intrinsics->length(); i++) {
 109     CallGenerator* cg1 = _intrinsics->at(i-1);
 110     CallGenerator* cg2 = _intrinsics->at(i);
 111     assert(cg1->method() != cg2->method()
 112            ? cg1->method()     < cg2->method()
 113            : cg1->is_virtual() < cg2->is_virtual(),
 114            "compiler intrinsics list must stay sorted");
 115   }
 116 #endif
 117   // Binary search sorted list, in decreasing intervals [lo, hi].
 118   int lo = 0, hi = _intrinsics->length()-1;
 119   while (lo <= hi) {
 120     int mid = (uint)(hi + lo) / 2;
 121     ciMethod* mid_m = _intrinsics->at(mid)->method();
 122     if (m < mid_m) {
 123       hi = mid-1;
 124     } else if (m > mid_m) {
 125       lo = mid+1;
 126     } else {
 127       // look at minor sort key
 128       bool mid_virt = _intrinsics->at(mid)->is_virtual();
 129       if (is_virtual < mid_virt) {
 130         hi = mid-1;
 131       } else if (is_virtual > mid_virt) {
 132         lo = mid+1;
 133       } else {
 134         return mid;  // exact match
 135       }
 136     }
 137   }
 138   return lo;  // inexact match
 139 }
 140 
 141 void Compile::register_intrinsic(CallGenerator* cg) {
 142   if (_intrinsics == NULL) {
 143     _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
 144   }
 145   // This code is stolen from ciObjectFactory::insert.
 146   // Really, GrowableArray should have methods for
 147   // insert_at, remove_at, and binary_search.
 148   int len = _intrinsics->length();
 149   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual());
 150   if (index == len) {
 151     _intrinsics->append(cg);
 152   } else {
 153 #ifdef ASSERT
 154     CallGenerator* oldcg = _intrinsics->at(index);
 155     assert(oldcg->method() != cg->method() || oldcg->is_virtual() != cg->is_virtual(), "don't register twice");
 156 #endif
 157     _intrinsics->append(_intrinsics->at(len-1));
 158     int pos;
 159     for (pos = len-2; pos >= index; pos--) {
 160       _intrinsics->at_put(pos+1,_intrinsics->at(pos));
 161     }
 162     _intrinsics->at_put(index, cg);
 163   }
 164   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
 165 }
 166 
 167 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
 168   assert(m->is_loaded(), "don't try this on unloaded methods");
 169   if (_intrinsics != NULL) {
 170     int index = intrinsic_insertion_index(m, is_virtual);
 171     if (index < _intrinsics->length()
 172         && _intrinsics->at(index)->method() == m
 173         && _intrinsics->at(index)->is_virtual() == is_virtual) {
 174       return _intrinsics->at(index);
 175     }
 176   }
 177   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
 178   if (m->intrinsic_id() != vmIntrinsics::_none &&
 179       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
 180     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
 181     if (cg != NULL) {
 182       // Save it for next time:
 183       register_intrinsic(cg);
 184       return cg;
 185     } else {
 186       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
 187     }
 188   }
 189   return NULL;
 190 }
 191 
 192 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
 193 // in library_call.cpp.
 194 
 195 
 196 #ifndef PRODUCT
 197 // statistics gathering...
 198 
 199 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
 200 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
 201 
 202 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
 203   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
 204   int oflags = _intrinsic_hist_flags[id];
 205   assert(flags != 0, "what happened?");
 206   if (is_virtual) {
 207     flags |= _intrinsic_virtual;
 208   }
 209   bool changed = (flags != oflags);
 210   if ((flags & _intrinsic_worked) != 0) {
 211     juint count = (_intrinsic_hist_count[id] += 1);
 212     if (count == 1) {
 213       changed = true;           // first time
 214     }
 215     // increment the overall count also:
 216     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
 217   }
 218   if (changed) {
 219     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
 220       // Something changed about the intrinsic's virtuality.
 221       if ((flags & _intrinsic_virtual) != 0) {
 222         // This is the first use of this intrinsic as a virtual call.
 223         if (oflags != 0) {
 224           // We already saw it as a non-virtual, so note both cases.
 225           flags |= _intrinsic_both;
 226         }
 227       } else if ((oflags & _intrinsic_both) == 0) {
 228         // This is the first use of this intrinsic as a non-virtual
 229         flags |= _intrinsic_both;
 230       }
 231     }
 232     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
 233   }
 234   // update the overall flags also:
 235   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
 236   return changed;
 237 }
 238 
 239 static char* format_flags(int flags, char* buf) {
 240   buf[0] = 0;
 241   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
 242   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
 243   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
 244   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
 245   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
 246   if (buf[0] == 0)  strcat(buf, ",");
 247   assert(buf[0] == ',', "must be");
 248   return &buf[1];
 249 }
 250 
 251 void Compile::print_intrinsic_statistics() {
 252   char flagsbuf[100];
 253   ttyLocker ttyl;
 254   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
 255   tty->print_cr("Compiler intrinsic usage:");
 256   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
 257   if (total == 0)  total = 1;  // avoid div0 in case of no successes
 258   #define PRINT_STAT_LINE(name, c, f) \
 259     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
 260   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
 261     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
 262     int   flags = _intrinsic_hist_flags[id];
 263     juint count = _intrinsic_hist_count[id];
 264     if ((flags | count) != 0) {
 265       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
 266     }
 267   }
 268   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
 269   if (xtty != NULL)  xtty->tail("statistics");
 270 }
 271 
 272 void Compile::print_statistics() {
 273   { ttyLocker ttyl;
 274     if (xtty != NULL)  xtty->head("statistics type='opto'");
 275     Parse::print_statistics();
 276     PhaseCCP::print_statistics();
 277     PhaseRegAlloc::print_statistics();
 278     Scheduling::print_statistics();
 279     PhasePeephole::print_statistics();
 280     PhaseIdealLoop::print_statistics();
 281     if (xtty != NULL)  xtty->tail("statistics");
 282   }
 283   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
 284     // put this under its own <statistics> element.
 285     print_intrinsic_statistics();
 286   }
 287 }
 288 #endif //PRODUCT
 289 
 290 // Support for bundling info
 291 Bundle* Compile::node_bundling(const Node *n) {
 292   assert(valid_bundle_info(n), "oob");
 293   return &_node_bundling_base[n->_idx];
 294 }
 295 
 296 bool Compile::valid_bundle_info(const Node *n) {
 297   return (_node_bundling_limit > n->_idx);
 298 }
 299 
 300 
 301 void Compile::gvn_replace_by(Node* n, Node* nn) {
 302   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
 303     Node* use = n->last_out(i);
 304     bool is_in_table = initial_gvn()->hash_delete(use);
 305     uint uses_found = 0;
 306     for (uint j = 0; j < use->len(); j++) {
 307       if (use->in(j) == n) {
 308         if (j < use->req())
 309           use->set_req(j, nn);
 310         else
 311           use->set_prec(j, nn);
 312         uses_found++;
 313       }
 314     }
 315     if (is_in_table) {
 316       // reinsert into table
 317       initial_gvn()->hash_find_insert(use);
 318     }
 319     record_for_igvn(use);
 320     i -= uses_found;    // we deleted 1 or more copies of this edge
 321   }
 322 }
 323 
 324 
 325 static inline bool not_a_node(const Node* n) {
 326   if (n == NULL)                   return true;
 327   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
 328   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
 329   return false;
 330 }
 331 
 332 // Identify all nodes that are reachable from below, useful.
 333 // Use breadth-first pass that records state in a Unique_Node_List,
 334 // recursive traversal is slower.
 335 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
 336   int estimated_worklist_size = live_nodes();
 337   useful.map( estimated_worklist_size, NULL );  // preallocate space
 338 
 339   // Initialize worklist
 340   if (root() != NULL)     { useful.push(root()); }
 341   // If 'top' is cached, declare it useful to preserve cached node
 342   if( cached_top_node() ) { useful.push(cached_top_node()); }
 343 
 344   // Push all useful nodes onto the list, breadthfirst
 345   for( uint next = 0; next < useful.size(); ++next ) {
 346     assert( next < unique(), "Unique useful nodes < total nodes");
 347     Node *n  = useful.at(next);
 348     uint max = n->len();
 349     for( uint i = 0; i < max; ++i ) {
 350       Node *m = n->in(i);
 351       if (not_a_node(m))  continue;
 352       useful.push(m);
 353     }
 354   }
 355 }
 356 
 357 // Update dead_node_list with any missing dead nodes using useful
 358 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
 359 void Compile::update_dead_node_list(Unique_Node_List &useful) {
 360   uint max_idx = unique();
 361   VectorSet& useful_node_set = useful.member_set();
 362 
 363   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
 364     // If node with index node_idx is not in useful set,
 365     // mark it as dead in dead node list.
 366     if (! useful_node_set.test(node_idx) ) {
 367       record_dead_node(node_idx);
 368     }
 369   }
 370 }
 371 
 372 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
 373   int shift = 0;
 374   for (int i = 0; i < inlines->length(); i++) {
 375     CallGenerator* cg = inlines->at(i);
 376     CallNode* call = cg->call_node();
 377     if (shift > 0) {
 378       inlines->at_put(i-shift, cg);
 379     }
 380     if (!useful.member(call)) {
 381       shift++;
 382     }
 383   }
 384   inlines->trunc_to(inlines->length()-shift);
 385 }
 386 
 387 // Disconnect all useless nodes by disconnecting those at the boundary.
 388 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
 389   uint next = 0;
 390   while (next < useful.size()) {
 391     Node *n = useful.at(next++);
 392     if (n->is_SafePoint()) {
 393       // We're done with a parsing phase. Replaced nodes are not valid
 394       // beyond that point.
 395       n->as_SafePoint()->delete_replaced_nodes();
 396     }
 397     // Use raw traversal of out edges since this code removes out edges
 398     int max = n->outcnt();
 399     for (int j = 0; j < max; ++j) {
 400       Node* child = n->raw_out(j);
 401       if (! useful.member(child)) {
 402         assert(!child->is_top() || child != top(),
 403                "If top is cached in Compile object it is in useful list");
 404         // Only need to remove this out-edge to the useless node
 405         n->raw_del_out(j);
 406         --j;
 407         --max;
 408       }
 409     }
 410     if (n->outcnt() == 1 && n->has_special_unique_user()) {
 411       record_for_igvn(n->unique_out());
 412     }
 413     if (n->Opcode() == Op_AddP && CallLeafNode::has_only_g1_wb_pre_uses(n)) {
 414       for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
 415         record_for_igvn(n->fast_out(i));
 416       }
 417     }
 418   }
 419   // Remove useless macro and predicate opaq nodes
 420   for (int i = C->macro_count()-1; i >= 0; i--) {
 421     Node* n = C->macro_node(i);
 422     if (!useful.member(n)) {
 423       remove_macro_node(n);
 424     }
 425   }
 426   // Remove useless CastII nodes with range check dependency
 427   for (int i = range_check_cast_count() - 1; i >= 0; i--) {
 428     Node* cast = range_check_cast_node(i);
 429     if (!useful.member(cast)) {
 430       remove_range_check_cast(cast);
 431     }
 432   }
 433   // Remove useless expensive node
 434   for (int i = C->expensive_count()-1; i >= 0; i--) {
 435     Node* n = C->expensive_node(i);
 436     if (!useful.member(n)) {
 437       remove_expensive_node(n);
 438     }
 439   }
 440   for (int i = C->shenandoah_barriers_count()-1; i >= 0; i--) {
 441     ShenandoahLoadReferenceBarrierNode* n = C->shenandoah_barrier(i);
 442     if (!useful.member(n)) {
 443       remove_shenandoah_barrier(n);
 444     }
 445   }
 446   // clean up the late inline lists
 447   remove_useless_late_inlines(&_string_late_inlines, useful);
 448   remove_useless_late_inlines(&_boxing_late_inlines, useful);
 449   remove_useless_late_inlines(&_late_inlines, useful);
 450   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
 451 }
 452 
 453 //------------------------------frame_size_in_words-----------------------------
 454 // frame_slots in units of words
 455 int Compile::frame_size_in_words() const {
 456   // shift is 0 in LP32 and 1 in LP64
 457   const int shift = (LogBytesPerWord - LogBytesPerInt);
 458   int words = _frame_slots >> shift;
 459   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
 460   return words;
 461 }
 462 
 463 // To bang the stack of this compiled method we use the stack size
 464 // that the interpreter would need in case of a deoptimization. This
 465 // removes the need to bang the stack in the deoptimization blob which
 466 // in turn simplifies stack overflow handling.
 467 int Compile::bang_size_in_bytes() const {
 468   return MAX2(_interpreter_frame_size, frame_size_in_bytes());
 469 }
 470 
 471 // ============================================================================
 472 //------------------------------CompileWrapper---------------------------------
 473 class CompileWrapper : public StackObj {
 474   Compile *const _compile;
 475  public:
 476   CompileWrapper(Compile* compile);
 477 
 478   ~CompileWrapper();
 479 };
 480 
 481 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
 482   // the Compile* pointer is stored in the current ciEnv:
 483   ciEnv* env = compile->env();
 484   assert(env == ciEnv::current(), "must already be a ciEnv active");
 485   assert(env->compiler_data() == NULL, "compile already active?");
 486   env->set_compiler_data(compile);
 487   assert(compile == Compile::current(), "sanity");
 488 
 489   compile->set_type_dict(NULL);
 490   compile->set_type_hwm(NULL);
 491   compile->set_type_last_size(0);
 492   compile->set_last_tf(NULL, NULL);
 493   compile->set_indexSet_arena(NULL);
 494   compile->set_indexSet_free_block_list(NULL);
 495   compile->init_type_arena();
 496   Type::Initialize(compile);
 497   _compile->set_scratch_buffer_blob(NULL);
 498   _compile->begin_method();
 499 }
 500 CompileWrapper::~CompileWrapper() {
 501   _compile->end_method();
 502   if (_compile->scratch_buffer_blob() != NULL)
 503     BufferBlob::free(_compile->scratch_buffer_blob());
 504   _compile->env()->set_compiler_data(NULL);
 505 }
 506 
 507 
 508 //----------------------------print_compile_messages---------------------------
 509 void Compile::print_compile_messages() {
 510 #ifndef PRODUCT
 511   // Check if recompiling
 512   if (_subsume_loads == false && PrintOpto) {
 513     // Recompiling without allowing machine instructions to subsume loads
 514     tty->print_cr("*********************************************************");
 515     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
 516     tty->print_cr("*********************************************************");
 517   }
 518   if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
 519     // Recompiling without escape analysis
 520     tty->print_cr("*********************************************************");
 521     tty->print_cr("** Bailout: Recompile without escape analysis          **");
 522     tty->print_cr("*********************************************************");
 523   }
 524   if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
 525     // Recompiling without boxing elimination
 526     tty->print_cr("*********************************************************");
 527     tty->print_cr("** Bailout: Recompile without boxing elimination       **");
 528     tty->print_cr("*********************************************************");
 529   }
 530   if (env()->break_at_compile()) {
 531     // Open the debugger when compiling this method.
 532     tty->print("### Breaking when compiling: ");
 533     method()->print_short_name();
 534     tty->cr();
 535     BREAKPOINT;
 536   }
 537 
 538   if( PrintOpto ) {
 539     if (is_osr_compilation()) {
 540       tty->print("[OSR]%3d", _compile_id);
 541     } else {
 542       tty->print("%3d", _compile_id);
 543     }
 544   }
 545 #endif
 546 }
 547 
 548 
 549 //-----------------------init_scratch_buffer_blob------------------------------
 550 // Construct a temporary BufferBlob and cache it for this compile.
 551 void Compile::init_scratch_buffer_blob(int const_size) {
 552   // If there is already a scratch buffer blob allocated and the
 553   // constant section is big enough, use it.  Otherwise free the
 554   // current and allocate a new one.
 555   BufferBlob* blob = scratch_buffer_blob();
 556   if ((blob != NULL) && (const_size <= _scratch_const_size)) {
 557     // Use the current blob.
 558   } else {
 559     if (blob != NULL) {
 560       BufferBlob::free(blob);
 561     }
 562 
 563     ResourceMark rm;
 564     _scratch_const_size = const_size;
 565     int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size);
 566     blob = BufferBlob::create("Compile::scratch_buffer", size);
 567     // Record the buffer blob for next time.
 568     set_scratch_buffer_blob(blob);
 569     // Have we run out of code space?
 570     if (scratch_buffer_blob() == NULL) {
 571       // Let CompilerBroker disable further compilations.
 572       record_failure("Not enough space for scratch buffer in CodeCache");
 573       return;
 574     }
 575   }
 576 
 577   // Initialize the relocation buffers
 578   relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
 579   set_scratch_locs_memory(locs_buf);
 580 }
 581 
 582 
 583 //-----------------------scratch_emit_size-------------------------------------
 584 // Helper function that computes size by emitting code
 585 uint Compile::scratch_emit_size(const Node* n) {
 586   // Start scratch_emit_size section.
 587   set_in_scratch_emit_size(true);
 588 
 589   // Emit into a trash buffer and count bytes emitted.
 590   // This is a pretty expensive way to compute a size,
 591   // but it works well enough if seldom used.
 592   // All common fixed-size instructions are given a size
 593   // method by the AD file.
 594   // Note that the scratch buffer blob and locs memory are
 595   // allocated at the beginning of the compile task, and
 596   // may be shared by several calls to scratch_emit_size.
 597   // The allocation of the scratch buffer blob is particularly
 598   // expensive, since it has to grab the code cache lock.
 599   BufferBlob* blob = this->scratch_buffer_blob();
 600   assert(blob != NULL, "Initialize BufferBlob at start");
 601   assert(blob->size() > MAX_inst_size, "sanity");
 602   relocInfo* locs_buf = scratch_locs_memory();
 603   address blob_begin = blob->content_begin();
 604   address blob_end   = (address)locs_buf;
 605   assert(blob->content_contains(blob_end), "sanity");
 606   CodeBuffer buf(blob_begin, blob_end - blob_begin);
 607   buf.initialize_consts_size(_scratch_const_size);
 608   buf.initialize_stubs_size(MAX_stubs_size);
 609   assert(locs_buf != NULL, "sanity");
 610   int lsize = MAX_locs_size / 3;
 611   buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
 612   buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
 613   buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
 614 
 615   // Do the emission.
 616 
 617   Label fakeL; // Fake label for branch instructions.
 618   Label*   saveL = NULL;
 619   uint save_bnum = 0;
 620   bool is_branch = n->is_MachBranch();
 621   if (is_branch) {
 622     MacroAssembler masm(&buf);
 623     masm.bind(fakeL);
 624     n->as_MachBranch()->save_label(&saveL, &save_bnum);
 625     n->as_MachBranch()->label_set(&fakeL, 0);
 626   }
 627   n->emit(buf, this->regalloc());
 628 
 629   // Emitting into the scratch buffer should not fail
 630   assert (!failing(), err_msg_res("Must not have pending failure. Reason is: %s", failure_reason()));
 631 
 632   if (is_branch) // Restore label.
 633     n->as_MachBranch()->label_set(saveL, save_bnum);
 634 
 635   // End scratch_emit_size section.
 636   set_in_scratch_emit_size(false);
 637 
 638   return buf.insts_size();
 639 }
 640 
 641 
 642 // ============================================================================
 643 //------------------------------Compile standard-------------------------------
 644 debug_only( int Compile::_debug_idx = 100000; )
 645 
 646 // Compile a method.  entry_bci is -1 for normal compilations and indicates
 647 // the continuation bci for on stack replacement.
 648 
 649 
 650 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
 651                   bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing )
 652                 : Phase(Compiler),
 653                   _env(ci_env),
 654                   _log(ci_env->log()),
 655                   _compile_id(ci_env->compile_id()),
 656                   _save_argument_registers(false),
 657                   _stub_name(NULL),
 658                   _stub_function(NULL),
 659                   _stub_entry_point(NULL),
 660                   _method(target),
 661                   _entry_bci(osr_bci),
 662                   _initial_gvn(NULL),
 663                   _for_igvn(NULL),
 664                   _warm_calls(NULL),
 665                   _subsume_loads(subsume_loads),
 666                   _do_escape_analysis(do_escape_analysis),
 667                   _eliminate_boxing(eliminate_boxing),
 668                   _failure_reason(NULL),
 669                   _code_buffer("Compile::Fill_buffer"),
 670                   _orig_pc_slot(0),
 671                   _orig_pc_slot_offset_in_bytes(0),
 672                   _has_method_handle_invokes(false),
 673                   _mach_constant_base_node(NULL),
 674                   _node_bundling_limit(0),
 675                   _node_bundling_base(NULL),
 676                   _java_calls(0),
 677                   _inner_loops(0),
 678                   _scratch_const_size(-1),
 679                   _in_scratch_emit_size(false),
 680                   _dead_node_list(comp_arena()),
 681                   _dead_node_count(0),
 682 #ifndef PRODUCT
 683                   _trace_opto_output(TraceOptoOutput || method()->has_option("TraceOptoOutput")),
 684                   _in_dump_cnt(0),
 685                   _printer(IdealGraphPrinter::printer()),
 686 #endif
 687                   _congraph(NULL),
 688                   _comp_arena(mtCompiler),
 689                   _node_arena(mtCompiler),
 690                   _old_arena(mtCompiler),
 691                   _Compile_types(mtCompiler),
 692                   _replay_inline_data(NULL),
 693                   _late_inlines(comp_arena(), 2, 0, NULL),
 694                   _string_late_inlines(comp_arena(), 2, 0, NULL),
 695                   _boxing_late_inlines(comp_arena(), 2, 0, NULL),
 696                   _late_inlines_pos(0),
 697                   _number_of_mh_late_inlines(0),
 698                   _inlining_progress(false),
 699                   _inlining_incrementally(false),
 700                   _print_inlining_list(NULL),
 701                   _print_inlining_idx(0),
 702                   _interpreter_frame_size(0),
 703                   _max_node_limit(MaxNodeLimit) {
 704   C = this;
 705 
 706   CompileWrapper cw(this);
 707 #ifndef PRODUCT
 708   if (TimeCompiler2) {
 709     tty->print(" ");
 710     target->holder()->name()->print();
 711     tty->print(".");
 712     target->print_short_name();
 713     tty->print("  ");
 714   }
 715   TraceTime t1("Total compilation time", &_t_totalCompilation, TimeCompiler, TimeCompiler2);
 716   TraceTime t2(NULL, &_t_methodCompilation, TimeCompiler, false);
 717   bool print_opto_assembly = PrintOptoAssembly || _method->has_option("PrintOptoAssembly");
 718   if (!print_opto_assembly) {
 719     bool print_assembly = (PrintAssembly || _method->should_print_assembly());
 720     if (print_assembly && !Disassembler::can_decode()) {
 721       tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
 722       print_opto_assembly = true;
 723     }
 724   }
 725   set_print_assembly(print_opto_assembly);
 726   set_parsed_irreducible_loop(false);
 727 
 728   if (method()->has_option("ReplayInline")) {
 729     _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
 730   }
 731 #endif
 732   set_print_inlining(PrintInlining || method()->has_option("PrintInlining") NOT_PRODUCT( || PrintOptoInlining));
 733   set_print_intrinsics(PrintIntrinsics || method()->has_option("PrintIntrinsics"));
 734   set_has_irreducible_loop(true); // conservative until build_loop_tree() reset it
 735 
 736   if (ProfileTraps RTM_OPT_ONLY( || UseRTMLocking )) {
 737     // Make sure the method being compiled gets its own MDO,
 738     // so we can at least track the decompile_count().
 739     // Need MDO to record RTM code generation state.
 740     method()->ensure_method_data();
 741   }
 742 
 743   Init(::AliasLevel);
 744 
 745 
 746   print_compile_messages();
 747 
 748   _ilt = InlineTree::build_inline_tree_root();
 749 
 750   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
 751   assert(num_alias_types() >= AliasIdxRaw, "");
 752 
 753 #define MINIMUM_NODE_HASH  1023
 754   // Node list that Iterative GVN will start with
 755   Unique_Node_List for_igvn(comp_arena());
 756   set_for_igvn(&for_igvn);
 757 
 758   // GVN that will be run immediately on new nodes
 759   uint estimated_size = method()->code_size()*4+64;
 760   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
 761   PhaseGVN gvn(node_arena(), estimated_size);
 762   set_initial_gvn(&gvn);
 763 
 764   if (print_inlining() || print_intrinsics()) {
 765     _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
 766   }
 767   { // Scope for timing the parser
 768     TracePhase t3("parse", &_t_parser, true);
 769 
 770     // Put top into the hash table ASAP.
 771     initial_gvn()->transform_no_reclaim(top());
 772 
 773     // Set up tf(), start(), and find a CallGenerator.
 774     CallGenerator* cg = NULL;
 775     if (is_osr_compilation()) {
 776       const TypeTuple *domain = StartOSRNode::osr_domain();
 777       const TypeTuple *range = TypeTuple::make_range(method()->signature());
 778       init_tf(TypeFunc::make(domain, range));
 779       StartNode* s = new (this) StartOSRNode(root(), domain);
 780       initial_gvn()->set_type_bottom(s);
 781       init_start(s);
 782       cg = CallGenerator::for_osr(method(), entry_bci());
 783     } else {
 784       // Normal case.
 785       init_tf(TypeFunc::make(method()));
 786       StartNode* s = new (this) StartNode(root(), tf()->domain());
 787       initial_gvn()->set_type_bottom(s);
 788       init_start(s);
 789       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get && (UseG1GC || UseShenandoahGC)) {
 790         // With java.lang.ref.reference.get() we must go through the
 791         // intrinsic when G1 is enabled - even when get() is the root
 792         // method of the compile - so that, if necessary, the value in
 793         // the referent field of the reference object gets recorded by
 794         // the pre-barrier code.
 795         // Specifically, if G1 is enabled, the value in the referent
 796         // field is recorded by the G1 SATB pre barrier. This will
 797         // result in the referent being marked live and the reference
 798         // object removed from the list of discovered references during
 799         // reference processing.
 800         cg = find_intrinsic(method(), false);
 801       }
 802       if (cg == NULL) {
 803         float past_uses = method()->interpreter_invocation_count();
 804         float expected_uses = past_uses;
 805         cg = CallGenerator::for_inline(method(), expected_uses);
 806       }
 807     }
 808     if (failing())  return;
 809     if (cg == NULL) {
 810       record_method_not_compilable_all_tiers("cannot parse method");
 811       return;
 812     }
 813     JVMState* jvms = build_start_state(start(), tf());
 814     if ((jvms = cg->generate(jvms)) == NULL) {
 815       if (!failure_reason_is(C2Compiler::retry_class_loading_during_parsing())) {
 816         record_method_not_compilable("method parse failed");
 817       }
 818       return;
 819     }
 820     GraphKit kit(jvms);
 821 
 822     if (!kit.stopped()) {
 823       // Accept return values, and transfer control we know not where.
 824       // This is done by a special, unique ReturnNode bound to root.
 825       return_values(kit.jvms());
 826     }
 827 
 828     if (kit.has_exceptions()) {
 829       // Any exceptions that escape from this call must be rethrown
 830       // to whatever caller is dynamically above us on the stack.
 831       // This is done by a special, unique RethrowNode bound to root.
 832       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
 833     }
 834 
 835     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
 836 
 837     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
 838       inline_string_calls(true);
 839     }
 840 
 841     if (failing())  return;
 842 
 843     print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
 844 
 845     // Remove clutter produced by parsing.
 846     if (!failing()) {
 847       ResourceMark rm;
 848       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
 849     }
 850   }
 851 
 852   // Note:  Large methods are capped off in do_one_bytecode().
 853   if (failing())  return;
 854 
 855   // After parsing, node notes are no longer automagic.
 856   // They must be propagated by register_new_node_with_optimizer(),
 857   // clone(), or the like.
 858   set_default_node_notes(NULL);
 859 
 860   for (;;) {
 861     int successes = Inline_Warm();
 862     if (failing())  return;
 863     if (successes == 0)  break;
 864   }
 865 
 866   // Drain the list.
 867   Finish_Warm();
 868 #ifndef PRODUCT
 869   if (_printer) {
 870     _printer->print_inlining(this);
 871   }
 872 #endif
 873 
 874   if (failing())  return;
 875   NOT_PRODUCT( verify_graph_edges(); )
 876 
 877   // Now optimize
 878   Optimize();
 879   if (failing())  return;
 880   NOT_PRODUCT( verify_graph_edges(); )
 881 
 882 #ifndef PRODUCT
 883   if (PrintIdeal) {
 884     ttyLocker ttyl;  // keep the following output all in one block
 885     // This output goes directly to the tty, not the compiler log.
 886     // To enable tools to match it up with the compilation activity,
 887     // be sure to tag this tty output with the compile ID.
 888     if (xtty != NULL) {
 889       xtty->head("ideal compile_id='%d'%s", compile_id(),
 890                  is_osr_compilation()    ? " compile_kind='osr'" :
 891                  "");
 892     }
 893     root()->dump(9999);
 894     if (xtty != NULL) {
 895       xtty->tail("ideal");
 896     }
 897   }
 898 #endif
 899 
 900   NOT_PRODUCT( verify_barriers(); )
 901 
 902   // Dump compilation data to replay it.
 903   if (method()->has_option("DumpReplay")) {
 904     env()->dump_replay_data(_compile_id);
 905   }
 906   if (method()->has_option("DumpInline") && (ilt() != NULL)) {
 907     env()->dump_inline_data(_compile_id);
 908   }
 909 
 910   // Now that we know the size of all the monitors we can add a fixed slot
 911   // for the original deopt pc.
 912 
 913   _orig_pc_slot =  fixed_slots();
 914   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
 915   set_fixed_slots(next_slot);
 916 
 917   // Compute when to use implicit null checks. Used by matching trap based
 918   // nodes and NullCheck optimization.
 919   set_allowed_deopt_reasons();
 920 
 921   // Now generate code
 922   Code_Gen();
 923   if (failing())  return;
 924 
 925   // Check if we want to skip execution of all compiled code.
 926   {
 927 #ifndef PRODUCT
 928     if (OptoNoExecute) {
 929       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
 930       return;
 931     }
 932     TracePhase t2("install_code", &_t_registerMethod, TimeCompiler);
 933 #endif
 934 
 935     if (is_osr_compilation()) {
 936       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
 937       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
 938     } else {
 939       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
 940       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
 941     }
 942 
 943     env()->register_method(_method, _entry_bci,
 944                            &_code_offsets,
 945                            _orig_pc_slot_offset_in_bytes,
 946                            code_buffer(),
 947                            frame_size_in_words(), _oop_map_set,
 948                            &_handler_table, &_inc_table,
 949                            compiler,
 950                            env()->comp_level(),
 951                            has_unsafe_access(),
 952                            SharedRuntime::is_wide_vector(max_vector_size()),
 953                            rtm_state()
 954                            );
 955 
 956     if (log() != NULL) // Print code cache state into compiler log
 957       log()->code_cache_state();
 958   }
 959 }
 960 
 961 //------------------------------Compile----------------------------------------
 962 // Compile a runtime stub
 963 Compile::Compile( ciEnv* ci_env,
 964                   TypeFunc_generator generator,
 965                   address stub_function,
 966                   const char *stub_name,
 967                   int is_fancy_jump,
 968                   bool pass_tls,
 969                   bool save_arg_registers,
 970                   bool return_pc )
 971   : Phase(Compiler),
 972     _env(ci_env),
 973     _log(ci_env->log()),
 974     _compile_id(0),
 975     _save_argument_registers(save_arg_registers),
 976     _method(NULL),
 977     _stub_name(stub_name),
 978     _stub_function(stub_function),
 979     _stub_entry_point(NULL),
 980     _entry_bci(InvocationEntryBci),
 981     _initial_gvn(NULL),
 982     _for_igvn(NULL),
 983     _warm_calls(NULL),
 984     _orig_pc_slot(0),
 985     _orig_pc_slot_offset_in_bytes(0),
 986     _subsume_loads(true),
 987     _do_escape_analysis(false),
 988     _eliminate_boxing(false),
 989     _failure_reason(NULL),
 990     _code_buffer("Compile::Fill_buffer"),
 991     _has_method_handle_invokes(false),
 992     _mach_constant_base_node(NULL),
 993     _node_bundling_limit(0),
 994     _node_bundling_base(NULL),
 995     _java_calls(0),
 996     _inner_loops(0),
 997 #ifndef PRODUCT
 998     _trace_opto_output(TraceOptoOutput),
 999     _in_dump_cnt(0),
1000     _printer(NULL),
1001 #endif
1002     _comp_arena(mtCompiler),
1003     _node_arena(mtCompiler),
1004     _old_arena(mtCompiler),
1005     _Compile_types(mtCompiler),
1006     _dead_node_list(comp_arena()),
1007     _dead_node_count(0),
1008     _congraph(NULL),
1009     _replay_inline_data(NULL),
1010     _number_of_mh_late_inlines(0),
1011     _inlining_progress(false),
1012     _inlining_incrementally(false),
1013     _print_inlining_list(NULL),
1014     _print_inlining_idx(0),
1015     _allowed_reasons(0),
1016     _interpreter_frame_size(0),
1017     _max_node_limit(MaxNodeLimit) {
1018   C = this;
1019 
1020 #ifndef PRODUCT
1021   TraceTime t1(NULL, &_t_totalCompilation, TimeCompiler, false);
1022   TraceTime t2(NULL, &_t_stubCompilation, TimeCompiler, false);
1023   set_print_assembly(PrintFrameConverterAssembly);
1024   set_parsed_irreducible_loop(false);
1025 #endif
1026   set_has_irreducible_loop(false); // no loops
1027 
1028   CompileWrapper cw(this);
1029   Init(/*AliasLevel=*/ 0);
1030   init_tf((*generator)());
1031 
1032   {
1033     // The following is a dummy for the sake of GraphKit::gen_stub
1034     Unique_Node_List for_igvn(comp_arena());
1035     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
1036     PhaseGVN gvn(Thread::current()->resource_area(),255);
1037     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
1038     gvn.transform_no_reclaim(top());
1039 
1040     GraphKit kit;
1041     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
1042   }
1043 
1044   NOT_PRODUCT( verify_graph_edges(); )
1045   Code_Gen();
1046   if (failing())  return;
1047 
1048 
1049   // Entry point will be accessed using compile->stub_entry_point();
1050   if (code_buffer() == NULL) {
1051     Matcher::soft_match_failure();
1052   } else {
1053     if (PrintAssembly && (WizardMode || Verbose))
1054       tty->print_cr("### Stub::%s", stub_name);
1055 
1056     if (!failing()) {
1057       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
1058 
1059       // Make the NMethod
1060       // For now we mark the frame as never safe for profile stackwalking
1061       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
1062                                                       code_buffer(),
1063                                                       CodeOffsets::frame_never_safe,
1064                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
1065                                                       frame_size_in_words(),
1066                                                       _oop_map_set,
1067                                                       save_arg_registers);
1068       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
1069 
1070       _stub_entry_point = rs->entry_point();
1071     }
1072   }
1073 }
1074 
1075 //------------------------------Init-------------------------------------------
1076 // Prepare for a single compilation
1077 void Compile::Init(int aliaslevel) {
1078   _unique  = 0;
1079   _regalloc = NULL;
1080 
1081   _tf      = NULL;  // filled in later
1082   _top     = NULL;  // cached later
1083   _matcher = NULL;  // filled in later
1084   _cfg     = NULL;  // filled in later
1085 
1086   set_24_bit_selection_and_mode(Use24BitFP, false);
1087 
1088   _node_note_array = NULL;
1089   _default_node_notes = NULL;
1090 
1091   _immutable_memory = NULL; // filled in at first inquiry
1092 
1093   // Globally visible Nodes
1094   // First set TOP to NULL to give safe behavior during creation of RootNode
1095   set_cached_top_node(NULL);
1096   set_root(new (this) RootNode());
1097   // Now that you have a Root to point to, create the real TOP
1098   set_cached_top_node( new (this) ConNode(Type::TOP) );
1099   set_recent_alloc(NULL, NULL);
1100 
1101   // Create Debug Information Recorder to record scopes, oopmaps, etc.
1102   env()->set_oop_recorder(new OopRecorder(env()->arena()));
1103   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
1104   env()->set_dependencies(new Dependencies(env()));
1105 
1106   _fixed_slots = 0;
1107   set_has_split_ifs(false);
1108   set_has_loops(has_method() && method()->has_loops()); // first approximation
1109   set_has_stringbuilder(false);
1110   set_has_boxed_value(false);
1111   _trap_can_recompile = false;  // no traps emitted yet
1112   _major_progress = true; // start out assuming good things will happen
1113   set_has_unsafe_access(false);
1114   set_max_vector_size(0);
1115   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
1116   set_decompile_count(0);
1117 
1118   set_do_freq_based_layout(BlockLayoutByFrequency || method_has_option("BlockLayoutByFrequency"));
1119   set_num_loop_opts(LoopOptsCount);
1120   set_do_inlining(Inline);
1121   set_max_inline_size(MaxInlineSize);
1122   set_freq_inline_size(FreqInlineSize);
1123   set_do_scheduling(OptoScheduling);
1124   set_do_count_invocations(false);
1125   set_do_method_data_update(false);
1126   set_rtm_state(NoRTM); // No RTM lock eliding by default
1127   method_has_option_value("MaxNodeLimit", _max_node_limit);
1128 #if INCLUDE_RTM_OPT
1129   if (UseRTMLocking && has_method() && (method()->method_data_or_null() != NULL)) {
1130     int rtm_state = method()->method_data()->rtm_state();
1131     if (method_has_option("NoRTMLockEliding") || ((rtm_state & NoRTM) != 0)) {
1132       // Don't generate RTM lock eliding code.
1133       set_rtm_state(NoRTM);
1134     } else if (method_has_option("UseRTMLockEliding") || ((rtm_state & UseRTM) != 0) || !UseRTMDeopt) {
1135       // Generate RTM lock eliding code without abort ratio calculation code.
1136       set_rtm_state(UseRTM);
1137     } else if (UseRTMDeopt) {
1138       // Generate RTM lock eliding code and include abort ratio calculation
1139       // code if UseRTMDeopt is on.
1140       set_rtm_state(ProfileRTM);
1141     }
1142   }
1143 #endif
1144   if (debug_info()->recording_non_safepoints()) {
1145     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
1146                         (comp_arena(), 8, 0, NULL));
1147     set_default_node_notes(Node_Notes::make(this));
1148   }
1149 
1150   // // -- Initialize types before each compile --
1151   // // Update cached type information
1152   // if( _method && _method->constants() )
1153   //   Type::update_loaded_types(_method, _method->constants());
1154 
1155   // Init alias_type map.
1156   if (!_do_escape_analysis && aliaslevel == 3)
1157     aliaslevel = 2;  // No unique types without escape analysis
1158   _AliasLevel = aliaslevel;
1159   const int grow_ats = 16;
1160   _max_alias_types = grow_ats;
1161   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1162   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
1163   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1164   {
1165     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
1166   }
1167   // Initialize the first few types.
1168   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
1169   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1170   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1171   _num_alias_types = AliasIdxRaw+1;
1172   // Zero out the alias type cache.
1173   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1174   // A NULL adr_type hits in the cache right away.  Preload the right answer.
1175   probe_alias_cache(NULL)->_index = AliasIdxTop;
1176 
1177   _intrinsics = NULL;
1178   _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1179   _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1180   _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1181   _range_check_casts = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1182   _shenandoah_barriers = new(comp_arena()) GrowableArray<ShenandoahLoadReferenceBarrierNode*>(comp_arena(), 8,  0, NULL);
1183   register_library_intrinsics();
1184 #ifdef ASSERT
1185   _type_verify_symmetry = true;
1186 #endif
1187 }
1188 
1189 //---------------------------init_start----------------------------------------
1190 // Install the StartNode on this compile object.
1191 void Compile::init_start(StartNode* s) {
1192   if (failing())
1193     return; // already failing
1194   assert(s == start(), "");
1195 }
1196 
1197 StartNode* Compile::start() const {
1198   assert(!failing(), "");
1199   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1200     Node* start = root()->fast_out(i);
1201     if( start->is_Start() )
1202       return start->as_Start();
1203   }
1204   fatal("Did not find Start node!");
1205   return NULL;
1206 }
1207 
1208 //-------------------------------immutable_memory-------------------------------------
1209 // Access immutable memory
1210 Node* Compile::immutable_memory() {
1211   if (_immutable_memory != NULL) {
1212     return _immutable_memory;
1213   }
1214   StartNode* s = start();
1215   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1216     Node *p = s->fast_out(i);
1217     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1218       _immutable_memory = p;
1219       return _immutable_memory;
1220     }
1221   }
1222   ShouldNotReachHere();
1223   return NULL;
1224 }
1225 
1226 //----------------------set_cached_top_node------------------------------------
1227 // Install the cached top node, and make sure Node::is_top works correctly.
1228 void Compile::set_cached_top_node(Node* tn) {
1229   if (tn != NULL)  verify_top(tn);
1230   Node* old_top = _top;
1231   _top = tn;
1232   // Calling Node::setup_is_top allows the nodes the chance to adjust
1233   // their _out arrays.
1234   if (_top != NULL)     _top->setup_is_top();
1235   if (old_top != NULL)  old_top->setup_is_top();
1236   assert(_top == NULL || top()->is_top(), "");
1237 }
1238 
1239 #ifdef ASSERT
1240 uint Compile::count_live_nodes_by_graph_walk() {
1241   Unique_Node_List useful(comp_arena());
1242   // Get useful node list by walking the graph.
1243   identify_useful_nodes(useful);
1244   return useful.size();
1245 }
1246 
1247 void Compile::print_missing_nodes() {
1248 
1249   // Return if CompileLog is NULL and PrintIdealNodeCount is false.
1250   if ((_log == NULL) && (! PrintIdealNodeCount)) {
1251     return;
1252   }
1253 
1254   // This is an expensive function. It is executed only when the user
1255   // specifies VerifyIdealNodeCount option or otherwise knows the
1256   // additional work that needs to be done to identify reachable nodes
1257   // by walking the flow graph and find the missing ones using
1258   // _dead_node_list.
1259 
1260   Unique_Node_List useful(comp_arena());
1261   // Get useful node list by walking the graph.
1262   identify_useful_nodes(useful);
1263 
1264   uint l_nodes = C->live_nodes();
1265   uint l_nodes_by_walk = useful.size();
1266 
1267   if (l_nodes != l_nodes_by_walk) {
1268     if (_log != NULL) {
1269       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
1270       _log->stamp();
1271       _log->end_head();
1272     }
1273     VectorSet& useful_member_set = useful.member_set();
1274     int last_idx = l_nodes_by_walk;
1275     for (int i = 0; i < last_idx; i++) {
1276       if (useful_member_set.test(i)) {
1277         if (_dead_node_list.test(i)) {
1278           if (_log != NULL) {
1279             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
1280           }
1281           if (PrintIdealNodeCount) {
1282             // Print the log message to tty
1283               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
1284               useful.at(i)->dump();
1285           }
1286         }
1287       }
1288       else if (! _dead_node_list.test(i)) {
1289         if (_log != NULL) {
1290           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
1291         }
1292         if (PrintIdealNodeCount) {
1293           // Print the log message to tty
1294           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
1295         }
1296       }
1297     }
1298     if (_log != NULL) {
1299       _log->tail("mismatched_nodes");
1300     }
1301   }
1302 }
1303 #endif
1304 
1305 #ifndef PRODUCT
1306 void Compile::verify_top(Node* tn) const {
1307   if (tn != NULL) {
1308     assert(tn->is_Con(), "top node must be a constant");
1309     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1310     assert(tn->in(0) != NULL, "must have live top node");
1311   }
1312 }
1313 #endif
1314 
1315 
1316 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1317 
1318 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1319   guarantee(arr != NULL, "");
1320   int num_blocks = arr->length();
1321   if (grow_by < num_blocks)  grow_by = num_blocks;
1322   int num_notes = grow_by * _node_notes_block_size;
1323   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1324   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1325   while (num_notes > 0) {
1326     arr->append(notes);
1327     notes     += _node_notes_block_size;
1328     num_notes -= _node_notes_block_size;
1329   }
1330   assert(num_notes == 0, "exact multiple, please");
1331 }
1332 
1333 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1334   if (source == NULL || dest == NULL)  return false;
1335 
1336   if (dest->is_Con())
1337     return false;               // Do not push debug info onto constants.
1338 
1339 #ifdef ASSERT
1340   // Leave a bread crumb trail pointing to the original node:
1341   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1342     dest->set_debug_orig(source);
1343   }
1344 #endif
1345 
1346   if (node_note_array() == NULL)
1347     return false;               // Not collecting any notes now.
1348 
1349   // This is a copy onto a pre-existing node, which may already have notes.
1350   // If both nodes have notes, do not overwrite any pre-existing notes.
1351   Node_Notes* source_notes = node_notes_at(source->_idx);
1352   if (source_notes == NULL || source_notes->is_clear())  return false;
1353   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
1354   if (dest_notes == NULL || dest_notes->is_clear()) {
1355     return set_node_notes_at(dest->_idx, source_notes);
1356   }
1357 
1358   Node_Notes merged_notes = (*source_notes);
1359   // The order of operations here ensures that dest notes will win...
1360   merged_notes.update_from(dest_notes);
1361   return set_node_notes_at(dest->_idx, &merged_notes);
1362 }
1363 
1364 
1365 //--------------------------allow_range_check_smearing-------------------------
1366 // Gating condition for coalescing similar range checks.
1367 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1368 // single covering check that is at least as strong as any of them.
1369 // If the optimization succeeds, the simplified (strengthened) range check
1370 // will always succeed.  If it fails, we will deopt, and then give up
1371 // on the optimization.
1372 bool Compile::allow_range_check_smearing() const {
1373   // If this method has already thrown a range-check,
1374   // assume it was because we already tried range smearing
1375   // and it failed.
1376   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1377   return !already_trapped;
1378 }
1379 
1380 
1381 //------------------------------flatten_alias_type-----------------------------
1382 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1383   int offset = tj->offset();
1384   TypePtr::PTR ptr = tj->ptr();
1385 
1386   // Known instance (scalarizable allocation) alias only with itself.
1387   bool is_known_inst = tj->isa_oopptr() != NULL &&
1388                        tj->is_oopptr()->is_known_instance();
1389 
1390   // Process weird unsafe references.
1391   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1392     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
1393     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1394     tj = TypeOopPtr::BOTTOM;
1395     ptr = tj->ptr();
1396     offset = tj->offset();
1397   }
1398 
1399   // Array pointers need some flattening
1400   const TypeAryPtr *ta = tj->isa_aryptr();
1401   if (ta && ta->is_stable()) {
1402     // Erase stability property for alias analysis.
1403     tj = ta = ta->cast_to_stable(false);
1404   }
1405   if( ta && is_known_inst ) {
1406     if ( offset != Type::OffsetBot &&
1407          offset > arrayOopDesc::length_offset_in_bytes() ) {
1408       offset = Type::OffsetBot; // Flatten constant access into array body only
1409       tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
1410     }
1411   } else if( ta && _AliasLevel >= 2 ) {
1412     // For arrays indexed by constant indices, we flatten the alias
1413     // space to include all of the array body.  Only the header, klass
1414     // and array length can be accessed un-aliased.
1415     if( offset != Type::OffsetBot ) {
1416       if( ta->const_oop() ) { // MethodData* or Method*
1417         offset = Type::OffsetBot;   // Flatten constant access into array body
1418         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
1419       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1420         // range is OK as-is.
1421         tj = ta = TypeAryPtr::RANGE;
1422       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1423         tj = TypeInstPtr::KLASS; // all klass loads look alike
1424         ta = TypeAryPtr::RANGE; // generic ignored junk
1425         ptr = TypePtr::BotPTR;
1426       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1427         tj = TypeInstPtr::MARK;
1428         ta = TypeAryPtr::RANGE; // generic ignored junk
1429         ptr = TypePtr::BotPTR;
1430       } else {                  // Random constant offset into array body
1431         offset = Type::OffsetBot;   // Flatten constant access into array body
1432         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
1433       }
1434     }
1435     // Arrays of fixed size alias with arrays of unknown size.
1436     if (ta->size() != TypeInt::POS) {
1437       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1438       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
1439     }
1440     // Arrays of known objects become arrays of unknown objects.
1441     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1442       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1443       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1444     }
1445     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1446       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1447       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1448     }
1449     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1450     // cannot be distinguished by bytecode alone.
1451     if (ta->elem() == TypeInt::BOOL) {
1452       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1453       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1454       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
1455     }
1456     // During the 2nd round of IterGVN, NotNull castings are removed.
1457     // Make sure the Bottom and NotNull variants alias the same.
1458     // Also, make sure exact and non-exact variants alias the same.
1459     if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != NULL) {
1460       tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
1461     }
1462   }
1463 
1464   // Oop pointers need some flattening
1465   const TypeInstPtr *to = tj->isa_instptr();
1466   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1467     ciInstanceKlass *k = to->klass()->as_instance_klass();
1468     if( ptr == TypePtr::Constant ) {
1469       if (to->klass() != ciEnv::current()->Class_klass() ||
1470           offset < k->size_helper() * wordSize) {
1471         // No constant oop pointers (such as Strings); they alias with
1472         // unknown strings.
1473         assert(!is_known_inst, "not scalarizable allocation");
1474         tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1475       }
1476     } else if( is_known_inst ) {
1477       tj = to; // Keep NotNull and klass_is_exact for instance type
1478     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1479       // During the 2nd round of IterGVN, NotNull castings are removed.
1480       // Make sure the Bottom and NotNull variants alias the same.
1481       // Also, make sure exact and non-exact variants alias the same.
1482       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1483     }
1484     if (to->speculative() != NULL) {
1485       tj = to = TypeInstPtr::make(to->ptr(),to->klass(),to->klass_is_exact(),to->const_oop(),to->offset(), to->instance_id());
1486     }
1487     // Canonicalize the holder of this field
1488     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1489       // First handle header references such as a LoadKlassNode, even if the
1490       // object's klass is unloaded at compile time (4965979).
1491       if (!is_known_inst) { // Do it only for non-instance types
1492         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
1493       }
1494     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1495       // Static fields are in the space above the normal instance
1496       // fields in the java.lang.Class instance.
1497       if (to->klass() != ciEnv::current()->Class_klass()) {
1498         to = NULL;
1499         tj = TypeOopPtr::BOTTOM;
1500         offset = tj->offset();
1501       }
1502     } else {
1503       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1504       if (!k->equals(canonical_holder) || tj->offset() != offset) {
1505         if( is_known_inst ) {
1506           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
1507         } else {
1508           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
1509         }
1510       }
1511     }
1512   }
1513 
1514   // Klass pointers to object array klasses need some flattening
1515   const TypeKlassPtr *tk = tj->isa_klassptr();
1516   if( tk ) {
1517     // If we are referencing a field within a Klass, we need
1518     // to assume the worst case of an Object.  Both exact and
1519     // inexact types must flatten to the same alias class so
1520     // use NotNull as the PTR.
1521     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1522 
1523       tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
1524                                    TypeKlassPtr::OBJECT->klass(),
1525                                    offset);
1526     }
1527 
1528     ciKlass* klass = tk->klass();
1529     if( klass->is_obj_array_klass() ) {
1530       ciKlass* k = TypeAryPtr::OOPS->klass();
1531       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
1532         k = TypeInstPtr::BOTTOM->klass();
1533       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
1534     }
1535 
1536     // Check for precise loads from the primary supertype array and force them
1537     // to the supertype cache alias index.  Check for generic array loads from
1538     // the primary supertype array and also force them to the supertype cache
1539     // alias index.  Since the same load can reach both, we need to merge
1540     // these 2 disparate memories into the same alias class.  Since the
1541     // primary supertype array is read-only, there's no chance of confusion
1542     // where we bypass an array load and an array store.
1543     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1544     if (offset == Type::OffsetBot ||
1545         (offset >= primary_supers_offset &&
1546          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1547         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1548       offset = in_bytes(Klass::secondary_super_cache_offset());
1549       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
1550     }
1551   }
1552 
1553   // Flatten all Raw pointers together.
1554   if (tj->base() == Type::RawPtr)
1555     tj = TypeRawPtr::BOTTOM;
1556 
1557   if (tj->base() == Type::AnyPtr)
1558     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
1559 
1560   // Flatten all to bottom for now
1561   switch( _AliasLevel ) {
1562   case 0:
1563     tj = TypePtr::BOTTOM;
1564     break;
1565   case 1:                       // Flatten to: oop, static, field or array
1566     switch (tj->base()) {
1567     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
1568     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
1569     case Type::AryPtr:   // do not distinguish arrays at all
1570     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
1571     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1572     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
1573     default: ShouldNotReachHere();
1574     }
1575     break;
1576   case 2:                       // No collapsing at level 2; keep all splits
1577   case 3:                       // No collapsing at level 3; keep all splits
1578     break;
1579   default:
1580     Unimplemented();
1581   }
1582 
1583   offset = tj->offset();
1584   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1585 
1586   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1587           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1588           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1589           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1590           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1591           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1592           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr)  ,
1593           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1594   assert( tj->ptr() != TypePtr::TopPTR &&
1595           tj->ptr() != TypePtr::AnyNull &&
1596           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1597 //    assert( tj->ptr() != TypePtr::Constant ||
1598 //            tj->base() == Type::RawPtr ||
1599 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
1600 
1601   return tj;
1602 }
1603 
1604 void Compile::AliasType::Init(int i, const TypePtr* at) {
1605   _index = i;
1606   _adr_type = at;
1607   _field = NULL;
1608   _element = NULL;
1609   _is_rewritable = true; // default
1610   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1611   if (atoop != NULL && atoop->is_known_instance()) {
1612     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1613     _general_index = Compile::current()->get_alias_index(gt);
1614   } else {
1615     _general_index = 0;
1616   }
1617 }
1618 
1619 BasicType Compile::AliasType::basic_type() const {
1620   if (element() != NULL) {
1621     const Type* element = adr_type()->is_aryptr()->elem();
1622     return element->isa_narrowoop() ? T_OBJECT : element->array_element_basic_type();
1623   } if (field() != NULL) {
1624     return field()->layout_type();
1625   } else {
1626     return T_ILLEGAL; // unknown
1627   }
1628 }
1629 
1630 //---------------------------------print_on------------------------------------
1631 #ifndef PRODUCT
1632 void Compile::AliasType::print_on(outputStream* st) {
1633   if (index() < 10)
1634         st->print("@ <%d> ", index());
1635   else  st->print("@ <%d>",  index());
1636   st->print(is_rewritable() ? "   " : " RO");
1637   int offset = adr_type()->offset();
1638   if (offset == Type::OffsetBot)
1639         st->print(" +any");
1640   else  st->print(" +%-3d", offset);
1641   st->print(" in ");
1642   adr_type()->dump_on(st);
1643   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1644   if (field() != NULL && tjp) {
1645     if (tjp->klass()  != field()->holder() ||
1646         tjp->offset() != field()->offset_in_bytes()) {
1647       st->print(" != ");
1648       field()->print();
1649       st->print(" ***");
1650     }
1651   }
1652 }
1653 
1654 void print_alias_types() {
1655   Compile* C = Compile::current();
1656   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1657   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1658     C->alias_type(idx)->print_on(tty);
1659     tty->cr();
1660   }
1661 }
1662 #endif
1663 
1664 
1665 //----------------------------probe_alias_cache--------------------------------
1666 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1667   intptr_t key = (intptr_t) adr_type;
1668   key ^= key >> logAliasCacheSize;
1669   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1670 }
1671 
1672 
1673 //-----------------------------grow_alias_types--------------------------------
1674 void Compile::grow_alias_types() {
1675   const int old_ats  = _max_alias_types; // how many before?
1676   const int new_ats  = old_ats;          // how many more?
1677   const int grow_ats = old_ats+new_ats;  // how many now?
1678   _max_alias_types = grow_ats;
1679   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1680   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1681   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1682   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
1683 }
1684 
1685 
1686 //--------------------------------find_alias_type------------------------------
1687 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1688   if (_AliasLevel == 0)
1689     return alias_type(AliasIdxBot);
1690 
1691   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1692   if (ace->_adr_type == adr_type) {
1693     return alias_type(ace->_index);
1694   }
1695 
1696   // Handle special cases.
1697   if (adr_type == NULL)             return alias_type(AliasIdxTop);
1698   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
1699 
1700   // Do it the slow way.
1701   const TypePtr* flat = flatten_alias_type(adr_type);
1702 
1703 #ifdef ASSERT
1704   {
1705     ResourceMark rm;
1706     assert(flat == flatten_alias_type(flat),
1707            err_msg("not idempotent: adr_type = %s; flat = %s => %s", Type::str(adr_type),
1708                    Type::str(flat), Type::str(flatten_alias_type(flat))));
1709     assert(flat != TypePtr::BOTTOM,
1710            err_msg("cannot alias-analyze an untyped ptr: adr_type = %s", Type::str(adr_type)));
1711     if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1712       const TypeOopPtr* foop = flat->is_oopptr();
1713       // Scalarizable allocations have exact klass always.
1714       bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1715       const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1716       assert(foop == flatten_alias_type(xoop),
1717              err_msg("exactness must not affect alias type: foop = %s; xoop = %s",
1718                      Type::str(foop), Type::str(xoop)));
1719     }
1720   }
1721 #endif
1722 
1723   int idx = AliasIdxTop;
1724   for (int i = 0; i < num_alias_types(); i++) {
1725     if (alias_type(i)->adr_type() == flat) {
1726       idx = i;
1727       break;
1728     }
1729   }
1730 
1731   if (idx == AliasIdxTop) {
1732     if (no_create)  return NULL;
1733     // Grow the array if necessary.
1734     if (_num_alias_types == _max_alias_types)  grow_alias_types();
1735     // Add a new alias type.
1736     idx = _num_alias_types++;
1737     _alias_types[idx]->Init(idx, flat);
1738     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
1739     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
1740     if (flat->isa_instptr()) {
1741       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1742           && flat->is_instptr()->klass() == env()->Class_klass())
1743         alias_type(idx)->set_rewritable(false);
1744     }
1745     if (flat->isa_aryptr()) {
1746 #ifdef ASSERT
1747       const int header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1748       // (T_BYTE has the weakest alignment and size restrictions...)
1749       assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
1750 #endif
1751       if (flat->offset() == TypePtr::OffsetBot) {
1752         alias_type(idx)->set_element(flat->is_aryptr()->elem());
1753       }
1754     }
1755     if (flat->isa_klassptr()) {
1756       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1757         alias_type(idx)->set_rewritable(false);
1758       if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
1759         alias_type(idx)->set_rewritable(false);
1760       if (flat->offset() == in_bytes(Klass::access_flags_offset()))
1761         alias_type(idx)->set_rewritable(false);
1762       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1763         alias_type(idx)->set_rewritable(false);
1764     }
1765     // %%% (We would like to finalize JavaThread::threadObj_offset(),
1766     // but the base pointer type is not distinctive enough to identify
1767     // references into JavaThread.)
1768 
1769     // Check for final fields.
1770     const TypeInstPtr* tinst = flat->isa_instptr();
1771     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1772       ciField* field;
1773       if (tinst->const_oop() != NULL &&
1774           tinst->klass() == ciEnv::current()->Class_klass() &&
1775           tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
1776         // static field
1777         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1778         field = k->get_field_by_offset(tinst->offset(), true);
1779       } else {
1780         ciInstanceKlass *k = tinst->klass()->as_instance_klass();
1781         field = k->get_field_by_offset(tinst->offset(), false);
1782       }
1783       assert(field == NULL ||
1784              original_field == NULL ||
1785              (field->holder() == original_field->holder() &&
1786               field->offset() == original_field->offset() &&
1787               field->is_static() == original_field->is_static()), "wrong field?");
1788       // Set field() and is_rewritable() attributes.
1789       if (field != NULL)  alias_type(idx)->set_field(field);
1790     }
1791   }
1792 
1793   // Fill the cache for next time.
1794   ace->_adr_type = adr_type;
1795   ace->_index    = idx;
1796   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
1797 
1798   // Might as well try to fill the cache for the flattened version, too.
1799   AliasCacheEntry* face = probe_alias_cache(flat);
1800   if (face->_adr_type == NULL) {
1801     face->_adr_type = flat;
1802     face->_index    = idx;
1803     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1804   }
1805 
1806   return alias_type(idx);
1807 }
1808 
1809 
1810 Compile::AliasType* Compile::alias_type(ciField* field) {
1811   const TypeOopPtr* t;
1812   if (field->is_static())
1813     t = TypeInstPtr::make(field->holder()->java_mirror());
1814   else
1815     t = TypeOopPtr::make_from_klass_raw(field->holder());
1816   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1817   assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
1818   return atp;
1819 }
1820 
1821 
1822 //------------------------------have_alias_type--------------------------------
1823 bool Compile::have_alias_type(const TypePtr* adr_type) {
1824   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1825   if (ace->_adr_type == adr_type) {
1826     return true;
1827   }
1828 
1829   // Handle special cases.
1830   if (adr_type == NULL)             return true;
1831   if (adr_type == TypePtr::BOTTOM)  return true;
1832 
1833   return find_alias_type(adr_type, true, NULL) != NULL;
1834 }
1835 
1836 //-----------------------------must_alias--------------------------------------
1837 // True if all values of the given address type are in the given alias category.
1838 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1839   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1840   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
1841   if (alias_idx == AliasIdxTop)         return false; // the empty category
1842   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1843 
1844   // the only remaining possible overlap is identity
1845   int adr_idx = get_alias_index(adr_type);
1846   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1847   assert(adr_idx == alias_idx ||
1848          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1849           && adr_type                       != TypeOopPtr::BOTTOM),
1850          "should not be testing for overlap with an unsafe pointer");
1851   return adr_idx == alias_idx;
1852 }
1853 
1854 //------------------------------can_alias--------------------------------------
1855 // True if any values of the given address type are in the given alias category.
1856 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1857   if (alias_idx == AliasIdxTop)         return false; // the empty category
1858   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
1859   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1860   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
1861 
1862   // the only remaining possible overlap is identity
1863   int adr_idx = get_alias_index(adr_type);
1864   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1865   return adr_idx == alias_idx;
1866 }
1867 
1868 
1869 
1870 //---------------------------pop_warm_call-------------------------------------
1871 WarmCallInfo* Compile::pop_warm_call() {
1872   WarmCallInfo* wci = _warm_calls;
1873   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
1874   return wci;
1875 }
1876 
1877 //----------------------------Inline_Warm--------------------------------------
1878 int Compile::Inline_Warm() {
1879   // If there is room, try to inline some more warm call sites.
1880   // %%% Do a graph index compaction pass when we think we're out of space?
1881   if (!InlineWarmCalls)  return 0;
1882 
1883   int calls_made_hot = 0;
1884   int room_to_grow   = NodeCountInliningCutoff - unique();
1885   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1886   int amount_grown   = 0;
1887   WarmCallInfo* call;
1888   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1889     int est_size = (int)call->size();
1890     if (est_size > (room_to_grow - amount_grown)) {
1891       // This one won't fit anyway.  Get rid of it.
1892       call->make_cold();
1893       continue;
1894     }
1895     call->make_hot();
1896     calls_made_hot++;
1897     amount_grown   += est_size;
1898     amount_to_grow -= est_size;
1899   }
1900 
1901   if (calls_made_hot > 0)  set_major_progress();
1902   return calls_made_hot;
1903 }
1904 
1905 
1906 //----------------------------Finish_Warm--------------------------------------
1907 void Compile::Finish_Warm() {
1908   if (!InlineWarmCalls)  return;
1909   if (failing())  return;
1910   if (warm_calls() == NULL)  return;
1911 
1912   // Clean up loose ends, if we are out of space for inlining.
1913   WarmCallInfo* call;
1914   while ((call = pop_warm_call()) != NULL) {
1915     call->make_cold();
1916   }
1917 }
1918 
1919 //---------------------cleanup_loop_predicates-----------------------
1920 // Remove the opaque nodes that protect the predicates so that all unused
1921 // checks and uncommon_traps will be eliminated from the ideal graph
1922 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1923   if (predicate_count()==0) return;
1924   for (int i = predicate_count(); i > 0; i--) {
1925     Node * n = predicate_opaque1_node(i-1);
1926     assert(n->Opcode() == Op_Opaque1, "must be");
1927     igvn.replace_node(n, n->in(1));
1928   }
1929   assert(predicate_count()==0, "should be clean!");
1930 }
1931 
1932 void Compile::add_range_check_cast(Node* n) {
1933   assert(n->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1934   assert(!_range_check_casts->contains(n), "duplicate entry in range check casts");
1935   _range_check_casts->append(n);
1936 }
1937 
1938 // Remove all range check dependent CastIINodes.
1939 void Compile::remove_range_check_casts(PhaseIterGVN &igvn) {
1940   for (int i = range_check_cast_count(); i > 0; i--) {
1941     Node* cast = range_check_cast_node(i-1);
1942     assert(cast->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1943     igvn.replace_node(cast, cast->in(1));
1944   }
1945   assert(range_check_cast_count() == 0, "should be empty");
1946 }
1947 
1948 // StringOpts and late inlining of string methods
1949 void Compile::inline_string_calls(bool parse_time) {
1950   {
1951     // remove useless nodes to make the usage analysis simpler
1952     ResourceMark rm;
1953     PhaseRemoveUseless pru(initial_gvn(), for_igvn());
1954   }
1955 
1956   {
1957     ResourceMark rm;
1958     print_method(PHASE_BEFORE_STRINGOPTS, 3);
1959     PhaseStringOpts pso(initial_gvn(), for_igvn());
1960     print_method(PHASE_AFTER_STRINGOPTS, 3);
1961   }
1962 
1963   // now inline anything that we skipped the first time around
1964   if (!parse_time) {
1965     _late_inlines_pos = _late_inlines.length();
1966   }
1967 
1968   while (_string_late_inlines.length() > 0) {
1969     CallGenerator* cg = _string_late_inlines.pop();
1970     cg->do_late_inline();
1971     if (failing())  return;
1972   }
1973   _string_late_inlines.trunc_to(0);
1974 }
1975 
1976 // Late inlining of boxing methods
1977 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
1978   if (_boxing_late_inlines.length() > 0) {
1979     assert(has_boxed_value(), "inconsistent");
1980 
1981     PhaseGVN* gvn = initial_gvn();
1982     set_inlining_incrementally(true);
1983 
1984     assert( igvn._worklist.size() == 0, "should be done with igvn" );
1985     for_igvn()->clear();
1986     gvn->replace_with(&igvn);
1987 
1988     _late_inlines_pos = _late_inlines.length();
1989 
1990     while (_boxing_late_inlines.length() > 0) {
1991       CallGenerator* cg = _boxing_late_inlines.pop();
1992       cg->do_late_inline();
1993       if (failing())  return;
1994     }
1995     _boxing_late_inlines.trunc_to(0);
1996 
1997     {
1998       ResourceMark rm;
1999       PhaseRemoveUseless pru(gvn, for_igvn());
2000     }
2001 
2002     igvn = PhaseIterGVN(gvn);
2003     igvn.optimize();
2004 
2005     set_inlining_progress(false);
2006     set_inlining_incrementally(false);
2007   }
2008 }
2009 
2010 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
2011   assert(IncrementalInline, "incremental inlining should be on");
2012   PhaseGVN* gvn = initial_gvn();
2013 
2014   set_inlining_progress(false);
2015   for_igvn()->clear();
2016   gvn->replace_with(&igvn);
2017 
2018   int i = 0;
2019 
2020   for (; i <_late_inlines.length() && !inlining_progress(); i++) {
2021     CallGenerator* cg = _late_inlines.at(i);
2022     _late_inlines_pos = i+1;
2023     cg->do_late_inline();
2024     if (failing())  return;
2025   }
2026   int j = 0;
2027   for (; i < _late_inlines.length(); i++, j++) {
2028     _late_inlines.at_put(j, _late_inlines.at(i));
2029   }
2030   _late_inlines.trunc_to(j);
2031 
2032   {
2033     ResourceMark rm;
2034     PhaseRemoveUseless pru(gvn, for_igvn());
2035   }
2036 
2037   igvn = PhaseIterGVN(gvn);
2038 }
2039 
2040 // Perform incremental inlining until bound on number of live nodes is reached
2041 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
2042   PhaseGVN* gvn = initial_gvn();
2043 
2044   set_inlining_incrementally(true);
2045   set_inlining_progress(true);
2046   uint low_live_nodes = 0;
2047 
2048   while(inlining_progress() && _late_inlines.length() > 0) {
2049 
2050     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2051       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
2052         // PhaseIdealLoop is expensive so we only try it once we are
2053         // out of live nodes and we only try it again if the previous
2054         // helped got the number of nodes down significantly
2055         PhaseIdealLoop ideal_loop( igvn, false, true );
2056         if (failing())  return;
2057         low_live_nodes = live_nodes();
2058         _major_progress = true;
2059       }
2060 
2061       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2062         break;
2063       }
2064     }
2065 
2066     inline_incrementally_one(igvn);
2067 
2068     if (failing())  return;
2069 
2070     igvn.optimize();
2071 
2072     if (failing())  return;
2073   }
2074 
2075   assert( igvn._worklist.size() == 0, "should be done with igvn" );
2076 
2077   if (_string_late_inlines.length() > 0) {
2078     assert(has_stringbuilder(), "inconsistent");
2079     for_igvn()->clear();
2080     initial_gvn()->replace_with(&igvn);
2081 
2082     inline_string_calls(false);
2083 
2084     if (failing())  return;
2085 
2086     {
2087       ResourceMark rm;
2088       PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2089     }
2090 
2091     igvn = PhaseIterGVN(gvn);
2092 
2093     igvn.optimize();
2094   }
2095 
2096   set_inlining_incrementally(false);
2097 }
2098 
2099 
2100 // Remove edges from "root" to each SafePoint at a backward branch.
2101 // They were inserted during parsing (see add_safepoint()) to make
2102 // infinite loops without calls or exceptions visible to root, i.e.,
2103 // useful.
2104 void Compile::remove_root_to_sfpts_edges() {
2105   Node *r = root();
2106   if (r != NULL) {
2107     for (uint i = r->req(); i < r->len(); ++i) {
2108       Node *n = r->in(i);
2109       if (n != NULL && n->is_SafePoint()) {
2110         r->rm_prec(i);
2111         --i;
2112       }
2113     }
2114   }
2115 }
2116 
2117 //------------------------------Optimize---------------------------------------
2118 // Given a graph, optimize it.
2119 void Compile::Optimize() {
2120   TracePhase t1("optimizer", &_t_optimizer, true);
2121 
2122 #ifndef PRODUCT
2123   if (env()->break_at_compile()) {
2124     BREAKPOINT;
2125   }
2126 
2127 #endif
2128 
2129   ResourceMark rm;
2130   int          loop_opts_cnt;
2131 
2132   NOT_PRODUCT( verify_graph_edges(); )
2133 
2134   print_method(PHASE_AFTER_PARSING);
2135 
2136  {
2137   // Iterative Global Value Numbering, including ideal transforms
2138   // Initialize IterGVN with types and values from parse-time GVN
2139   PhaseIterGVN igvn(initial_gvn());
2140   {
2141     NOT_PRODUCT( TracePhase t2("iterGVN", &_t_iterGVN, TimeCompiler); )
2142     igvn.optimize();
2143   }
2144 
2145   print_method(PHASE_ITER_GVN1, 2);
2146 
2147   if (failing())  return;
2148 
2149   {
2150     NOT_PRODUCT( TracePhase t2("incrementalInline", &_t_incrInline, TimeCompiler); )
2151     inline_incrementally(igvn);
2152   }
2153 
2154   print_method(PHASE_INCREMENTAL_INLINE, 2);
2155 
2156   if (failing())  return;
2157 
2158   if (eliminate_boxing()) {
2159     NOT_PRODUCT( TracePhase t2("incrementalInline", &_t_incrInline, TimeCompiler); )
2160     // Inline valueOf() methods now.
2161     inline_boxing_calls(igvn);
2162 
2163     if (AlwaysIncrementalInline) {
2164       inline_incrementally(igvn);
2165     }
2166 
2167     print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
2168 
2169     if (failing())  return;
2170   }
2171 
2172   // Now that all inlining is over, cut edge from root to loop
2173   // safepoints
2174   remove_root_to_sfpts_edges();
2175 
2176   // Remove the speculative part of types and clean up the graph from
2177   // the extra CastPP nodes whose only purpose is to carry them. Do
2178   // that early so that optimizations are not disrupted by the extra
2179   // CastPP nodes.
2180   remove_speculative_types(igvn);
2181 
2182   // No more new expensive nodes will be added to the list from here
2183   // so keep only the actual candidates for optimizations.
2184   cleanup_expensive_nodes(igvn);
2185 
2186   if (!failing() && RenumberLiveNodes && live_nodes() + NodeLimitFudgeFactor < unique()) {
2187     NOT_PRODUCT(Compile::TracePhase t2("", &_t_renumberLive, TimeCompiler);)
2188     initial_gvn()->replace_with(&igvn);
2189     for_igvn()->clear();
2190     Unique_Node_List new_worklist(C->comp_arena());
2191     {
2192       ResourceMark rm;
2193       PhaseRenumberLive prl = PhaseRenumberLive(initial_gvn(), for_igvn(), &new_worklist);
2194     }
2195     set_for_igvn(&new_worklist);
2196     igvn = PhaseIterGVN(initial_gvn());
2197     igvn.optimize();
2198   }
2199 
2200   // Perform escape analysis
2201   if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
2202     if (has_loops()) {
2203       // Cleanup graph (remove dead nodes).
2204       TracePhase t2("idealLoop", &_t_idealLoop, true);
2205       PhaseIdealLoop ideal_loop( igvn, false, true );
2206       if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
2207       if (failing())  return;
2208     }
2209     ConnectionGraph::do_analysis(this, &igvn);
2210 
2211     if (failing())  return;
2212 
2213     // Optimize out fields loads from scalar replaceable allocations.
2214     igvn.optimize();
2215     print_method(PHASE_ITER_GVN_AFTER_EA, 2);
2216 
2217     if (failing())  return;
2218 
2219     if (congraph() != NULL && macro_count() > 0) {
2220       NOT_PRODUCT( TracePhase t2("macroEliminate", &_t_macroEliminate, TimeCompiler); )
2221       PhaseMacroExpand mexp(igvn);
2222       mexp.eliminate_macro_nodes();
2223       igvn.set_delay_transform(false);
2224 
2225       igvn.optimize();
2226       print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
2227 
2228       if (failing())  return;
2229     }
2230   }
2231 
2232   // Loop transforms on the ideal graph.  Range Check Elimination,
2233   // peeling, unrolling, etc.
2234 
2235   // Set loop opts counter
2236   loop_opts_cnt = num_loop_opts();
2237   if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
2238     {
2239       TracePhase t2("idealLoop", &_t_idealLoop, true);
2240       PhaseIdealLoop ideal_loop( igvn, true );
2241       loop_opts_cnt--;
2242       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
2243       if (failing())  return;
2244     }
2245     // Loop opts pass if partial peeling occurred in previous pass
2246     if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
2247       TracePhase t3("idealLoop", &_t_idealLoop, true);
2248       PhaseIdealLoop ideal_loop( igvn, false );
2249       loop_opts_cnt--;
2250       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
2251       if (failing())  return;
2252     }
2253     // Loop opts pass for loop-unrolling before CCP
2254     if(major_progress() && (loop_opts_cnt > 0)) {
2255       TracePhase t4("idealLoop", &_t_idealLoop, true);
2256       PhaseIdealLoop ideal_loop( igvn, false );
2257       loop_opts_cnt--;
2258       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
2259     }
2260     if (!failing()) {
2261       // Verify that last round of loop opts produced a valid graph
2262       NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
2263       PhaseIdealLoop::verify(igvn);
2264     }
2265   }
2266   if (failing())  return;
2267 
2268   // Conditional Constant Propagation;
2269   PhaseCCP ccp( &igvn );
2270   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
2271   {
2272     TracePhase t2("ccp", &_t_ccp, true);
2273     ccp.do_transform();
2274   }
2275   print_method(PHASE_CPP1, 2);
2276 
2277   assert( true, "Break here to ccp.dump_old2new_map()");
2278 
2279   // Iterative Global Value Numbering, including ideal transforms
2280   {
2281     NOT_PRODUCT( TracePhase t2("iterGVN2", &_t_iterGVN2, TimeCompiler); )
2282     igvn = ccp;
2283     igvn.optimize();
2284   }
2285 
2286   print_method(PHASE_ITER_GVN2, 2);
2287 
2288   if (failing())  return;
2289 
2290   // Loop transforms on the ideal graph.  Range Check Elimination,
2291   // peeling, unrolling, etc.
2292   if(loop_opts_cnt > 0) {
2293     debug_only( int cnt = 0; );
2294     while(major_progress() && (loop_opts_cnt > 0)) {
2295       TracePhase t2("idealLoop", &_t_idealLoop, true);
2296       assert( cnt++ < 40, "infinite cycle in loop optimization" );
2297       PhaseIdealLoop ideal_loop( igvn, true);
2298       loop_opts_cnt--;
2299       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
2300       if (failing())  return;
2301     }
2302   }
2303 
2304   {
2305     // Verify that all previous optimizations produced a valid graph
2306     // at least to this point, even if no loop optimizations were done.
2307     NOT_PRODUCT( TracePhase t2("idealLoopVerify", &_t_idealLoopVerify, TimeCompiler); )
2308     PhaseIdealLoop::verify(igvn);
2309   }
2310 
2311   if (range_check_cast_count() > 0) {
2312     // No more loop optimizations. Remove all range check dependent CastIINodes.
2313     C->remove_range_check_casts(igvn);
2314     igvn.optimize();
2315   }
2316 
2317 #ifdef ASSERT
2318   if (UseShenandoahGC && ShenandoahVerifyOptoBarriers) {
2319     ShenandoahBarrierC2Support::verify(C->root());
2320   }
2321 #endif
2322 
2323   {
2324     NOT_PRODUCT( TracePhase t2("macroExpand", &_t_macroExpand, TimeCompiler); )
2325     PhaseMacroExpand  mex(igvn);
2326     if (mex.expand_macro_nodes()) {
2327       assert(failing(), "must bail out w/ explicit message");
2328       return;
2329     }
2330   }
2331 
2332 #if INCLUDE_ALL_GCS
2333   if (UseShenandoahGC) {
2334     ShenandoahBarrierC2Support::expand(this, igvn);
2335   }
2336 #endif
2337 
2338  } // (End scope of igvn; run destructor if necessary for asserts.)
2339 
2340   dump_inlining();
2341   // A method with only infinite loops has no edges entering loops from root
2342   {
2343     NOT_PRODUCT( TracePhase t2("graphReshape", &_t_graphReshaping, TimeCompiler); )
2344     if (final_graph_reshaping()) {
2345       assert(failing(), "must bail out w/ explicit message");
2346       return;
2347     }
2348   }
2349 
2350   print_method(PHASE_OPTIMIZE_FINISHED, 2);
2351 }
2352 
2353 
2354 //------------------------------Code_Gen---------------------------------------
2355 // Given a graph, generate code for it
2356 void Compile::Code_Gen() {
2357   if (failing()) {
2358     return;
2359   }
2360 
2361   // Perform instruction selection.  You might think we could reclaim Matcher
2362   // memory PDQ, but actually the Matcher is used in generating spill code.
2363   // Internals of the Matcher (including some VectorSets) must remain live
2364   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
2365   // set a bit in reclaimed memory.
2366 
2367   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2368   // nodes.  Mapping is only valid at the root of each matched subtree.
2369   NOT_PRODUCT( verify_graph_edges(); )
2370 
2371   Matcher matcher;
2372   _matcher = &matcher;
2373   {
2374     TracePhase t2("matcher", &_t_matcher, true);
2375     matcher.match();
2376   }
2377   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2378   // nodes.  Mapping is only valid at the root of each matched subtree.
2379   NOT_PRODUCT( verify_graph_edges(); )
2380 
2381   // If you have too many nodes, or if matching has failed, bail out
2382   check_node_count(0, "out of nodes matching instructions");
2383   if (failing()) {
2384     return;
2385   }
2386 
2387   // Build a proper-looking CFG
2388   PhaseCFG cfg(node_arena(), root(), matcher);
2389   _cfg = &cfg;
2390   {
2391     NOT_PRODUCT( TracePhase t2("scheduler", &_t_scheduler, TimeCompiler); )
2392     bool success = cfg.do_global_code_motion();
2393     if (!success) {
2394       return;
2395     }
2396 
2397     print_method(PHASE_GLOBAL_CODE_MOTION, 2);
2398     NOT_PRODUCT( verify_graph_edges(); )
2399     debug_only( cfg.verify(); )
2400   }
2401 
2402   PhaseChaitin regalloc(unique(), cfg, matcher);
2403   _regalloc = &regalloc;
2404   {
2405     TracePhase t2("regalloc", &_t_registerAllocation, true);
2406     // Perform register allocation.  After Chaitin, use-def chains are
2407     // no longer accurate (at spill code) and so must be ignored.
2408     // Node->LRG->reg mappings are still accurate.
2409     _regalloc->Register_Allocate();
2410 
2411     // Bail out if the allocator builds too many nodes
2412     if (failing()) {
2413       return;
2414     }
2415   }
2416 
2417   // Prior to register allocation we kept empty basic blocks in case the
2418   // the allocator needed a place to spill.  After register allocation we
2419   // are not adding any new instructions.  If any basic block is empty, we
2420   // can now safely remove it.
2421   {
2422     NOT_PRODUCT( TracePhase t2("blockOrdering", &_t_blockOrdering, TimeCompiler); )
2423     cfg.remove_empty_blocks();
2424     if (do_freq_based_layout()) {
2425       PhaseBlockLayout layout(cfg);
2426     } else {
2427       cfg.set_loop_alignment();
2428     }
2429     cfg.fixup_flow();
2430   }
2431 
2432   // Apply peephole optimizations
2433   if( OptoPeephole ) {
2434     NOT_PRODUCT( TracePhase t2("peephole", &_t_peephole, TimeCompiler); )
2435     PhasePeephole peep( _regalloc, cfg);
2436     peep.do_transform();
2437   }
2438 
2439   // Do late expand if CPU requires this.
2440   if (Matcher::require_postalloc_expand) {
2441     NOT_PRODUCT(TracePhase t2c("postalloc_expand", &_t_postalloc_expand, true));
2442     cfg.postalloc_expand(_regalloc);
2443   }
2444 
2445   // Convert Nodes to instruction bits in a buffer
2446   {
2447     // %%%% workspace merge brought two timers together for one job
2448     TracePhase t2a("output", &_t_output, true);
2449     NOT_PRODUCT( TraceTime t2b(NULL, &_t_codeGeneration, TimeCompiler, false); )
2450     Output();
2451   }
2452 
2453   print_method(PHASE_FINAL_CODE);
2454 
2455   // He's dead, Jim.
2456   _cfg     = (PhaseCFG*)((intptr_t)0xdeadbeef);
2457   _regalloc = (PhaseChaitin*)((intptr_t)0xdeadbeef);
2458 }
2459 
2460 
2461 //------------------------------dump_asm---------------------------------------
2462 // Dump formatted assembly
2463 #ifndef PRODUCT
2464 void Compile::dump_asm(int *pcs, uint pc_limit) {
2465   bool cut_short = false;
2466   tty->print_cr("#");
2467   tty->print("#  ");  _tf->dump();  tty->cr();
2468   tty->print_cr("#");
2469 
2470   // For all blocks
2471   int pc = 0x0;                 // Program counter
2472   char starts_bundle = ' ';
2473   _regalloc->dump_frame();
2474 
2475   Node *n = NULL;
2476   for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
2477     if (VMThread::should_terminate()) {
2478       cut_short = true;
2479       break;
2480     }
2481     Block* block = _cfg->get_block(i);
2482     if (block->is_connector() && !Verbose) {
2483       continue;
2484     }
2485     n = block->head();
2486     if (pcs && n->_idx < pc_limit) {
2487       tty->print("%3.3x   ", pcs[n->_idx]);
2488     } else {
2489       tty->print("      ");
2490     }
2491     block->dump_head(_cfg);
2492     if (block->is_connector()) {
2493       tty->print_cr("        # Empty connector block");
2494     } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
2495       tty->print_cr("        # Block is sole successor of call");
2496     }
2497 
2498     // For all instructions
2499     Node *delay = NULL;
2500     for (uint j = 0; j < block->number_of_nodes(); j++) {
2501       if (VMThread::should_terminate()) {
2502         cut_short = true;
2503         break;
2504       }
2505       n = block->get_node(j);
2506       if (valid_bundle_info(n)) {
2507         Bundle* bundle = node_bundling(n);
2508         if (bundle->used_in_unconditional_delay()) {
2509           delay = n;
2510           continue;
2511         }
2512         if (bundle->starts_bundle()) {
2513           starts_bundle = '+';
2514         }
2515       }
2516 
2517       if (WizardMode) {
2518         n->dump();
2519       }
2520 
2521       if( !n->is_Region() &&    // Dont print in the Assembly
2522           !n->is_Phi() &&       // a few noisely useless nodes
2523           !n->is_Proj() &&
2524           !n->is_MachTemp() &&
2525           !n->is_SafePointScalarObject() &&
2526           !n->is_Catch() &&     // Would be nice to print exception table targets
2527           !n->is_MergeMem() &&  // Not very interesting
2528           !n->is_top() &&       // Debug info table constants
2529           !(n->is_Con() && !n->is_Mach())// Debug info table constants
2530           ) {
2531         if (pcs && n->_idx < pc_limit)
2532           tty->print("%3.3x", pcs[n->_idx]);
2533         else
2534           tty->print("   ");
2535         tty->print(" %c ", starts_bundle);
2536         starts_bundle = ' ';
2537         tty->print("\t");
2538         n->format(_regalloc, tty);
2539         tty->cr();
2540       }
2541 
2542       // If we have an instruction with a delay slot, and have seen a delay,
2543       // then back up and print it
2544       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
2545         assert(delay != NULL, "no unconditional delay instruction");
2546         if (WizardMode) delay->dump();
2547 
2548         if (node_bundling(delay)->starts_bundle())
2549           starts_bundle = '+';
2550         if (pcs && n->_idx < pc_limit)
2551           tty->print("%3.3x", pcs[n->_idx]);
2552         else
2553           tty->print("   ");
2554         tty->print(" %c ", starts_bundle);
2555         starts_bundle = ' ';
2556         tty->print("\t");
2557         delay->format(_regalloc, tty);
2558         tty->cr();
2559         delay = NULL;
2560       }
2561 
2562       // Dump the exception table as well
2563       if( n->is_Catch() && (Verbose || WizardMode) ) {
2564         // Print the exception table for this offset
2565         _handler_table.print_subtable_for(pc);
2566       }
2567     }
2568 
2569     if (pcs && n->_idx < pc_limit)
2570       tty->print_cr("%3.3x", pcs[n->_idx]);
2571     else
2572       tty->cr();
2573 
2574     assert(cut_short || delay == NULL, "no unconditional delay branch");
2575 
2576   } // End of per-block dump
2577   tty->cr();
2578 
2579   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
2580 }
2581 #endif
2582 
2583 //------------------------------Final_Reshape_Counts---------------------------
2584 // This class defines counters to help identify when a method
2585 // may/must be executed using hardware with only 24-bit precision.
2586 struct Final_Reshape_Counts : public StackObj {
2587   int  _call_count;             // count non-inlined 'common' calls
2588   int  _float_count;            // count float ops requiring 24-bit precision
2589   int  _double_count;           // count double ops requiring more precision
2590   int  _java_call_count;        // count non-inlined 'java' calls
2591   int  _inner_loop_count;       // count loops which need alignment
2592   VectorSet _visited;           // Visitation flags
2593   Node_List _tests;             // Set of IfNodes & PCTableNodes
2594 
2595   Final_Reshape_Counts() :
2596     _call_count(0), _float_count(0), _double_count(0),
2597     _java_call_count(0), _inner_loop_count(0),
2598     _visited( Thread::current()->resource_area() ) { }
2599 
2600   void inc_call_count  () { _call_count  ++; }
2601   void inc_float_count () { _float_count ++; }
2602   void inc_double_count() { _double_count++; }
2603   void inc_java_call_count() { _java_call_count++; }
2604   void inc_inner_loop_count() { _inner_loop_count++; }
2605 
2606   int  get_call_count  () const { return _call_count  ; }
2607   int  get_float_count () const { return _float_count ; }
2608   int  get_double_count() const { return _double_count; }
2609   int  get_java_call_count() const { return _java_call_count; }
2610   int  get_inner_loop_count() const { return _inner_loop_count; }
2611 };
2612 
2613 #ifdef ASSERT
2614 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
2615   ciInstanceKlass *k = tp->klass()->as_instance_klass();
2616   // Make sure the offset goes inside the instance layout.
2617   return k->contains_field_offset(tp->offset());
2618   // Note that OffsetBot and OffsetTop are very negative.
2619 }
2620 #endif
2621 
2622 // Eliminate trivially redundant StoreCMs and accumulate their
2623 // precedence edges.
2624 void Compile::eliminate_redundant_card_marks(Node* n) {
2625   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
2626   if (n->in(MemNode::Address)->outcnt() > 1) {
2627     // There are multiple users of the same address so it might be
2628     // possible to eliminate some of the StoreCMs
2629     Node* mem = n->in(MemNode::Memory);
2630     Node* adr = n->in(MemNode::Address);
2631     Node* val = n->in(MemNode::ValueIn);
2632     Node* prev = n;
2633     bool done = false;
2634     // Walk the chain of StoreCMs eliminating ones that match.  As
2635     // long as it's a chain of single users then the optimization is
2636     // safe.  Eliminating partially redundant StoreCMs would require
2637     // cloning copies down the other paths.
2638     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
2639       if (adr == mem->in(MemNode::Address) &&
2640           val == mem->in(MemNode::ValueIn)) {
2641         // redundant StoreCM
2642         if (mem->req() > MemNode::OopStore) {
2643           // Hasn't been processed by this code yet.
2644           n->add_prec(mem->in(MemNode::OopStore));
2645         } else {
2646           // Already converted to precedence edge
2647           for (uint i = mem->req(); i < mem->len(); i++) {
2648             // Accumulate any precedence edges
2649             if (mem->in(i) != NULL) {
2650               n->add_prec(mem->in(i));
2651             }
2652           }
2653           // Everything above this point has been processed.
2654           done = true;
2655         }
2656         // Eliminate the previous StoreCM
2657         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
2658         assert(mem->outcnt() == 0, "should be dead");
2659         mem->disconnect_inputs(NULL, this);
2660       } else {
2661         prev = mem;
2662       }
2663       mem = prev->in(MemNode::Memory);
2664     }
2665   }
2666 }
2667 
2668 //------------------------------final_graph_reshaping_impl----------------------
2669 // Implement items 1-5 from final_graph_reshaping below.
2670 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
2671 
2672   if ( n->outcnt() == 0 ) return; // dead node
2673   uint nop = n->Opcode();
2674 
2675   // Check for 2-input instruction with "last use" on right input.
2676   // Swap to left input.  Implements item (2).
2677   if( n->req() == 3 &&          // two-input instruction
2678       n->in(1)->outcnt() > 1 && // left use is NOT a last use
2679       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
2680       n->in(2)->outcnt() == 1 &&// right use IS a last use
2681       !n->in(2)->is_Con() ) {   // right use is not a constant
2682     // Check for commutative opcode
2683     switch( nop ) {
2684     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
2685     case Op_MaxI:  case Op_MinI:
2686     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
2687     case Op_AndL:  case Op_XorL:  case Op_OrL:
2688     case Op_AndI:  case Op_XorI:  case Op_OrI: {
2689       // Move "last use" input to left by swapping inputs
2690       n->swap_edges(1, 2);
2691       break;
2692     }
2693     default:
2694       break;
2695     }
2696   }
2697 
2698 #ifdef ASSERT
2699   if( n->is_Mem() ) {
2700     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
2701     assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
2702             // oop will be recorded in oop map if load crosses safepoint
2703             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
2704                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
2705             "raw memory operations should have control edge");
2706   }
2707   if (n->is_MemBar()) {
2708     MemBarNode* mb = n->as_MemBar();
2709     if (mb->trailing_store() || mb->trailing_load_store()) {
2710       assert(mb->leading_membar()->trailing_membar() == mb, "bad membar pair");
2711       Node* mem = mb->in(MemBarNode::Precedent);
2712       assert((mb->trailing_store() && mem->is_Store() && mem->as_Store()->is_release()) ||
2713              (mb->trailing_load_store() && mem->is_LoadStore()), "missing mem op");
2714     } else if (mb->leading()) {
2715       assert(mb->trailing_membar()->leading_membar() == mb, "bad membar pair");
2716     }
2717   }
2718 #endif
2719   // Count FPU ops and common calls, implements item (3)
2720   switch( nop ) {
2721   // Count all float operations that may use FPU
2722   case Op_AddF:
2723   case Op_SubF:
2724   case Op_MulF:
2725   case Op_DivF:
2726   case Op_NegF:
2727   case Op_ModF:
2728   case Op_ConvI2F:
2729   case Op_ConF:
2730   case Op_CmpF:
2731   case Op_CmpF3:
2732   // case Op_ConvL2F: // longs are split into 32-bit halves
2733     frc.inc_float_count();
2734     break;
2735 
2736   case Op_ConvF2D:
2737   case Op_ConvD2F:
2738     frc.inc_float_count();
2739     frc.inc_double_count();
2740     break;
2741 
2742   // Count all double operations that may use FPU
2743   case Op_AddD:
2744   case Op_SubD:
2745   case Op_MulD:
2746   case Op_DivD:
2747   case Op_NegD:
2748   case Op_ModD:
2749   case Op_ConvI2D:
2750   case Op_ConvD2I:
2751   // case Op_ConvL2D: // handled by leaf call
2752   // case Op_ConvD2L: // handled by leaf call
2753   case Op_ConD:
2754   case Op_CmpD:
2755   case Op_CmpD3:
2756     frc.inc_double_count();
2757     break;
2758   case Op_Opaque1:              // Remove Opaque Nodes before matching
2759   case Op_Opaque2:              // Remove Opaque Nodes before matching
2760   case Op_Opaque3:
2761     n->subsume_by(n->in(1), this);
2762     break;
2763   case Op_CallStaticJava:
2764   case Op_CallJava:
2765   case Op_CallDynamicJava:
2766     frc.inc_java_call_count(); // Count java call site;
2767   case Op_CallRuntime:
2768   case Op_CallLeaf:
2769   case Op_CallLeafNoFP: {
2770     assert( n->is_Call(), "" );
2771     CallNode *call = n->as_Call();
2772     if (UseShenandoahGC && call->is_g1_wb_pre_call()) {
2773       uint cnt = OptoRuntime::g1_wb_pre_Type()->domain()->cnt();
2774       if (call->req() > cnt) {
2775         assert(call->req() == cnt+1, "only one extra input");
2776         Node* addp = call->in(cnt);
2777         assert(!CallLeafNode::has_only_g1_wb_pre_uses(addp), "useless address computation?");
2778         call->del_req(cnt);
2779       }
2780     }
2781     // Count call sites where the FP mode bit would have to be flipped.
2782     // Do not count uncommon runtime calls:
2783     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
2784     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
2785     if( !call->is_CallStaticJava() || !call->as_CallStaticJava()->_name ) {
2786       frc.inc_call_count();   // Count the call site
2787     } else {                  // See if uncommon argument is shared
2788       Node *n = call->in(TypeFunc::Parms);
2789       int nop = n->Opcode();
2790       // Clone shared simple arguments to uncommon calls, item (1).
2791       if( n->outcnt() > 1 &&
2792           !n->is_Proj() &&
2793           nop != Op_CreateEx &&
2794           nop != Op_CheckCastPP &&
2795           nop != Op_DecodeN &&
2796           nop != Op_DecodeNKlass &&
2797           !n->is_Mem() ) {
2798         Node *x = n->clone();
2799         call->set_req( TypeFunc::Parms, x );
2800       }
2801     }
2802     break;
2803   }
2804 
2805   case Op_StoreD:
2806   case Op_LoadD:
2807   case Op_LoadD_unaligned:
2808     frc.inc_double_count();
2809     goto handle_mem;
2810   case Op_StoreF:
2811   case Op_LoadF:
2812     frc.inc_float_count();
2813     goto handle_mem;
2814 
2815   case Op_StoreCM:
2816     {
2817       // Convert OopStore dependence into precedence edge
2818       Node* prec = n->in(MemNode::OopStore);
2819       n->del_req(MemNode::OopStore);
2820       n->add_prec(prec);
2821       eliminate_redundant_card_marks(n);
2822     }
2823 
2824     // fall through
2825 
2826   case Op_StoreB:
2827   case Op_StoreC:
2828   case Op_StorePConditional:
2829   case Op_StoreI:
2830   case Op_StoreL:
2831   case Op_StoreIConditional:
2832   case Op_StoreLConditional:
2833   case Op_CompareAndSwapI:
2834   case Op_CompareAndSwapL:
2835   case Op_CompareAndSwapP:
2836   case Op_CompareAndSwapN:
2837   case Op_GetAndAddI:
2838   case Op_GetAndAddL:
2839   case Op_GetAndSetI:
2840   case Op_GetAndSetL:
2841   case Op_GetAndSetP:
2842   case Op_GetAndSetN:
2843   case Op_StoreP:
2844   case Op_StoreN:
2845   case Op_StoreNKlass:
2846   case Op_LoadB:
2847   case Op_LoadUB:
2848   case Op_LoadUS:
2849   case Op_LoadI:
2850   case Op_LoadKlass:
2851   case Op_LoadNKlass:
2852   case Op_LoadL:
2853   case Op_LoadL_unaligned:
2854   case Op_LoadPLocked:
2855   case Op_LoadP:
2856   case Op_LoadN:
2857   case Op_LoadRange:
2858   case Op_LoadS: {
2859   handle_mem:
2860 #ifdef ASSERT
2861     if( VerifyOptoOopOffsets ) {
2862       assert( n->is_Mem(), "" );
2863       MemNode *mem  = (MemNode*)n;
2864       // Check to see if address types have grounded out somehow.
2865       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
2866       assert( !tp || oop_offset_is_sane(tp), "" );
2867     }
2868 #endif
2869     break;
2870   }
2871 
2872   case Op_AddP: {               // Assert sane base pointers
2873     Node *addp = n->in(AddPNode::Address);
2874     assert( !addp->is_AddP() ||
2875             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
2876             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
2877             "Base pointers must match" );
2878 #ifdef _LP64
2879     if ((UseCompressedOops || UseCompressedClassPointers) &&
2880         addp->Opcode() == Op_ConP &&
2881         addp == n->in(AddPNode::Base) &&
2882         n->in(AddPNode::Offset)->is_Con()) {
2883       // Use addressing with narrow klass to load with offset on x86.
2884       // On sparc loading 32-bits constant and decoding it have less
2885       // instructions (4) then load 64-bits constant (7).
2886       // Do this transformation here since IGVN will convert ConN back to ConP.
2887       const Type* t = addp->bottom_type();
2888       if (t->isa_oopptr() || t->isa_klassptr()) {
2889         Node* nn = NULL;
2890 
2891         int op = t->isa_oopptr() ? Op_ConN : Op_ConNKlass;
2892 
2893         // Look for existing ConN node of the same exact type.
2894         Node* r  = root();
2895         uint cnt = r->outcnt();
2896         for (uint i = 0; i < cnt; i++) {
2897           Node* m = r->raw_out(i);
2898           if (m!= NULL && m->Opcode() == op &&
2899               m->bottom_type()->make_ptr() == t) {
2900             nn = m;
2901             break;
2902           }
2903         }
2904         if (nn != NULL) {
2905           // Decode a narrow oop to match address
2906           // [R12 + narrow_oop_reg<<3 + offset]
2907           if (t->isa_oopptr()) {
2908             nn = new (this) DecodeNNode(nn, t);
2909           } else {
2910             nn = new (this) DecodeNKlassNode(nn, t);
2911           }
2912           n->set_req(AddPNode::Base, nn);
2913           n->set_req(AddPNode::Address, nn);
2914           if (addp->outcnt() == 0) {
2915             addp->disconnect_inputs(NULL, this);
2916           }
2917         }
2918       }
2919     }
2920 #endif
2921     break;
2922   }
2923 
2924   case Op_CastPP: {
2925     // Remove CastPP nodes to gain more freedom during scheduling but
2926     // keep the dependency they encode as control or precedence edges
2927     // (if control is set already) on memory operations. Some CastPP
2928     // nodes don't have a control (don't carry a dependency): skip
2929     // those.
2930     if (n->in(0) != NULL) {
2931       ResourceMark rm;
2932       Unique_Node_List wq;
2933       wq.push(n);
2934       for (uint next = 0; next < wq.size(); ++next) {
2935         Node *m = wq.at(next);
2936         for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
2937           Node* use = m->fast_out(i);
2938           if (use->is_Mem() || use->is_EncodeNarrowPtr() || use->Opcode() == Op_ShenandoahLoadReferenceBarrier) {
2939             use->ensure_control_or_add_prec(n->in(0));
2940           } else if (use->in(0) == NULL) {
2941             switch(use->Opcode()) {
2942             case Op_AddP:
2943             case Op_DecodeN:
2944             case Op_DecodeNKlass:
2945             case Op_CheckCastPP:
2946             case Op_CastPP:
2947               wq.push(use);
2948               break;
2949             }
2950           }
2951         }
2952       }
2953     }
2954     const bool is_LP64 = LP64_ONLY(true) NOT_LP64(false);
2955     if (is_LP64 && n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
2956       Node* in1 = n->in(1);
2957       const Type* t = n->bottom_type();
2958       Node* new_in1 = in1->clone();
2959       new_in1->as_DecodeN()->set_type(t);
2960 
2961       if (!Matcher::narrow_oop_use_complex_address()) {
2962         //
2963         // x86, ARM and friends can handle 2 adds in addressing mode
2964         // and Matcher can fold a DecodeN node into address by using
2965         // a narrow oop directly and do implicit NULL check in address:
2966         //
2967         // [R12 + narrow_oop_reg<<3 + offset]
2968         // NullCheck narrow_oop_reg
2969         //
2970         // On other platforms (Sparc) we have to keep new DecodeN node and
2971         // use it to do implicit NULL check in address:
2972         //
2973         // decode_not_null narrow_oop_reg, base_reg
2974         // [base_reg + offset]
2975         // NullCheck base_reg
2976         //
2977         // Pin the new DecodeN node to non-null path on these platform (Sparc)
2978         // to keep the information to which NULL check the new DecodeN node
2979         // corresponds to use it as value in implicit_null_check().
2980         //
2981         new_in1->set_req(0, n->in(0));
2982       }
2983 
2984       n->subsume_by(new_in1, this);
2985       if (in1->outcnt() == 0) {
2986         in1->disconnect_inputs(NULL, this);
2987       }
2988     } else {
2989       n->subsume_by(n->in(1), this);
2990       if (n->outcnt() == 0) {
2991         n->disconnect_inputs(NULL, this);
2992       }
2993     }
2994     break;
2995   }
2996 #ifdef _LP64
2997   case Op_CmpP:
2998     // Do this transformation here to preserve CmpPNode::sub() and
2999     // other TypePtr related Ideal optimizations (for example, ptr nullness).
3000     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
3001       Node* in1 = n->in(1);
3002       Node* in2 = n->in(2);
3003       if (!in1->is_DecodeNarrowPtr()) {
3004         in2 = in1;
3005         in1 = n->in(2);
3006       }
3007       assert(in1->is_DecodeNarrowPtr(), "sanity");
3008 
3009       Node* new_in2 = NULL;
3010       if (in2->is_DecodeNarrowPtr()) {
3011         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
3012         new_in2 = in2->in(1);
3013       } else if (in2->Opcode() == Op_ConP) {
3014         const Type* t = in2->bottom_type();
3015         if (t == TypePtr::NULL_PTR) {
3016           assert(in1->is_DecodeN(), "compare klass to null?");
3017           // Don't convert CmpP null check into CmpN if compressed
3018           // oops implicit null check is not generated.
3019           // This will allow to generate normal oop implicit null check.
3020           if (Matcher::gen_narrow_oop_implicit_null_checks())
3021             new_in2 = ConNode::make(this, TypeNarrowOop::NULL_PTR);
3022           //
3023           // This transformation together with CastPP transformation above
3024           // will generated code for implicit NULL checks for compressed oops.
3025           //
3026           // The original code after Optimize()
3027           //
3028           //    LoadN memory, narrow_oop_reg
3029           //    decode narrow_oop_reg, base_reg
3030           //    CmpP base_reg, NULL
3031           //    CastPP base_reg // NotNull
3032           //    Load [base_reg + offset], val_reg
3033           //
3034           // after these transformations will be
3035           //
3036           //    LoadN memory, narrow_oop_reg
3037           //    CmpN narrow_oop_reg, NULL
3038           //    decode_not_null narrow_oop_reg, base_reg
3039           //    Load [base_reg + offset], val_reg
3040           //
3041           // and the uncommon path (== NULL) will use narrow_oop_reg directly
3042           // since narrow oops can be used in debug info now (see the code in
3043           // final_graph_reshaping_walk()).
3044           //
3045           // At the end the code will be matched to
3046           // on x86:
3047           //
3048           //    Load_narrow_oop memory, narrow_oop_reg
3049           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
3050           //    NullCheck narrow_oop_reg
3051           //
3052           // and on sparc:
3053           //
3054           //    Load_narrow_oop memory, narrow_oop_reg
3055           //    decode_not_null narrow_oop_reg, base_reg
3056           //    Load [base_reg + offset], val_reg
3057           //    NullCheck base_reg
3058           //
3059         } else if (t->isa_oopptr()) {
3060           new_in2 = ConNode::make(this, t->make_narrowoop());
3061         } else if (t->isa_klassptr()) {
3062           new_in2 = ConNode::make(this, t->make_narrowklass());
3063         }
3064       }
3065       if (new_in2 != NULL) {
3066         Node* cmpN = new (this) CmpNNode(in1->in(1), new_in2);
3067         n->subsume_by(cmpN, this);
3068         if (in1->outcnt() == 0) {
3069           in1->disconnect_inputs(NULL, this);
3070         }
3071         if (in2->outcnt() == 0) {
3072           in2->disconnect_inputs(NULL, this);
3073         }
3074       }
3075     }
3076     break;
3077 
3078   case Op_DecodeN:
3079   case Op_DecodeNKlass:
3080     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
3081     // DecodeN could be pinned when it can't be fold into
3082     // an address expression, see the code for Op_CastPP above.
3083     assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
3084     break;
3085 
3086   case Op_EncodeP:
3087   case Op_EncodePKlass: {
3088     Node* in1 = n->in(1);
3089     if (in1->is_DecodeNarrowPtr()) {
3090       n->subsume_by(in1->in(1), this);
3091     } else if (in1->Opcode() == Op_ConP) {
3092       const Type* t = in1->bottom_type();
3093       if (t == TypePtr::NULL_PTR) {
3094         assert(t->isa_oopptr(), "null klass?");
3095         n->subsume_by(ConNode::make(this, TypeNarrowOop::NULL_PTR), this);
3096       } else if (t->isa_oopptr()) {
3097         n->subsume_by(ConNode::make(this, t->make_narrowoop()), this);
3098       } else if (t->isa_klassptr()) {
3099         n->subsume_by(ConNode::make(this, t->make_narrowklass()), this);
3100       }
3101     }
3102     if (in1->outcnt() == 0) {
3103       in1->disconnect_inputs(NULL, this);
3104     }
3105     break;
3106   }
3107 
3108   case Op_Proj: {
3109     if (OptimizeStringConcat) {
3110       ProjNode* p = n->as_Proj();
3111       if (p->_is_io_use) {
3112         // Separate projections were used for the exception path which
3113         // are normally removed by a late inline.  If it wasn't inlined
3114         // then they will hang around and should just be replaced with
3115         // the original one.
3116         Node* proj = NULL;
3117         // Replace with just one
3118         for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
3119           Node *use = i.get();
3120           if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
3121             proj = use;
3122             break;
3123           }
3124         }
3125         assert(proj != NULL || p->_con == TypeFunc::I_O, "io may be dropped at an infinite loop");
3126         if (proj != NULL) {
3127           p->subsume_by(proj, this);
3128         }
3129       }
3130     }
3131     break;
3132   }
3133 
3134   case Op_Phi:
3135     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
3136       // The EncodeP optimization may create Phi with the same edges
3137       // for all paths. It is not handled well by Register Allocator.
3138       Node* unique_in = n->in(1);
3139       assert(unique_in != NULL, "");
3140       uint cnt = n->req();
3141       for (uint i = 2; i < cnt; i++) {
3142         Node* m = n->in(i);
3143         assert(m != NULL, "");
3144         if (unique_in != m)
3145           unique_in = NULL;
3146       }
3147       if (unique_in != NULL) {
3148         n->subsume_by(unique_in, this);
3149       }
3150     }
3151     break;
3152 
3153 #endif
3154 
3155 #ifdef ASSERT
3156   case Op_CastII:
3157     // Verify that all range check dependent CastII nodes were removed.
3158     if (n->isa_CastII()->has_range_check()) {
3159       n->dump(3);
3160       assert(false, "Range check dependent CastII node was not removed");
3161     }
3162     break;
3163 #endif
3164 
3165   case Op_ModI:
3166     if (UseDivMod) {
3167       // Check if a%b and a/b both exist
3168       Node* d = n->find_similar(Op_DivI);
3169       if (d) {
3170         // Replace them with a fused divmod if supported
3171         if (Matcher::has_match_rule(Op_DivModI)) {
3172           DivModINode* divmod = DivModINode::make(this, n);
3173           d->subsume_by(divmod->div_proj(), this);
3174           n->subsume_by(divmod->mod_proj(), this);
3175         } else {
3176           // replace a%b with a-((a/b)*b)
3177           Node* mult = new (this) MulINode(d, d->in(2));
3178           Node* sub  = new (this) SubINode(d->in(1), mult);
3179           n->subsume_by(sub, this);
3180         }
3181       }
3182     }
3183     break;
3184 
3185   case Op_ModL:
3186     if (UseDivMod) {
3187       // Check if a%b and a/b both exist
3188       Node* d = n->find_similar(Op_DivL);
3189       if (d) {
3190         // Replace them with a fused divmod if supported
3191         if (Matcher::has_match_rule(Op_DivModL)) {
3192           DivModLNode* divmod = DivModLNode::make(this, n);
3193           d->subsume_by(divmod->div_proj(), this);
3194           n->subsume_by(divmod->mod_proj(), this);
3195         } else {
3196           // replace a%b with a-((a/b)*b)
3197           Node* mult = new (this) MulLNode(d, d->in(2));
3198           Node* sub  = new (this) SubLNode(d->in(1), mult);
3199           n->subsume_by(sub, this);
3200         }
3201       }
3202     }
3203     break;
3204 
3205   case Op_LoadVector:
3206   case Op_StoreVector:
3207     break;
3208 
3209   case Op_PackB:
3210   case Op_PackS:
3211   case Op_PackI:
3212   case Op_PackF:
3213   case Op_PackL:
3214   case Op_PackD:
3215     if (n->req()-1 > 2) {
3216       // Replace many operand PackNodes with a binary tree for matching
3217       PackNode* p = (PackNode*) n;
3218       Node* btp = p->binary_tree_pack(this, 1, n->req());
3219       n->subsume_by(btp, this);
3220     }
3221     break;
3222   case Op_Loop:
3223   case Op_CountedLoop:
3224     if (n->as_Loop()->is_inner_loop()) {
3225       frc.inc_inner_loop_count();
3226     }
3227     break;
3228   case Op_LShiftI:
3229   case Op_RShiftI:
3230   case Op_URShiftI:
3231   case Op_LShiftL:
3232   case Op_RShiftL:
3233   case Op_URShiftL:
3234     if (Matcher::need_masked_shift_count) {
3235       // The cpu's shift instructions don't restrict the count to the
3236       // lower 5/6 bits. We need to do the masking ourselves.
3237       Node* in2 = n->in(2);
3238       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
3239       const TypeInt* t = in2->find_int_type();
3240       if (t != NULL && t->is_con()) {
3241         juint shift = t->get_con();
3242         if (shift > mask) { // Unsigned cmp
3243           n->set_req(2, ConNode::make(this, TypeInt::make(shift & mask)));
3244         }
3245       } else {
3246         if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
3247           Node* shift = new (this) AndINode(in2, ConNode::make(this, TypeInt::make(mask)));
3248           n->set_req(2, shift);
3249         }
3250       }
3251       if (in2->outcnt() == 0) { // Remove dead node
3252         in2->disconnect_inputs(NULL, this);
3253       }
3254     }
3255     break;
3256   case Op_MemBarStoreStore:
3257   case Op_MemBarRelease:
3258     // Break the link with AllocateNode: it is no longer useful and
3259     // confuses register allocation.
3260     if (n->req() > MemBarNode::Precedent) {
3261       n->set_req(MemBarNode::Precedent, top());
3262     }
3263     break;
3264   case Op_ShenandoahLoadReferenceBarrier:
3265     assert(false, "should have been expanded already");
3266     break;
3267   default:
3268     assert( !n->is_Call(), "" );
3269     assert( !n->is_Mem(), "" );
3270     assert( nop != Op_ProfileBoolean, "should be eliminated during IGVN");
3271     break;
3272   }
3273 
3274   // Collect CFG split points
3275   if (n->is_MultiBranch())
3276     frc._tests.push(n);
3277 }
3278 
3279 //------------------------------final_graph_reshaping_walk---------------------
3280 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
3281 // requires that the walk visits a node's inputs before visiting the node.
3282 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
3283   ResourceArea *area = Thread::current()->resource_area();
3284   Unique_Node_List sfpt(area);
3285 
3286   frc._visited.set(root->_idx); // first, mark node as visited
3287   uint cnt = root->req();
3288   Node *n = root;
3289   uint  i = 0;
3290   while (true) {
3291     if (i < cnt) {
3292       // Place all non-visited non-null inputs onto stack
3293       Node* m = n->in(i);
3294       ++i;
3295       if (m != NULL && !frc._visited.test_set(m->_idx)) {
3296         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL) {
3297           // compute worst case interpreter size in case of a deoptimization
3298           update_interpreter_frame_size(m->as_SafePoint()->jvms()->interpreter_frame_size());
3299 
3300           sfpt.push(m);
3301         }
3302         cnt = m->req();
3303         nstack.push(n, i); // put on stack parent and next input's index
3304         n = m;
3305         i = 0;
3306       }
3307     } else {
3308       // Now do post-visit work
3309       final_graph_reshaping_impl( n, frc );
3310       if (nstack.is_empty())
3311         break;             // finished
3312       n = nstack.node();   // Get node from stack
3313       cnt = n->req();
3314       i = nstack.index();
3315       nstack.pop();        // Shift to the next node on stack
3316     }
3317   }
3318 
3319   // Skip next transformation if compressed oops are not used.
3320   if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
3321       (!UseCompressedOops && !UseCompressedClassPointers))
3322     return;
3323 
3324   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
3325   // It could be done for an uncommon traps or any safepoints/calls
3326   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
3327   while (sfpt.size() > 0) {
3328     n = sfpt.pop();
3329     JVMState *jvms = n->as_SafePoint()->jvms();
3330     assert(jvms != NULL, "sanity");
3331     int start = jvms->debug_start();
3332     int end   = n->req();
3333     bool is_uncommon = (n->is_CallStaticJava() &&
3334                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
3335     for (int j = start; j < end; j++) {
3336       Node* in = n->in(j);
3337       if (in->is_DecodeNarrowPtr()) {
3338         bool safe_to_skip = true;
3339         if (!is_uncommon ) {
3340           // Is it safe to skip?
3341           for (uint i = 0; i < in->outcnt(); i++) {
3342             Node* u = in->raw_out(i);
3343             if (!u->is_SafePoint() ||
3344                  u->is_Call() && u->as_Call()->has_non_debug_use(n)) {
3345               safe_to_skip = false;
3346             }
3347           }
3348         }
3349         if (safe_to_skip) {
3350           n->set_req(j, in->in(1));
3351         }
3352         if (in->outcnt() == 0) {
3353           in->disconnect_inputs(NULL, this);
3354         }
3355       }
3356     }
3357   }
3358 }
3359 
3360 //------------------------------final_graph_reshaping--------------------------
3361 // Final Graph Reshaping.
3362 //
3363 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
3364 //     and not commoned up and forced early.  Must come after regular
3365 //     optimizations to avoid GVN undoing the cloning.  Clone constant
3366 //     inputs to Loop Phis; these will be split by the allocator anyways.
3367 //     Remove Opaque nodes.
3368 // (2) Move last-uses by commutative operations to the left input to encourage
3369 //     Intel update-in-place two-address operations and better register usage
3370 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
3371 //     calls canonicalizing them back.
3372 // (3) Count the number of double-precision FP ops, single-precision FP ops
3373 //     and call sites.  On Intel, we can get correct rounding either by
3374 //     forcing singles to memory (requires extra stores and loads after each
3375 //     FP bytecode) or we can set a rounding mode bit (requires setting and
3376 //     clearing the mode bit around call sites).  The mode bit is only used
3377 //     if the relative frequency of single FP ops to calls is low enough.
3378 //     This is a key transform for SPEC mpeg_audio.
3379 // (4) Detect infinite loops; blobs of code reachable from above but not
3380 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
3381 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
3382 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
3383 //     Detection is by looking for IfNodes where only 1 projection is
3384 //     reachable from below or CatchNodes missing some targets.
3385 // (5) Assert for insane oop offsets in debug mode.
3386 
3387 bool Compile::final_graph_reshaping() {
3388   // an infinite loop may have been eliminated by the optimizer,
3389   // in which case the graph will be empty.
3390   if (root()->req() == 1) {
3391     record_method_not_compilable("trivial infinite loop");
3392     return true;
3393   }
3394 
3395   // Expensive nodes have their control input set to prevent the GVN
3396   // from freely commoning them. There's no GVN beyond this point so
3397   // no need to keep the control input. We want the expensive nodes to
3398   // be freely moved to the least frequent code path by gcm.
3399   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
3400   for (int i = 0; i < expensive_count(); i++) {
3401     _expensive_nodes->at(i)->set_req(0, NULL);
3402   }
3403 
3404   Final_Reshape_Counts frc;
3405 
3406   // Visit everybody reachable!
3407   // Allocate stack of size C->live_nodes()/2 to avoid frequent realloc
3408   Node_Stack nstack(live_nodes() >> 1);
3409   final_graph_reshaping_walk(nstack, root(), frc);
3410 
3411   // Check for unreachable (from below) code (i.e., infinite loops).
3412   for( uint i = 0; i < frc._tests.size(); i++ ) {
3413     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
3414     // Get number of CFG targets.
3415     // Note that PCTables include exception targets after calls.
3416     uint required_outcnt = n->required_outcnt();
3417     if (n->outcnt() != required_outcnt) {
3418       // Check for a few special cases.  Rethrow Nodes never take the
3419       // 'fall-thru' path, so expected kids is 1 less.
3420       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
3421         if (n->in(0)->in(0)->is_Call()) {
3422           CallNode *call = n->in(0)->in(0)->as_Call();
3423           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
3424             required_outcnt--;      // Rethrow always has 1 less kid
3425           } else if (call->req() > TypeFunc::Parms &&
3426                      call->is_CallDynamicJava()) {
3427             // Check for null receiver. In such case, the optimizer has
3428             // detected that the virtual call will always result in a null
3429             // pointer exception. The fall-through projection of this CatchNode
3430             // will not be populated.
3431             Node *arg0 = call->in(TypeFunc::Parms);
3432             if (arg0->is_Type() &&
3433                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
3434               required_outcnt--;
3435             }
3436           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
3437                      call->req() > TypeFunc::Parms+1 &&
3438                      call->is_CallStaticJava()) {
3439             // Check for negative array length. In such case, the optimizer has
3440             // detected that the allocation attempt will always result in an
3441             // exception. There is no fall-through projection of this CatchNode .
3442             Node *arg1 = call->in(TypeFunc::Parms+1);
3443             if (arg1->is_Type() &&
3444                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
3445               required_outcnt--;
3446             }
3447           }
3448         }
3449       }
3450       // Recheck with a better notion of 'required_outcnt'
3451       if (n->outcnt() != required_outcnt) {
3452         record_method_not_compilable("malformed control flow");
3453         return true;            // Not all targets reachable!
3454       }
3455     }
3456     // Check that I actually visited all kids.  Unreached kids
3457     // must be infinite loops.
3458     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
3459       if (!frc._visited.test(n->fast_out(j)->_idx)) {
3460         record_method_not_compilable("infinite loop");
3461         return true;            // Found unvisited kid; must be unreach
3462       }
3463   }
3464 
3465   // If original bytecodes contained a mixture of floats and doubles
3466   // check if the optimizer has made it homogenous, item (3).
3467   if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
3468       frc.get_float_count() > 32 &&
3469       frc.get_double_count() == 0 &&
3470       (10 * frc.get_call_count() < frc.get_float_count()) ) {
3471     set_24_bit_selection_and_mode( false,  true );
3472   }
3473 
3474   set_java_calls(frc.get_java_call_count());
3475   set_inner_loops(frc.get_inner_loop_count());
3476 
3477   // No infinite loops, no reason to bail out.
3478   return false;
3479 }
3480 
3481 //-----------------------------too_many_traps----------------------------------
3482 // Report if there are too many traps at the current method and bci.
3483 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
3484 bool Compile::too_many_traps(ciMethod* method,
3485                              int bci,
3486                              Deoptimization::DeoptReason reason) {
3487   ciMethodData* md = method->method_data();
3488   if (md->is_empty()) {
3489     // Assume the trap has not occurred, or that it occurred only
3490     // because of a transient condition during start-up in the interpreter.
3491     return false;
3492   }
3493   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3494   if (md->has_trap_at(bci, m, reason) != 0) {
3495     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
3496     // Also, if there are multiple reasons, or if there is no per-BCI record,
3497     // assume the worst.
3498     if (log())
3499       log()->elem("observe trap='%s' count='%d'",
3500                   Deoptimization::trap_reason_name(reason),
3501                   md->trap_count(reason));
3502     return true;
3503   } else {
3504     // Ignore method/bci and see if there have been too many globally.
3505     return too_many_traps(reason, md);
3506   }
3507 }
3508 
3509 // Less-accurate variant which does not require a method and bci.
3510 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
3511                              ciMethodData* logmd) {
3512   if (trap_count(reason) >= Deoptimization::per_method_trap_limit(reason)) {
3513     // Too many traps globally.
3514     // Note that we use cumulative trap_count, not just md->trap_count.
3515     if (log()) {
3516       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
3517       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
3518                   Deoptimization::trap_reason_name(reason),
3519                   mcount, trap_count(reason));
3520     }
3521     return true;
3522   } else {
3523     // The coast is clear.
3524     return false;
3525   }
3526 }
3527 
3528 //--------------------------too_many_recompiles--------------------------------
3529 // Report if there are too many recompiles at the current method and bci.
3530 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
3531 // Is not eager to return true, since this will cause the compiler to use
3532 // Action_none for a trap point, to avoid too many recompilations.
3533 bool Compile::too_many_recompiles(ciMethod* method,
3534                                   int bci,
3535                                   Deoptimization::DeoptReason reason) {
3536   ciMethodData* md = method->method_data();
3537   if (md->is_empty()) {
3538     // Assume the trap has not occurred, or that it occurred only
3539     // because of a transient condition during start-up in the interpreter.
3540     return false;
3541   }
3542   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
3543   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
3544   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
3545   Deoptimization::DeoptReason per_bc_reason
3546     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
3547   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3548   if ((per_bc_reason == Deoptimization::Reason_none
3549        || md->has_trap_at(bci, m, reason) != 0)
3550       // The trap frequency measure we care about is the recompile count:
3551       && md->trap_recompiled_at(bci, m)
3552       && md->overflow_recompile_count() >= bc_cutoff) {
3553     // Do not emit a trap here if it has already caused recompilations.
3554     // Also, if there are multiple reasons, or if there is no per-BCI record,
3555     // assume the worst.
3556     if (log())
3557       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
3558                   Deoptimization::trap_reason_name(reason),
3559                   md->trap_count(reason),
3560                   md->overflow_recompile_count());
3561     return true;
3562   } else if (trap_count(reason) != 0
3563              && decompile_count() >= m_cutoff) {
3564     // Too many recompiles globally, and we have seen this sort of trap.
3565     // Use cumulative decompile_count, not just md->decompile_count.
3566     if (log())
3567       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
3568                   Deoptimization::trap_reason_name(reason),
3569                   md->trap_count(reason), trap_count(reason),
3570                   md->decompile_count(), decompile_count());
3571     return true;
3572   } else {
3573     // The coast is clear.
3574     return false;
3575   }
3576 }
3577 
3578 // Compute when not to trap. Used by matching trap based nodes and
3579 // NullCheck optimization.
3580 void Compile::set_allowed_deopt_reasons() {
3581   _allowed_reasons = 0;
3582   if (is_method_compilation()) {
3583     for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
3584       assert(rs < BitsPerInt, "recode bit map");
3585       if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
3586         _allowed_reasons |= nth_bit(rs);
3587       }
3588     }
3589   }
3590 }
3591 
3592 #ifndef PRODUCT
3593 //------------------------------verify_graph_edges---------------------------
3594 // Walk the Graph and verify that there is a one-to-one correspondence
3595 // between Use-Def edges and Def-Use edges in the graph.
3596 void Compile::verify_graph_edges(bool no_dead_code) {
3597   if (VerifyGraphEdges) {
3598     ResourceArea *area = Thread::current()->resource_area();
3599     Unique_Node_List visited(area);
3600     // Call recursive graph walk to check edges
3601     _root->verify_edges(visited);
3602     if (no_dead_code) {
3603       // Now make sure that no visited node is used by an unvisited node.
3604       bool dead_nodes = false;
3605       Unique_Node_List checked(area);
3606       while (visited.size() > 0) {
3607         Node* n = visited.pop();
3608         checked.push(n);
3609         for (uint i = 0; i < n->outcnt(); i++) {
3610           Node* use = n->raw_out(i);
3611           if (checked.member(use))  continue;  // already checked
3612           if (visited.member(use))  continue;  // already in the graph
3613           if (use->is_Con())        continue;  // a dead ConNode is OK
3614           // At this point, we have found a dead node which is DU-reachable.
3615           if (!dead_nodes) {
3616             tty->print_cr("*** Dead nodes reachable via DU edges:");
3617             dead_nodes = true;
3618           }
3619           use->dump(2);
3620           tty->print_cr("---");
3621           checked.push(use);  // No repeats; pretend it is now checked.
3622         }
3623       }
3624       assert(!dead_nodes, "using nodes must be reachable from root");
3625     }
3626   }
3627 }
3628 
3629 // Verify GC barriers consistency
3630 // Currently supported:
3631 // - G1 pre-barriers (see GraphKit::g1_write_barrier_pre())
3632 void Compile::verify_barriers() {
3633   if (UseG1GC || UseShenandoahGC) {
3634     // Verify G1 pre-barriers
3635     const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + PtrQueue::byte_offset_of_active());
3636 
3637     ResourceArea *area = Thread::current()->resource_area();
3638     Unique_Node_List visited(area);
3639     Node_List worklist(area);
3640     // We're going to walk control flow backwards starting from the Root
3641     worklist.push(_root);
3642     while (worklist.size() > 0) {
3643       Node* x = worklist.pop();
3644       if (x == NULL || x == top()) continue;
3645       if (visited.member(x)) {
3646         continue;
3647       } else {
3648         visited.push(x);
3649       }
3650 
3651       if (x->is_Region()) {
3652         for (uint i = 1; i < x->req(); i++) {
3653           worklist.push(x->in(i));
3654         }
3655       } else {
3656         worklist.push(x->in(0));
3657         // We are looking for the pattern:
3658         //                            /->ThreadLocal
3659         // If->Bool->CmpI->LoadB->AddP->ConL(marking_offset)
3660         //              \->ConI(0)
3661         // We want to verify that the If and the LoadB have the same control
3662         // See GraphKit::g1_write_barrier_pre()
3663         if (x->is_If()) {
3664           IfNode *iff = x->as_If();
3665           if (iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) {
3666             CmpNode *cmp = iff->in(1)->in(1)->as_Cmp();
3667             if (cmp->Opcode() == Op_CmpI && cmp->in(2)->is_Con() && cmp->in(2)->bottom_type()->is_int()->get_con() == 0
3668                 && cmp->in(1)->is_Load()) {
3669               LoadNode* load = cmp->in(1)->as_Load();
3670               if (load->Opcode() == Op_LoadB && load->in(2)->is_AddP() && load->in(2)->in(2)->Opcode() == Op_ThreadLocal
3671                   && load->in(2)->in(3)->is_Con()
3672                   && load->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == marking_offset) {
3673 
3674                 Node* if_ctrl = iff->in(0);
3675                 Node* load_ctrl = load->in(0);
3676 
3677                 if (if_ctrl != load_ctrl) {
3678                   // Skip possible CProj->NeverBranch in infinite loops
3679                   if ((if_ctrl->is_Proj() && if_ctrl->Opcode() == Op_CProj)
3680                       && (if_ctrl->in(0)->is_MultiBranch() && if_ctrl->in(0)->Opcode() == Op_NeverBranch)) {
3681                     if_ctrl = if_ctrl->in(0)->in(0);
3682                   }
3683                 }
3684                 assert(load_ctrl != NULL && if_ctrl == load_ctrl, "controls must match");
3685               }
3686             }
3687           }
3688         }
3689       }
3690     }
3691   }
3692 }
3693 
3694 #endif
3695 
3696 // The Compile object keeps track of failure reasons separately from the ciEnv.
3697 // This is required because there is not quite a 1-1 relation between the
3698 // ciEnv and its compilation task and the Compile object.  Note that one
3699 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
3700 // to backtrack and retry without subsuming loads.  Other than this backtracking
3701 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
3702 // by the logic in C2Compiler.
3703 void Compile::record_failure(const char* reason) {
3704   if (log() != NULL) {
3705     log()->elem("failure reason='%s' phase='compile'", reason);
3706   }
3707   if (_failure_reason == NULL) {
3708     // Record the first failure reason.
3709     _failure_reason = reason;
3710   }
3711 
3712   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
3713     C->print_method(PHASE_FAILURE);
3714   }
3715   _root = NULL;  // flush the graph, too
3716 }
3717 
3718 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator, bool dolog)
3719   : TraceTime(NULL, accumulator, false NOT_PRODUCT( || TimeCompiler ), false),
3720     _phase_name(name), _dolog(dolog)
3721 {
3722   if (dolog) {
3723     C = Compile::current();
3724     _log = C->log();
3725   } else {
3726     C = NULL;
3727     _log = NULL;
3728   }
3729   if (_log != NULL) {
3730     _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3731     _log->stamp();
3732     _log->end_head();
3733   }
3734 }
3735 
3736 Compile::TracePhase::~TracePhase() {
3737 
3738   C = Compile::current();
3739   if (_dolog) {
3740     _log = C->log();
3741   } else {
3742     _log = NULL;
3743   }
3744 
3745 #ifdef ASSERT
3746   if (PrintIdealNodeCount) {
3747     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
3748                   _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
3749   }
3750 
3751   if (VerifyIdealNodeCount) {
3752     Compile::current()->print_missing_nodes();
3753   }
3754 #endif
3755 
3756   if (_log != NULL) {
3757     _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3758   }
3759 }
3760 
3761 //=============================================================================
3762 // Two Constant's are equal when the type and the value are equal.
3763 bool Compile::Constant::operator==(const Constant& other) {
3764   if (type()          != other.type()         )  return false;
3765   if (can_be_reused() != other.can_be_reused())  return false;
3766   // For floating point values we compare the bit pattern.
3767   switch (type()) {
3768   case T_FLOAT:   return (_v._value.i == other._v._value.i);
3769   case T_LONG:
3770   case T_DOUBLE:  return (_v._value.j == other._v._value.j);
3771   case T_OBJECT:
3772   case T_ADDRESS: return (_v._value.l == other._v._value.l);
3773   case T_VOID:    return (_v._value.l == other._v._value.l);  // jump-table entries
3774   case T_METADATA: return (_v._metadata == other._v._metadata);
3775   default: ShouldNotReachHere();
3776   }
3777   return false;
3778 }
3779 
3780 static int type_to_size_in_bytes(BasicType t) {
3781   switch (t) {
3782   case T_LONG:    return sizeof(jlong  );
3783   case T_FLOAT:   return sizeof(jfloat );
3784   case T_DOUBLE:  return sizeof(jdouble);
3785   case T_METADATA: return sizeof(Metadata*);
3786     // We use T_VOID as marker for jump-table entries (labels) which
3787     // need an internal word relocation.
3788   case T_VOID:
3789   case T_ADDRESS:
3790   case T_OBJECT:  return sizeof(jobject);
3791   }
3792 
3793   ShouldNotReachHere();
3794   return -1;
3795 }
3796 
3797 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
3798   // sort descending
3799   if (a->freq() > b->freq())  return -1;
3800   if (a->freq() < b->freq())  return  1;
3801   return 0;
3802 }
3803 
3804 void Compile::ConstantTable::calculate_offsets_and_size() {
3805   // First, sort the array by frequencies.
3806   _constants.sort(qsort_comparator);
3807 
3808 #ifdef ASSERT
3809   // Make sure all jump-table entries were sorted to the end of the
3810   // array (they have a negative frequency).
3811   bool found_void = false;
3812   for (int i = 0; i < _constants.length(); i++) {
3813     Constant con = _constants.at(i);
3814     if (con.type() == T_VOID)
3815       found_void = true;  // jump-tables
3816     else
3817       assert(!found_void, "wrong sorting");
3818   }
3819 #endif
3820 
3821   int offset = 0;
3822   for (int i = 0; i < _constants.length(); i++) {
3823     Constant* con = _constants.adr_at(i);
3824 
3825     // Align offset for type.
3826     int typesize = type_to_size_in_bytes(con->type());
3827     offset = align_size_up(offset, typesize);
3828     con->set_offset(offset);   // set constant's offset
3829 
3830     if (con->type() == T_VOID) {
3831       MachConstantNode* n = (MachConstantNode*) con->get_jobject();
3832       offset = offset + typesize * n->outcnt();  // expand jump-table
3833     } else {
3834       offset = offset + typesize;
3835     }
3836   }
3837 
3838   // Align size up to the next section start (which is insts; see
3839   // CodeBuffer::align_at_start).
3840   assert(_size == -1, "already set?");
3841   _size = align_size_up(offset, CodeEntryAlignment);
3842 }
3843 
3844 void Compile::ConstantTable::emit(CodeBuffer& cb) {
3845   MacroAssembler _masm(&cb);
3846   for (int i = 0; i < _constants.length(); i++) {
3847     Constant con = _constants.at(i);
3848     address constant_addr = NULL;
3849     switch (con.type()) {
3850     case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
3851     case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
3852     case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
3853     case T_OBJECT: {
3854       jobject obj = con.get_jobject();
3855       int oop_index = _masm.oop_recorder()->find_index(obj);
3856       constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
3857       break;
3858     }
3859     case T_ADDRESS: {
3860       address addr = (address) con.get_jobject();
3861       constant_addr = _masm.address_constant(addr);
3862       break;
3863     }
3864     // We use T_VOID as marker for jump-table entries (labels) which
3865     // need an internal word relocation.
3866     case T_VOID: {
3867       MachConstantNode* n = (MachConstantNode*) con.get_jobject();
3868       // Fill the jump-table with a dummy word.  The real value is
3869       // filled in later in fill_jump_table.
3870       address dummy = (address) n;
3871       constant_addr = _masm.address_constant(dummy);
3872       // Expand jump-table
3873       for (uint i = 1; i < n->outcnt(); i++) {
3874         address temp_addr = _masm.address_constant(dummy + i);
3875         assert(temp_addr, "consts section too small");
3876       }
3877       break;
3878     }
3879     case T_METADATA: {
3880       Metadata* obj = con.get_metadata();
3881       int metadata_index = _masm.oop_recorder()->find_index(obj);
3882       constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
3883       break;
3884     }
3885     default: ShouldNotReachHere();
3886     }
3887     assert(constant_addr, "consts section too small");
3888     assert((constant_addr - _masm.code()->consts()->start()) == con.offset(),
3889             err_msg_res("must be: %d == %d", (int) (constant_addr - _masm.code()->consts()->start()), (int)(con.offset())));
3890   }
3891 }
3892 
3893 int Compile::ConstantTable::find_offset(Constant& con) const {
3894   int idx = _constants.find(con);
3895   assert(idx != -1, "constant must be in constant table");
3896   int offset = _constants.at(idx).offset();
3897   assert(offset != -1, "constant table not emitted yet?");
3898   return offset;
3899 }
3900 
3901 void Compile::ConstantTable::add(Constant& con) {
3902   if (con.can_be_reused()) {
3903     int idx = _constants.find(con);
3904     if (idx != -1 && _constants.at(idx).can_be_reused()) {
3905       _constants.adr_at(idx)->inc_freq(con.freq());  // increase the frequency by the current value
3906       return;
3907     }
3908   }
3909   (void) _constants.append(con);
3910 }
3911 
3912 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
3913   Block* b = Compile::current()->cfg()->get_block_for_node(n);
3914   Constant con(type, value, b->_freq);
3915   add(con);
3916   return con;
3917 }
3918 
3919 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
3920   Constant con(metadata);
3921   add(con);
3922   return con;
3923 }
3924 
3925 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
3926   jvalue value;
3927   BasicType type = oper->type()->basic_type();
3928   switch (type) {
3929   case T_LONG:    value.j = oper->constantL(); break;
3930   case T_FLOAT:   value.f = oper->constantF(); break;
3931   case T_DOUBLE:  value.d = oper->constantD(); break;
3932   case T_OBJECT:
3933   case T_ADDRESS: value.l = (jobject) oper->constant(); break;
3934   case T_METADATA: return add((Metadata*)oper->constant()); break;
3935   default: guarantee(false, err_msg_res("unhandled type: %s", type2name(type)));
3936   }
3937   return add(n, type, value);
3938 }
3939 
3940 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
3941   jvalue value;
3942   // We can use the node pointer here to identify the right jump-table
3943   // as this method is called from Compile::Fill_buffer right before
3944   // the MachNodes are emitted and the jump-table is filled (means the
3945   // MachNode pointers do not change anymore).
3946   value.l = (jobject) n;
3947   Constant con(T_VOID, value, next_jump_table_freq(), false);  // Labels of a jump-table cannot be reused.
3948   add(con);
3949   return con;
3950 }
3951 
3952 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
3953   // If called from Compile::scratch_emit_size do nothing.
3954   if (Compile::current()->in_scratch_emit_size())  return;
3955 
3956   assert(labels.is_nonempty(), "must be");
3957   assert((uint) labels.length() == n->outcnt(), err_msg_res("must be equal: %d == %d", labels.length(), n->outcnt()));
3958 
3959   // Since MachConstantNode::constant_offset() also contains
3960   // table_base_offset() we need to subtract the table_base_offset()
3961   // to get the plain offset into the constant table.
3962   int offset = n->constant_offset() - table_base_offset();
3963 
3964   MacroAssembler _masm(&cb);
3965   address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
3966 
3967   for (uint i = 0; i < n->outcnt(); i++) {
3968     address* constant_addr = &jump_table_base[i];
3969     assert(*constant_addr == (((address) n) + i), err_msg_res("all jump-table entries must contain adjusted node pointer: " INTPTR_FORMAT " == " INTPTR_FORMAT, p2i(*constant_addr), p2i(((address) n) + i)));
3970     *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
3971     cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
3972   }
3973 }
3974 
3975 void Compile::dump_inlining() {
3976   if (print_inlining() || print_intrinsics()) {
3977     // Print inlining message for candidates that we couldn't inline
3978     // for lack of space or non constant receiver
3979     for (int i = 0; i < _late_inlines.length(); i++) {
3980       CallGenerator* cg = _late_inlines.at(i);
3981       cg->print_inlining_late("live nodes > LiveNodeCountInliningCutoff");
3982     }
3983     Unique_Node_List useful;
3984     useful.push(root());
3985     for (uint next = 0; next < useful.size(); ++next) {
3986       Node* n  = useful.at(next);
3987       if (n->is_Call() && n->as_Call()->generator() != NULL && n->as_Call()->generator()->call_node() == n) {
3988         CallNode* call = n->as_Call();
3989         CallGenerator* cg = call->generator();
3990         cg->print_inlining_late("receiver not constant");
3991       }
3992       uint max = n->len();
3993       for ( uint i = 0; i < max; ++i ) {
3994         Node *m = n->in(i);
3995         if ( m == NULL ) continue;
3996         useful.push(m);
3997       }
3998     }
3999     for (int i = 0; i < _print_inlining_list->length(); i++) {
4000       tty->print("%s", _print_inlining_list->adr_at(i)->ss()->as_string());
4001     }
4002   }
4003 }
4004 
4005 // Dump inlining replay data to the stream.
4006 // Don't change thread state and acquire any locks.
4007 void Compile::dump_inline_data(outputStream* out) {
4008   InlineTree* inl_tree = ilt();
4009   if (inl_tree != NULL) {
4010     out->print(" inline %d", inl_tree->count());
4011     inl_tree->dump_replay_data(out);
4012   }
4013 }
4014 
4015 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
4016   if (n1->Opcode() < n2->Opcode())      return -1;
4017   else if (n1->Opcode() > n2->Opcode()) return 1;
4018 
4019   assert(n1->req() == n2->req(), err_msg_res("can't compare %s nodes: n1->req() = %d, n2->req() = %d", NodeClassNames[n1->Opcode()], n1->req(), n2->req()));
4020   for (uint i = 1; i < n1->req(); i++) {
4021     if (n1->in(i) < n2->in(i))      return -1;
4022     else if (n1->in(i) > n2->in(i)) return 1;
4023   }
4024 
4025   return 0;
4026 }
4027 
4028 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
4029   Node* n1 = *n1p;
4030   Node* n2 = *n2p;
4031 
4032   return cmp_expensive_nodes(n1, n2);
4033 }
4034 
4035 void Compile::sort_expensive_nodes() {
4036   if (!expensive_nodes_sorted()) {
4037     _expensive_nodes->sort(cmp_expensive_nodes);
4038   }
4039 }
4040 
4041 bool Compile::expensive_nodes_sorted() const {
4042   for (int i = 1; i < _expensive_nodes->length(); i++) {
4043     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
4044       return false;
4045     }
4046   }
4047   return true;
4048 }
4049 
4050 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
4051   if (_expensive_nodes->length() == 0) {
4052     return false;
4053   }
4054 
4055   assert(OptimizeExpensiveOps, "optimization off?");
4056 
4057   // Take this opportunity to remove dead nodes from the list
4058   int j = 0;
4059   for (int i = 0; i < _expensive_nodes->length(); i++) {
4060     Node* n = _expensive_nodes->at(i);
4061     if (!n->is_unreachable(igvn)) {
4062       assert(n->is_expensive(), "should be expensive");
4063       _expensive_nodes->at_put(j, n);
4064       j++;
4065     }
4066   }
4067   _expensive_nodes->trunc_to(j);
4068 
4069   // Then sort the list so that similar nodes are next to each other
4070   // and check for at least two nodes of identical kind with same data
4071   // inputs.
4072   sort_expensive_nodes();
4073 
4074   for (int i = 0; i < _expensive_nodes->length()-1; i++) {
4075     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
4076       return true;
4077     }
4078   }
4079 
4080   return false;
4081 }
4082 
4083 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
4084   if (_expensive_nodes->length() == 0) {
4085     return;
4086   }
4087 
4088   assert(OptimizeExpensiveOps, "optimization off?");
4089 
4090   // Sort to bring similar nodes next to each other and clear the
4091   // control input of nodes for which there's only a single copy.
4092   sort_expensive_nodes();
4093 
4094   int j = 0;
4095   int identical = 0;
4096   int i = 0;
4097   for (; i < _expensive_nodes->length()-1; i++) {
4098     assert(j <= i, "can't write beyond current index");
4099     if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
4100       identical++;
4101       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4102       continue;
4103     }
4104     if (identical > 0) {
4105       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4106       identical = 0;
4107     } else {
4108       Node* n = _expensive_nodes->at(i);
4109       igvn.hash_delete(n);
4110       n->set_req(0, NULL);
4111       igvn.hash_insert(n);
4112     }
4113   }
4114   if (identical > 0) {
4115     _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4116   } else if (_expensive_nodes->length() >= 1) {
4117     Node* n = _expensive_nodes->at(i);
4118     igvn.hash_delete(n);
4119     n->set_req(0, NULL);
4120     igvn.hash_insert(n);
4121   }
4122   _expensive_nodes->trunc_to(j);
4123 }
4124 
4125 void Compile::add_expensive_node(Node * n) {
4126   assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
4127   assert(n->is_expensive(), "expensive nodes with non-null control here only");
4128   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
4129   if (OptimizeExpensiveOps) {
4130     _expensive_nodes->append(n);
4131   } else {
4132     // Clear control input and let IGVN optimize expensive nodes if
4133     // OptimizeExpensiveOps is off.
4134     n->set_req(0, NULL);
4135   }
4136 }
4137 
4138 /**
4139  * Remove the speculative part of types and clean up the graph
4140  */
4141 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
4142   if (UseTypeSpeculation) {
4143     Unique_Node_List worklist;
4144     worklist.push(root());
4145     int modified = 0;
4146     // Go over all type nodes that carry a speculative type, drop the
4147     // speculative part of the type and enqueue the node for an igvn
4148     // which may optimize it out.
4149     for (uint next = 0; next < worklist.size(); ++next) {
4150       Node *n  = worklist.at(next);
4151       if (n->is_Type()) {
4152         TypeNode* tn = n->as_Type();
4153         const Type* t = tn->type();
4154         const Type* t_no_spec = t->remove_speculative();
4155         if (t_no_spec != t) {
4156           bool in_hash = igvn.hash_delete(n);
4157           assert(in_hash || n->hash() == Node::NO_HASH, "node should be in igvn hash table");
4158           tn->set_type(t_no_spec);
4159           igvn.hash_insert(n);
4160           igvn._worklist.push(n); // give it a chance to go away
4161           modified++;
4162         }
4163       }
4164       uint max = n->len();
4165       for( uint i = 0; i < max; ++i ) {
4166         Node *m = n->in(i);
4167         if (not_a_node(m))  continue;
4168         worklist.push(m);
4169       }
4170     }
4171     // Drop the speculative part of all types in the igvn's type table
4172     igvn.remove_speculative_types();
4173     if (modified > 0) {
4174       igvn.optimize();
4175     }
4176 #ifdef ASSERT
4177     // Verify that after the IGVN is over no speculative type has resurfaced
4178     worklist.clear();
4179     worklist.push(root());
4180     for (uint next = 0; next < worklist.size(); ++next) {
4181       Node *n  = worklist.at(next);
4182       const Type* t = igvn.type_or_null(n);
4183       assert((t == NULL) || (t == t->remove_speculative()), "no more speculative types");
4184       if (n->is_Type()) {
4185         t = n->as_Type()->type();
4186         assert(t == t->remove_speculative(), "no more speculative types");
4187       }
4188       uint max = n->len();
4189       for( uint i = 0; i < max; ++i ) {
4190         Node *m = n->in(i);
4191         if (not_a_node(m))  continue;
4192         worklist.push(m);
4193       }
4194     }
4195     igvn.check_no_speculative_types();
4196 #endif
4197   }
4198 }
4199 
4200 // Convert integer value to a narrowed long type dependent on ctrl (for example, a range check)
4201 Node* Compile::constrained_convI2L(PhaseGVN* phase, Node* value, const TypeInt* itype, Node* ctrl) {
4202   if (ctrl != NULL) {
4203     // Express control dependency by a CastII node with a narrow type.
4204     value = new (phase->C) CastIINode(value, itype, false, true /* range check dependency */);
4205     // Make the CastII node dependent on the control input to prevent the narrowed ConvI2L
4206     // node from floating above the range check during loop optimizations. Otherwise, the
4207     // ConvI2L node may be eliminated independently of the range check, causing the data path
4208     // to become TOP while the control path is still there (although it's unreachable).
4209     value->set_req(0, ctrl);
4210     // Save CastII node to remove it after loop optimizations.
4211     phase->C->add_range_check_cast(value);
4212     value = phase->transform(value);
4213   }
4214   const TypeLong* ltype = TypeLong::make(itype->_lo, itype->_hi, itype->_widen);
4215   return phase->transform(new (phase->C) ConvI2LNode(value, ltype));
4216 }
4217 
4218 // Auxiliary method to support randomized stressing/fuzzing.
4219 //
4220 // This method can be called the arbitrary number of times, with current count
4221 // as the argument. The logic allows selecting a single candidate from the
4222 // running list of candidates as follows:
4223 //    int count = 0;
4224 //    Cand* selected = null;
4225 //    while(cand = cand->next()) {
4226 //      if (randomized_select(++count)) {
4227 //        selected = cand;
4228 //      }
4229 //    }
4230 //
4231 // Including count equalizes the chances any candidate is "selected".
4232 // This is useful when we don't have the complete list of candidates to choose
4233 // from uniformly. In this case, we need to adjust the randomicity of the
4234 // selection, or else we will end up biasing the selection towards the latter
4235 // candidates.
4236 //
4237 // Quick back-envelope calculation shows that for the list of n candidates
4238 // the equal probability for the candidate to persist as "best" can be
4239 // achieved by replacing it with "next" k-th candidate with the probability
4240 // of 1/k. It can be easily shown that by the end of the run, the
4241 // probability for any candidate is converged to 1/n, thus giving the
4242 // uniform distribution among all the candidates.
4243 //
4244 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
4245 #define RANDOMIZED_DOMAIN_POW 29
4246 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
4247 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
4248 bool Compile::randomized_select(int count) {
4249   assert(count > 0, "only positive");
4250   return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);
4251 }
4252 
4253 void Compile::shenandoah_eliminate_g1_wb_pre(Node* call, PhaseIterGVN* igvn) {
4254   assert(UseShenandoahGC && call->is_g1_wb_pre_call(), "");
4255   Node* c = call->as_Call()->proj_out(TypeFunc::Control);
4256   c = c->unique_ctrl_out();
4257   assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?");
4258   c = c->unique_ctrl_out();
4259   assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?");
4260   Node* iff = c->in(1)->is_IfProj() ? c->in(1)->in(0) : c->in(2)->in(0);
4261   assert(iff->is_If(), "expect test");
4262   if (!iff->is_shenandoah_marking_if(igvn)) {
4263     c = c->unique_ctrl_out();
4264     assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?");
4265     iff = c->in(1)->is_IfProj() ? c->in(1)->in(0) : c->in(2)->in(0);
4266     assert(iff->is_shenandoah_marking_if(igvn), "expect marking test");
4267   }
4268   Node* cmpx = iff->in(1)->in(1);
4269   igvn->replace_node(cmpx, igvn->makecon(TypeInt::CC_EQ));
4270   igvn->rehash_node_delayed(call);
4271   call->del_req(call->req()-1);
4272 }