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/compileBroker.hpp"
  33 #include "compiler/compileLog.hpp"
  34 #include "compiler/disassembler.hpp"
  35 #include "compiler/oopMap.hpp"
  36 #include "gc/shared/barrierSet.hpp"
  37 #include "gc/shared/c2/barrierSetC2.hpp"
  38 #include "memory/resourceArea.hpp"
  39 #include "opto/addnode.hpp"
  40 #include "opto/block.hpp"
  41 #include "opto/c2compiler.hpp"
  42 #include "opto/callGenerator.hpp"
  43 #include "opto/callnode.hpp"
  44 #include "opto/castnode.hpp"
  45 #include "opto/cfgnode.hpp"
  46 #include "opto/chaitin.hpp"
  47 #include "opto/compile.hpp"
  48 #include "opto/connode.hpp"
  49 #include "opto/convertnode.hpp"
  50 #include "opto/divnode.hpp"
  51 #include "opto/escape.hpp"
  52 #include "opto/idealGraphPrinter.hpp"
  53 #include "opto/loopnode.hpp"
  54 #include "opto/machnode.hpp"
  55 #include "opto/macro.hpp"
  56 #include "opto/matcher.hpp"
  57 #include "opto/mathexactnode.hpp"
  58 #include "opto/memnode.hpp"
  59 #include "opto/mulnode.hpp"
  60 #include "opto/narrowptrnode.hpp"
  61 #include "opto/node.hpp"
  62 #include "opto/opcodes.hpp"
  63 #include "opto/output.hpp"
  64 #include "opto/parse.hpp"
  65 #include "opto/phaseX.hpp"
  66 #include "opto/rootnode.hpp"
  67 #include "opto/runtime.hpp"
  68 #include "opto/stringopts.hpp"
  69 #include "opto/type.hpp"
  70 #include "opto/vectornode.hpp"
  71 #include "runtime/arguments.hpp"
  72 #include "runtime/sharedRuntime.hpp"
  73 #include "runtime/signature.hpp"
  74 #include "runtime/stubRoutines.hpp"
  75 #include "runtime/timer.hpp"
  76 #include "utilities/align.hpp"
  77 #include "utilities/copy.hpp"
  78 #include "utilities/macros.hpp"
  79 #if INCLUDE_G1GC
  80 #include "gc/g1/g1ThreadLocalData.hpp"
  81 #endif // INCLUDE_G1GC
  82 #if INCLUDE_ZGC
  83 #include "gc/z/c2/zBarrierSetC2.hpp"
  84 #endif
  85 #if INCLUDE_SHENANDOAHGC
  86 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
  87 #endif
  88 
  89 
  90 // -------------------- Compile::mach_constant_base_node -----------------------
  91 // Constant table base node singleton.
  92 MachConstantBaseNode* Compile::mach_constant_base_node() {
  93   if (_mach_constant_base_node == NULL) {
  94     _mach_constant_base_node = new MachConstantBaseNode();
  95     _mach_constant_base_node->add_req(C->root());
  96   }
  97   return _mach_constant_base_node;
  98 }
  99 
 100 
 101 /// Support for intrinsics.
 102 
 103 // Return the index at which m must be inserted (or already exists).
 104 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
 105 class IntrinsicDescPair {
 106  private:
 107   ciMethod* _m;
 108   bool _is_virtual;
 109  public:
 110   IntrinsicDescPair(ciMethod* m, bool is_virtual) : _m(m), _is_virtual(is_virtual) {}
 111   static int compare(IntrinsicDescPair* const& key, CallGenerator* const& elt) {
 112     ciMethod* m= elt->method();
 113     ciMethod* key_m = key->_m;
 114     if (key_m < m)      return -1;
 115     else if (key_m > m) return 1;
 116     else {
 117       bool is_virtual = elt->is_virtual();
 118       bool key_virtual = key->_is_virtual;
 119       if (key_virtual < is_virtual)      return -1;
 120       else if (key_virtual > is_virtual) return 1;
 121       else                               return 0;
 122     }
 123   }
 124 };
 125 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual, bool& found) {
 126 #ifdef ASSERT
 127   for (int i = 1; i < _intrinsics->length(); i++) {
 128     CallGenerator* cg1 = _intrinsics->at(i-1);
 129     CallGenerator* cg2 = _intrinsics->at(i);
 130     assert(cg1->method() != cg2->method()
 131            ? cg1->method()     < cg2->method()
 132            : cg1->is_virtual() < cg2->is_virtual(),
 133            "compiler intrinsics list must stay sorted");
 134   }
 135 #endif
 136   IntrinsicDescPair pair(m, is_virtual);
 137   return _intrinsics->find_sorted<IntrinsicDescPair*, IntrinsicDescPair::compare>(&pair, found);
 138 }
 139 
 140 void Compile::register_intrinsic(CallGenerator* cg) {
 141   if (_intrinsics == NULL) {
 142     _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
 143   }
 144   int len = _intrinsics->length();
 145   bool found = false;
 146   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual(), found);
 147   assert(!found, "registering twice");
 148   _intrinsics->insert_before(index, cg);
 149   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
 150 }
 151 
 152 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
 153   assert(m->is_loaded(), "don't try this on unloaded methods");
 154   if (_intrinsics != NULL) {
 155     bool found = false;
 156     int index = intrinsic_insertion_index(m, is_virtual, found);
 157      if (found) {
 158       return _intrinsics->at(index);
 159     }
 160   }
 161   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
 162   if (m->intrinsic_id() != vmIntrinsics::_none &&
 163       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
 164     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
 165     if (cg != NULL) {
 166       // Save it for next time:
 167       register_intrinsic(cg);
 168       return cg;
 169     } else {
 170       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
 171     }
 172   }
 173   return NULL;
 174 }
 175 
 176 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
 177 // in library_call.cpp.
 178 
 179 
 180 #ifndef PRODUCT
 181 // statistics gathering...
 182 
 183 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
 184 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
 185 
 186 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
 187   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
 188   int oflags = _intrinsic_hist_flags[id];
 189   assert(flags != 0, "what happened?");
 190   if (is_virtual) {
 191     flags |= _intrinsic_virtual;
 192   }
 193   bool changed = (flags != oflags);
 194   if ((flags & _intrinsic_worked) != 0) {
 195     juint count = (_intrinsic_hist_count[id] += 1);
 196     if (count == 1) {
 197       changed = true;           // first time
 198     }
 199     // increment the overall count also:
 200     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
 201   }
 202   if (changed) {
 203     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
 204       // Something changed about the intrinsic's virtuality.
 205       if ((flags & _intrinsic_virtual) != 0) {
 206         // This is the first use of this intrinsic as a virtual call.
 207         if (oflags != 0) {
 208           // We already saw it as a non-virtual, so note both cases.
 209           flags |= _intrinsic_both;
 210         }
 211       } else if ((oflags & _intrinsic_both) == 0) {
 212         // This is the first use of this intrinsic as a non-virtual
 213         flags |= _intrinsic_both;
 214       }
 215     }
 216     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
 217   }
 218   // update the overall flags also:
 219   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
 220   return changed;
 221 }
 222 
 223 static char* format_flags(int flags, char* buf) {
 224   buf[0] = 0;
 225   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
 226   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
 227   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
 228   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
 229   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
 230   if (buf[0] == 0)  strcat(buf, ",");
 231   assert(buf[0] == ',', "must be");
 232   return &buf[1];
 233 }
 234 
 235 void Compile::print_intrinsic_statistics() {
 236   char flagsbuf[100];
 237   ttyLocker ttyl;
 238   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
 239   tty->print_cr("Compiler intrinsic usage:");
 240   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
 241   if (total == 0)  total = 1;  // avoid div0 in case of no successes
 242   #define PRINT_STAT_LINE(name, c, f) \
 243     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
 244   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
 245     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
 246     int   flags = _intrinsic_hist_flags[id];
 247     juint count = _intrinsic_hist_count[id];
 248     if ((flags | count) != 0) {
 249       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
 250     }
 251   }
 252   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
 253   if (xtty != NULL)  xtty->tail("statistics");
 254 }
 255 
 256 void Compile::print_statistics() {
 257   { ttyLocker ttyl;
 258     if (xtty != NULL)  xtty->head("statistics type='opto'");
 259     Parse::print_statistics();
 260     PhaseCCP::print_statistics();
 261     PhaseRegAlloc::print_statistics();
 262     Scheduling::print_statistics();
 263     PhasePeephole::print_statistics();
 264     PhaseIdealLoop::print_statistics();
 265     if (xtty != NULL)  xtty->tail("statistics");
 266   }
 267   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
 268     // put this under its own <statistics> element.
 269     print_intrinsic_statistics();
 270   }
 271 }
 272 #endif //PRODUCT
 273 
 274 // Support for bundling info
 275 Bundle* Compile::node_bundling(const Node *n) {
 276   assert(valid_bundle_info(n), "oob");
 277   return &_node_bundling_base[n->_idx];
 278 }
 279 
 280 bool Compile::valid_bundle_info(const Node *n) {
 281   return (_node_bundling_limit > n->_idx);
 282 }
 283 
 284 
 285 void Compile::gvn_replace_by(Node* n, Node* nn) {
 286   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
 287     Node* use = n->last_out(i);
 288     bool is_in_table = initial_gvn()->hash_delete(use);
 289     uint uses_found = 0;
 290     for (uint j = 0; j < use->len(); j++) {
 291       if (use->in(j) == n) {
 292         if (j < use->req())
 293           use->set_req(j, nn);
 294         else
 295           use->set_prec(j, nn);
 296         uses_found++;
 297       }
 298     }
 299     if (is_in_table) {
 300       // reinsert into table
 301       initial_gvn()->hash_find_insert(use);
 302     }
 303     record_for_igvn(use);
 304     i -= uses_found;    // we deleted 1 or more copies of this edge
 305   }
 306 }
 307 
 308 
 309 static inline bool not_a_node(const Node* n) {
 310   if (n == NULL)                   return true;
 311   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
 312   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
 313   return false;
 314 }
 315 
 316 // Identify all nodes that are reachable from below, useful.
 317 // Use breadth-first pass that records state in a Unique_Node_List,
 318 // recursive traversal is slower.
 319 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
 320   int estimated_worklist_size = live_nodes();
 321   useful.map( estimated_worklist_size, NULL );  // preallocate space
 322 
 323   // Initialize worklist
 324   if (root() != NULL)     { useful.push(root()); }
 325   // If 'top' is cached, declare it useful to preserve cached node
 326   if( cached_top_node() ) { useful.push(cached_top_node()); }
 327 
 328   // Push all useful nodes onto the list, breadthfirst
 329   for( uint next = 0; next < useful.size(); ++next ) {
 330     assert( next < unique(), "Unique useful nodes < total nodes");
 331     Node *n  = useful.at(next);
 332     uint max = n->len();
 333     for( uint i = 0; i < max; ++i ) {
 334       Node *m = n->in(i);
 335       if (not_a_node(m))  continue;
 336       useful.push(m);
 337     }
 338   }
 339 }
 340 
 341 // Update dead_node_list with any missing dead nodes using useful
 342 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
 343 void Compile::update_dead_node_list(Unique_Node_List &useful) {
 344   uint max_idx = unique();
 345   VectorSet& useful_node_set = useful.member_set();
 346 
 347   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
 348     // If node with index node_idx is not in useful set,
 349     // mark it as dead in dead node list.
 350     if (! useful_node_set.test(node_idx) ) {
 351       record_dead_node(node_idx);
 352     }
 353   }
 354 }
 355 
 356 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
 357   int shift = 0;
 358   for (int i = 0; i < inlines->length(); i++) {
 359     CallGenerator* cg = inlines->at(i);
 360     CallNode* call = cg->call_node();
 361     if (shift > 0) {
 362       inlines->at_put(i-shift, cg);
 363     }
 364     if (!useful.member(call)) {
 365       shift++;
 366     }
 367   }
 368   inlines->trunc_to(inlines->length()-shift);
 369 }
 370 
 371 // Disconnect all useless nodes by disconnecting those at the boundary.
 372 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
 373   uint next = 0;
 374   while (next < useful.size()) {
 375     Node *n = useful.at(next++);
 376     if (n->is_SafePoint()) {
 377       // We're done with a parsing phase. Replaced nodes are not valid
 378       // beyond that point.
 379       n->as_SafePoint()->delete_replaced_nodes();
 380     }
 381     // Use raw traversal of out edges since this code removes out edges
 382     int max = n->outcnt();
 383     for (int j = 0; j < max; ++j) {
 384       Node* child = n->raw_out(j);
 385       if (! useful.member(child)) {
 386         assert(!child->is_top() || child != top(),
 387                "If top is cached in Compile object it is in useful list");
 388         // Only need to remove this out-edge to the useless node
 389         n->raw_del_out(j);
 390         --j;
 391         --max;
 392       }
 393     }
 394     if (n->outcnt() == 1 && n->has_special_unique_user()) {
 395       record_for_igvn(n->unique_out());
 396     }
 397   }
 398   // Remove useless macro and predicate opaq nodes
 399   for (int i = C->macro_count()-1; i >= 0; i--) {
 400     Node* n = C->macro_node(i);
 401     if (!useful.member(n)) {
 402       remove_macro_node(n);
 403     }
 404   }
 405   // Remove useless CastII nodes with range check dependency
 406   for (int i = range_check_cast_count() - 1; i >= 0; i--) {
 407     Node* cast = range_check_cast_node(i);
 408     if (!useful.member(cast)) {
 409       remove_range_check_cast(cast);
 410     }
 411   }
 412   // Remove useless expensive nodes
 413   for (int i = C->expensive_count()-1; i >= 0; i--) {
 414     Node* n = C->expensive_node(i);
 415     if (!useful.member(n)) {
 416       remove_expensive_node(n);
 417     }
 418   }
 419   // Remove useless Opaque4 nodes
 420   for (int i = opaque4_count() - 1; i >= 0; i--) {
 421     Node* opaq = opaque4_node(i);
 422     if (!useful.member(opaq)) {
 423       remove_opaque4_node(opaq);
 424     }
 425   }
 426   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 427   bs->eliminate_useless_gc_barriers(useful);
 428   // clean up the late inline lists
 429   remove_useless_late_inlines(&_string_late_inlines, useful);
 430   remove_useless_late_inlines(&_boxing_late_inlines, useful);
 431   remove_useless_late_inlines(&_late_inlines, useful);
 432   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
 433 }
 434 
 435 //------------------------------frame_size_in_words-----------------------------
 436 // frame_slots in units of words
 437 int Compile::frame_size_in_words() const {
 438   // shift is 0 in LP32 and 1 in LP64
 439   const int shift = (LogBytesPerWord - LogBytesPerInt);
 440   int words = _frame_slots >> shift;
 441   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
 442   return words;
 443 }
 444 
 445 // To bang the stack of this compiled method we use the stack size
 446 // that the interpreter would need in case of a deoptimization. This
 447 // removes the need to bang the stack in the deoptimization blob which
 448 // in turn simplifies stack overflow handling.
 449 int Compile::bang_size_in_bytes() const {
 450   return MAX2(frame_size_in_bytes() + os::extra_bang_size_in_bytes(), _interpreter_frame_size);
 451 }
 452 
 453 // ============================================================================
 454 //------------------------------CompileWrapper---------------------------------
 455 class CompileWrapper : public StackObj {
 456   Compile *const _compile;
 457  public:
 458   CompileWrapper(Compile* compile);
 459 
 460   ~CompileWrapper();
 461 };
 462 
 463 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
 464   // the Compile* pointer is stored in the current ciEnv:
 465   ciEnv* env = compile->env();
 466   assert(env == ciEnv::current(), "must already be a ciEnv active");
 467   assert(env->compiler_data() == NULL, "compile already active?");
 468   env->set_compiler_data(compile);
 469   assert(compile == Compile::current(), "sanity");
 470 
 471   compile->set_type_dict(NULL);
 472   compile->set_clone_map(new Dict(cmpkey, hashkey, _compile->comp_arena()));
 473   compile->clone_map().set_clone_idx(0);
 474   compile->set_type_hwm(NULL);
 475   compile->set_type_last_size(0);
 476   compile->set_last_tf(NULL, NULL);
 477   compile->set_indexSet_arena(NULL);
 478   compile->set_indexSet_free_block_list(NULL);
 479   compile->init_type_arena();
 480   Type::Initialize(compile);
 481   _compile->set_scratch_buffer_blob(NULL);
 482   _compile->begin_method();
 483   _compile->clone_map().set_debug(_compile->has_method() && _compile->directive()->CloneMapDebugOption);
 484 }
 485 CompileWrapper::~CompileWrapper() {
 486   _compile->end_method();
 487   if (_compile->scratch_buffer_blob() != NULL)
 488     BufferBlob::free(_compile->scratch_buffer_blob());
 489   _compile->env()->set_compiler_data(NULL);
 490 }
 491 
 492 
 493 //----------------------------print_compile_messages---------------------------
 494 void Compile::print_compile_messages() {
 495 #ifndef PRODUCT
 496   // Check if recompiling
 497   if (_subsume_loads == false && PrintOpto) {
 498     // Recompiling without allowing machine instructions to subsume loads
 499     tty->print_cr("*********************************************************");
 500     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
 501     tty->print_cr("*********************************************************");
 502   }
 503   if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
 504     // Recompiling without escape analysis
 505     tty->print_cr("*********************************************************");
 506     tty->print_cr("** Bailout: Recompile without escape analysis          **");
 507     tty->print_cr("*********************************************************");
 508   }
 509   if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
 510     // Recompiling without boxing elimination
 511     tty->print_cr("*********************************************************");
 512     tty->print_cr("** Bailout: Recompile without boxing elimination       **");
 513     tty->print_cr("*********************************************************");
 514   }
 515   if (C->directive()->BreakAtCompileOption) {
 516     // Open the debugger when compiling this method.
 517     tty->print("### Breaking when compiling: ");
 518     method()->print_short_name();
 519     tty->cr();
 520     BREAKPOINT;
 521   }
 522 
 523   if( PrintOpto ) {
 524     if (is_osr_compilation()) {
 525       tty->print("[OSR]%3d", _compile_id);
 526     } else {
 527       tty->print("%3d", _compile_id);
 528     }
 529   }
 530 #endif
 531 }
 532 
 533 
 534 //-----------------------init_scratch_buffer_blob------------------------------
 535 // Construct a temporary BufferBlob and cache it for this compile.
 536 void Compile::init_scratch_buffer_blob(int const_size) {
 537   // If there is already a scratch buffer blob allocated and the
 538   // constant section is big enough, use it.  Otherwise free the
 539   // current and allocate a new one.
 540   BufferBlob* blob = scratch_buffer_blob();
 541   if ((blob != NULL) && (const_size <= _scratch_const_size)) {
 542     // Use the current blob.
 543   } else {
 544     if (blob != NULL) {
 545       BufferBlob::free(blob);
 546     }
 547 
 548     ResourceMark rm;
 549     _scratch_const_size = const_size;
 550     int size = C2Compiler::initial_code_buffer_size(const_size);
 551     blob = BufferBlob::create("Compile::scratch_buffer", size);
 552     // Record the buffer blob for next time.
 553     set_scratch_buffer_blob(blob);
 554     // Have we run out of code space?
 555     if (scratch_buffer_blob() == NULL) {
 556       // Let CompilerBroker disable further compilations.
 557       record_failure("Not enough space for scratch buffer in CodeCache");
 558       return;
 559     }
 560   }
 561 
 562   // Initialize the relocation buffers
 563   relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
 564   set_scratch_locs_memory(locs_buf);
 565 }
 566 
 567 
 568 //-----------------------scratch_emit_size-------------------------------------
 569 // Helper function that computes size by emitting code
 570 uint Compile::scratch_emit_size(const Node* n) {
 571   // Start scratch_emit_size section.
 572   set_in_scratch_emit_size(true);
 573 
 574   // Emit into a trash buffer and count bytes emitted.
 575   // This is a pretty expensive way to compute a size,
 576   // but it works well enough if seldom used.
 577   // All common fixed-size instructions are given a size
 578   // method by the AD file.
 579   // Note that the scratch buffer blob and locs memory are
 580   // allocated at the beginning of the compile task, and
 581   // may be shared by several calls to scratch_emit_size.
 582   // The allocation of the scratch buffer blob is particularly
 583   // expensive, since it has to grab the code cache lock.
 584   BufferBlob* blob = this->scratch_buffer_blob();
 585   assert(blob != NULL, "Initialize BufferBlob at start");
 586   assert(blob->size() > MAX_inst_size, "sanity");
 587   relocInfo* locs_buf = scratch_locs_memory();
 588   address blob_begin = blob->content_begin();
 589   address blob_end   = (address)locs_buf;
 590   assert(blob->contains(blob_end), "sanity");
 591   CodeBuffer buf(blob_begin, blob_end - blob_begin);
 592   buf.initialize_consts_size(_scratch_const_size);
 593   buf.initialize_stubs_size(MAX_stubs_size);
 594   assert(locs_buf != NULL, "sanity");
 595   int lsize = MAX_locs_size / 3;
 596   buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
 597   buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
 598   buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
 599   // Mark as scratch buffer.
 600   buf.consts()->set_scratch_emit();
 601   buf.insts()->set_scratch_emit();
 602   buf.stubs()->set_scratch_emit();
 603 
 604   // Do the emission.
 605 
 606   Label fakeL; // Fake label for branch instructions.
 607   Label*   saveL = NULL;
 608   uint save_bnum = 0;
 609   bool is_branch = n->is_MachBranch();
 610   if (is_branch) {
 611     MacroAssembler masm(&buf);
 612     masm.bind(fakeL);
 613     n->as_MachBranch()->save_label(&saveL, &save_bnum);
 614     n->as_MachBranch()->label_set(&fakeL, 0);
 615   }
 616   n->emit(buf, this->regalloc());
 617 
 618   // Emitting into the scratch buffer should not fail
 619   assert (!failing(), "Must not have pending failure. Reason is: %s", failure_reason());
 620 
 621   if (is_branch) // Restore label.
 622     n->as_MachBranch()->label_set(saveL, save_bnum);
 623 
 624   // End scratch_emit_size section.
 625   set_in_scratch_emit_size(false);
 626 
 627   return buf.insts_size();
 628 }
 629 
 630 
 631 // ============================================================================
 632 //------------------------------Compile standard-------------------------------
 633 debug_only( int Compile::_debug_idx = 100000; )
 634 
 635 // Compile a method.  entry_bci is -1 for normal compilations and indicates
 636 // the continuation bci for on stack replacement.
 637 
 638 
 639 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
 640                   bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing, DirectiveSet* directive)
 641                 : Phase(Compiler),
 642                   _env(ci_env),
 643                   _directive(directive),
 644                   _log(ci_env->log()),
 645                   _compile_id(ci_env->compile_id()),
 646                   _save_argument_registers(false),
 647                   _stub_name(NULL),
 648                   _stub_function(NULL),
 649                   _stub_entry_point(NULL),
 650                   _method(target),
 651                   _barrier_set_state(BarrierSet::barrier_set()->barrier_set_c2()->create_barrier_state(comp_arena())),
 652                   _entry_bci(osr_bci),
 653                   _initial_gvn(NULL),
 654                   _for_igvn(NULL),
 655                   _warm_calls(NULL),
 656                   _subsume_loads(subsume_loads),
 657                   _do_escape_analysis(do_escape_analysis),
 658                   _eliminate_boxing(eliminate_boxing),
 659                   _failure_reason(NULL),
 660                   _code_buffer("Compile::Fill_buffer"),
 661                   _orig_pc_slot(0),
 662                   _orig_pc_slot_offset_in_bytes(0),
 663                   _has_method_handle_invokes(false),
 664                   _mach_constant_base_node(NULL),
 665                   _node_bundling_limit(0),
 666                   _node_bundling_base(NULL),
 667                   _java_calls(0),
 668                   _inner_loops(0),
 669                   _scratch_const_size(-1),
 670                   _in_scratch_emit_size(false),
 671                   _dead_node_list(comp_arena()),
 672                   _dead_node_count(0),
 673 #ifndef PRODUCT
 674                   _trace_opto_output(directive->TraceOptoOutputOption),
 675                   _in_dump_cnt(0),
 676                   _printer(IdealGraphPrinter::printer()),
 677 #endif
 678                   _congraph(NULL),
 679                   _comp_arena(mtCompiler),
 680                   _node_arena(mtCompiler),
 681                   _old_arena(mtCompiler),
 682                   _Compile_types(mtCompiler),
 683                   _replay_inline_data(NULL),
 684                   _late_inlines(comp_arena(), 2, 0, NULL),
 685                   _string_late_inlines(comp_arena(), 2, 0, NULL),
 686                   _boxing_late_inlines(comp_arena(), 2, 0, NULL),
 687                   _late_inlines_pos(0),
 688                   _number_of_mh_late_inlines(0),
 689                   _inlining_progress(false),
 690                   _inlining_incrementally(false),
 691                   _print_inlining_list(NULL),
 692                   _print_inlining_stream(NULL),
 693                   _print_inlining_idx(0),
 694                   _print_inlining_output(NULL),
 695                   _interpreter_frame_size(0),
 696                   _max_node_limit(MaxNodeLimit),
 697                   _has_reserved_stack_access(target->has_reserved_stack_access()) {
 698   C = this;
 699 #ifndef PRODUCT
 700   if (_printer != NULL) {
 701     _printer->set_compile(this);
 702   }
 703 #endif
 704   CompileWrapper cw(this);
 705 
 706   if (CITimeVerbose) {
 707     tty->print(" ");
 708     target->holder()->name()->print();
 709     tty->print(".");
 710     target->print_short_name();
 711     tty->print("  ");
 712   }
 713   TraceTime t1("Total compilation time", &_t_totalCompilation, CITime, CITimeVerbose);
 714   TraceTime t2(NULL, &_t_methodCompilation, CITime, false);
 715 
 716 #ifndef PRODUCT
 717   bool print_opto_assembly = directive->PrintOptoAssemblyOption;
 718   if (!print_opto_assembly) {
 719     bool print_assembly = directive->PrintAssemblyOption;
 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 (directive->ReplayInlineOption) {
 729     _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
 730   }
 731 #endif
 732   set_print_inlining(directive->PrintInliningOption || PrintOptoInlining);
 733   set_print_intrinsics(directive->PrintIntrinsicsOption);
 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   print_inlining_init();
 765   { // Scope for timing the parser
 766     TracePhase tp("parse", &timers[_t_parser]);
 767 
 768     // Put top into the hash table ASAP.
 769     initial_gvn()->transform_no_reclaim(top());
 770 
 771     // Set up tf(), start(), and find a CallGenerator.
 772     CallGenerator* cg = NULL;
 773     if (is_osr_compilation()) {
 774       const TypeTuple *domain = StartOSRNode::osr_domain();
 775       const TypeTuple *range = TypeTuple::make_range(method()->signature());
 776       init_tf(TypeFunc::make(domain, range));
 777       StartNode* s = new StartOSRNode(root(), domain);
 778       initial_gvn()->set_type_bottom(s);
 779       init_start(s);
 780       cg = CallGenerator::for_osr(method(), entry_bci());
 781     } else {
 782       // Normal case.
 783       init_tf(TypeFunc::make(method()));
 784       StartNode* s = new StartNode(root(), tf()->domain());
 785       initial_gvn()->set_type_bottom(s);
 786       init_start(s);
 787       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get) {
 788         // With java.lang.ref.reference.get() we must go through the
 789         // intrinsic - even when get() is the root
 790         // method of the compile - so that, if necessary, the value in
 791         // the referent field of the reference object gets recorded by
 792         // the pre-barrier code.
 793         cg = find_intrinsic(method(), false);
 794       }
 795       if (cg == NULL) {
 796         float past_uses = method()->interpreter_invocation_count();
 797         float expected_uses = past_uses;
 798         cg = CallGenerator::for_inline(method(), expected_uses);
 799       }
 800     }
 801     if (failing())  return;
 802     if (cg == NULL) {
 803       record_method_not_compilable("cannot parse method");
 804       return;
 805     }
 806     JVMState* jvms = build_start_state(start(), tf());
 807     if ((jvms = cg->generate(jvms)) == NULL) {
 808       if (!failure_reason_is(C2Compiler::retry_class_loading_during_parsing())) {
 809         record_method_not_compilable("method parse failed");
 810       }
 811       return;
 812     }
 813     GraphKit kit(jvms);
 814 
 815     if (!kit.stopped()) {
 816       // Accept return values, and transfer control we know not where.
 817       // This is done by a special, unique ReturnNode bound to root.
 818       return_values(kit.jvms());
 819     }
 820 
 821     if (kit.has_exceptions()) {
 822       // Any exceptions that escape from this call must be rethrown
 823       // to whatever caller is dynamically above us on the stack.
 824       // This is done by a special, unique RethrowNode bound to root.
 825       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
 826     }
 827 
 828     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
 829 
 830     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
 831       inline_string_calls(true);
 832     }
 833 
 834     if (failing())  return;
 835 
 836     print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
 837 
 838     // Remove clutter produced by parsing.
 839     if (!failing()) {
 840       ResourceMark rm;
 841       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
 842     }
 843   }
 844 
 845   // Note:  Large methods are capped off in do_one_bytecode().
 846   if (failing())  return;
 847 
 848   // After parsing, node notes are no longer automagic.
 849   // They must be propagated by register_new_node_with_optimizer(),
 850   // clone(), or the like.
 851   set_default_node_notes(NULL);
 852 
 853   for (;;) {
 854     int successes = Inline_Warm();
 855     if (failing())  return;
 856     if (successes == 0)  break;
 857   }
 858 
 859   // Drain the list.
 860   Finish_Warm();
 861 #ifndef PRODUCT
 862   if (_printer && _printer->should_print(1)) {
 863     _printer->print_inlining();
 864   }
 865 #endif
 866 
 867   if (failing())  return;
 868   NOT_PRODUCT( verify_graph_edges(); )
 869 
 870   // Now optimize
 871   Optimize();
 872   if (failing())  return;
 873   NOT_PRODUCT( verify_graph_edges(); )
 874 
 875 #ifndef PRODUCT
 876   if (PrintIdeal) {
 877     ttyLocker ttyl;  // keep the following output all in one block
 878     // This output goes directly to the tty, not the compiler log.
 879     // To enable tools to match it up with the compilation activity,
 880     // be sure to tag this tty output with the compile ID.
 881     if (xtty != NULL) {
 882       xtty->head("ideal compile_id='%d'%s", compile_id(),
 883                  is_osr_compilation()    ? " compile_kind='osr'" :
 884                  "");
 885     }
 886     root()->dump(9999);
 887     if (xtty != NULL) {
 888       xtty->tail("ideal");
 889     }
 890   }
 891 #endif
 892 
 893   NOT_PRODUCT( verify_barriers(); )
 894 
 895   // Dump compilation data to replay it.
 896   if (directive->DumpReplayOption) {
 897     env()->dump_replay_data(_compile_id);
 898   }
 899   if (directive->DumpInlineOption && (ilt() != NULL)) {
 900     env()->dump_inline_data(_compile_id);
 901   }
 902 
 903   // Now that we know the size of all the monitors we can add a fixed slot
 904   // for the original deopt pc.
 905 
 906   _orig_pc_slot =  fixed_slots();
 907   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
 908   set_fixed_slots(next_slot);
 909 
 910   // Compute when to use implicit null checks. Used by matching trap based
 911   // nodes and NullCheck optimization.
 912   set_allowed_deopt_reasons();
 913 
 914   // Now generate code
 915   Code_Gen();
 916   if (failing())  return;
 917 
 918   // Check if we want to skip execution of all compiled code.
 919   {
 920 #ifndef PRODUCT
 921     if (OptoNoExecute) {
 922       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
 923       return;
 924     }
 925 #endif
 926     TracePhase tp("install_code", &timers[_t_registerMethod]);
 927 
 928     if (is_osr_compilation()) {
 929       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
 930       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
 931     } else {
 932       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
 933       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
 934     }
 935 
 936     env()->register_method(_method, _entry_bci,
 937                            &_code_offsets,
 938                            _orig_pc_slot_offset_in_bytes,
 939                            code_buffer(),
 940                            frame_size_in_words(), _oop_map_set,
 941                            &_handler_table, &_inc_table,
 942                            compiler,
 943                            has_unsafe_access(),
 944                            SharedRuntime::is_wide_vector(max_vector_size()),
 945                            rtm_state()
 946                            );
 947 
 948     if (log() != NULL) // Print code cache state into compiler log
 949       log()->code_cache_state();
 950   }
 951 }
 952 
 953 //------------------------------Compile----------------------------------------
 954 // Compile a runtime stub
 955 Compile::Compile( ciEnv* ci_env,
 956                   TypeFunc_generator generator,
 957                   address stub_function,
 958                   const char *stub_name,
 959                   int is_fancy_jump,
 960                   bool pass_tls,
 961                   bool save_arg_registers,
 962                   bool return_pc,
 963                   DirectiveSet* directive)
 964   : Phase(Compiler),
 965     _env(ci_env),
 966     _directive(directive),
 967     _log(ci_env->log()),
 968     _compile_id(0),
 969     _save_argument_registers(save_arg_registers),
 970     _method(NULL),
 971     _stub_name(stub_name),
 972     _stub_function(stub_function),
 973     _stub_entry_point(NULL),
 974     _entry_bci(InvocationEntryBci),
 975     _initial_gvn(NULL),
 976     _for_igvn(NULL),
 977     _warm_calls(NULL),
 978     _orig_pc_slot(0),
 979     _orig_pc_slot_offset_in_bytes(0),
 980     _subsume_loads(true),
 981     _do_escape_analysis(false),
 982     _eliminate_boxing(false),
 983     _failure_reason(NULL),
 984     _code_buffer("Compile::Fill_buffer"),
 985     _has_method_handle_invokes(false),
 986     _mach_constant_base_node(NULL),
 987     _node_bundling_limit(0),
 988     _node_bundling_base(NULL),
 989     _java_calls(0),
 990     _inner_loops(0),
 991 #ifndef PRODUCT
 992     _trace_opto_output(directive->TraceOptoOutputOption),
 993     _in_dump_cnt(0),
 994     _printer(NULL),
 995 #endif
 996     _comp_arena(mtCompiler),
 997     _node_arena(mtCompiler),
 998     _old_arena(mtCompiler),
 999     _Compile_types(mtCompiler),
1000     _dead_node_list(comp_arena()),
1001     _dead_node_count(0),
1002     _congraph(NULL),
1003     _replay_inline_data(NULL),
1004     _number_of_mh_late_inlines(0),
1005     _inlining_progress(false),
1006     _inlining_incrementally(false),
1007     _print_inlining_list(NULL),
1008     _print_inlining_stream(NULL),
1009     _print_inlining_idx(0),
1010     _print_inlining_output(NULL),
1011     _allowed_reasons(0),
1012     _interpreter_frame_size(0),
1013     _max_node_limit(MaxNodeLimit),
1014     _has_reserved_stack_access(false) {
1015   C = this;
1016 
1017   TraceTime t1(NULL, &_t_totalCompilation, CITime, false);
1018   TraceTime t2(NULL, &_t_stubCompilation, CITime, false);
1019 
1020 #ifndef PRODUCT
1021   set_print_assembly(PrintFrameConverterAssembly);
1022   set_parsed_irreducible_loop(false);
1023 #endif
1024   set_has_irreducible_loop(false); // no loops
1025 
1026   CompileWrapper cw(this);
1027   Init(/*AliasLevel=*/ 0);
1028   init_tf((*generator)());
1029 
1030   {
1031     // The following is a dummy for the sake of GraphKit::gen_stub
1032     Unique_Node_List for_igvn(comp_arena());
1033     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
1034     PhaseGVN gvn(Thread::current()->resource_area(),255);
1035     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
1036     gvn.transform_no_reclaim(top());
1037 
1038     GraphKit kit;
1039     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
1040   }
1041 
1042   NOT_PRODUCT( verify_graph_edges(); )
1043   Code_Gen();
1044   if (failing())  return;
1045 
1046 
1047   // Entry point will be accessed using compile->stub_entry_point();
1048   if (code_buffer() == NULL) {
1049     Matcher::soft_match_failure();
1050   } else {
1051     if (PrintAssembly && (WizardMode || Verbose))
1052       tty->print_cr("### Stub::%s", stub_name);
1053 
1054     if (!failing()) {
1055       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
1056 
1057       // Make the NMethod
1058       // For now we mark the frame as never safe for profile stackwalking
1059       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
1060                                                       code_buffer(),
1061                                                       CodeOffsets::frame_never_safe,
1062                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
1063                                                       frame_size_in_words(),
1064                                                       _oop_map_set,
1065                                                       save_arg_registers);
1066       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
1067 
1068       _stub_entry_point = rs->entry_point();
1069     }
1070   }
1071 }
1072 
1073 //------------------------------Init-------------------------------------------
1074 // Prepare for a single compilation
1075 void Compile::Init(int aliaslevel) {
1076   _unique  = 0;
1077   _regalloc = NULL;
1078 
1079   _tf      = NULL;  // filled in later
1080   _top     = NULL;  // cached later
1081   _matcher = NULL;  // filled in later
1082   _cfg     = NULL;  // filled in later
1083 
1084   set_24_bit_selection_and_mode(Use24BitFP, false);
1085 
1086   _node_note_array = NULL;
1087   _default_node_notes = NULL;
1088   DEBUG_ONLY( _modified_nodes = NULL; ) // Used in Optimize()
1089 
1090   _immutable_memory = NULL; // filled in at first inquiry
1091 
1092   // Globally visible Nodes
1093   // First set TOP to NULL to give safe behavior during creation of RootNode
1094   set_cached_top_node(NULL);
1095   set_root(new RootNode());
1096   // Now that you have a Root to point to, create the real TOP
1097   set_cached_top_node( new ConNode(Type::TOP) );
1098   set_recent_alloc(NULL, NULL);
1099 
1100   // Create Debug Information Recorder to record scopes, oopmaps, etc.
1101   env()->set_oop_recorder(new OopRecorder(env()->arena()));
1102   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
1103   env()->set_dependencies(new Dependencies(env()));
1104 
1105   _fixed_slots = 0;
1106   set_has_split_ifs(false);
1107   set_has_loops(has_method() && method()->has_loops()); // first approximation
1108   set_has_stringbuilder(false);
1109   set_has_boxed_value(false);
1110   _trap_can_recompile = false;  // no traps emitted yet
1111   _major_progress = true; // start out assuming good things will happen
1112   set_has_unsafe_access(false);
1113   set_max_vector_size(0);
1114   set_clear_upper_avx(false);  //false as default for clear upper bits of ymm registers
1115   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
1116   set_decompile_count(0);
1117 
1118   set_do_freq_based_layout(_directive->BlockLayoutByFrequencyOption);
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 
1127   set_do_vector_loop(false);
1128 
1129   if (AllowVectorizeOnDemand) {
1130     if (has_method() && (_directive->VectorizeOption || _directive->VectorizeDebugOption)) {
1131       set_do_vector_loop(true);
1132       NOT_PRODUCT(if (do_vector_loop() && Verbose) {tty->print("Compile::Init: do vectorized loops (SIMD like) for method %s\n",  method()->name()->as_quoted_ascii());})
1133     } else if (has_method() && method()->name() != 0 &&
1134                method()->intrinsic_id() == vmIntrinsics::_forEachRemaining) {
1135       set_do_vector_loop(true);
1136     }
1137   }
1138   set_use_cmove(UseCMoveUnconditionally /* || do_vector_loop()*/); //TODO: consider do_vector_loop() mandate use_cmove unconditionally
1139   NOT_PRODUCT(if (use_cmove() && Verbose && has_method()) {tty->print("Compile::Init: use CMove without profitability tests for method %s\n",  method()->name()->as_quoted_ascii());})
1140 
1141   set_age_code(has_method() && method()->profile_aging());
1142   set_rtm_state(NoRTM); // No RTM lock eliding by default
1143   _max_node_limit = _directive->MaxNodeLimitOption;
1144 
1145 #if INCLUDE_RTM_OPT
1146   if (UseRTMLocking && has_method() && (method()->method_data_or_null() != NULL)) {
1147     int rtm_state = method()->method_data()->rtm_state();
1148     if (method_has_option("NoRTMLockEliding") || ((rtm_state & NoRTM) != 0)) {
1149       // Don't generate RTM lock eliding code.
1150       set_rtm_state(NoRTM);
1151     } else if (method_has_option("UseRTMLockEliding") || ((rtm_state & UseRTM) != 0) || !UseRTMDeopt) {
1152       // Generate RTM lock eliding code without abort ratio calculation code.
1153       set_rtm_state(UseRTM);
1154     } else if (UseRTMDeopt) {
1155       // Generate RTM lock eliding code and include abort ratio calculation
1156       // code if UseRTMDeopt is on.
1157       set_rtm_state(ProfileRTM);
1158     }
1159   }
1160 #endif
1161   if (debug_info()->recording_non_safepoints()) {
1162     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
1163                         (comp_arena(), 8, 0, NULL));
1164     set_default_node_notes(Node_Notes::make(this));
1165   }
1166 
1167   // // -- Initialize types before each compile --
1168   // // Update cached type information
1169   // if( _method && _method->constants() )
1170   //   Type::update_loaded_types(_method, _method->constants());
1171 
1172   // Init alias_type map.
1173   if (!_do_escape_analysis && aliaslevel == 3)
1174     aliaslevel = 2;  // No unique types without escape analysis
1175   _AliasLevel = aliaslevel;
1176   const int grow_ats = 16;
1177   _max_alias_types = grow_ats;
1178   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1179   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
1180   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1181   {
1182     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
1183   }
1184   // Initialize the first few types.
1185   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
1186   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1187   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1188   _num_alias_types = AliasIdxRaw+1;
1189   // Zero out the alias type cache.
1190   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1191   // A NULL adr_type hits in the cache right away.  Preload the right answer.
1192   probe_alias_cache(NULL)->_index = AliasIdxTop;
1193 
1194   _intrinsics = NULL;
1195   _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1196   _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1197   _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1198   _range_check_casts = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1199   _opaque4_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1200   register_library_intrinsics();
1201 }
1202 
1203 //---------------------------init_start----------------------------------------
1204 // Install the StartNode on this compile object.
1205 void Compile::init_start(StartNode* s) {
1206   if (failing())
1207     return; // already failing
1208   assert(s == start(), "");
1209 }
1210 
1211 /**
1212  * Return the 'StartNode'. We must not have a pending failure, since the ideal graph
1213  * can be in an inconsistent state, i.e., we can get segmentation faults when traversing
1214  * the ideal graph.
1215  */
1216 StartNode* Compile::start() const {
1217   assert (!failing(), "Must not have pending failure. Reason is: %s", failure_reason());
1218   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1219     Node* start = root()->fast_out(i);
1220     if (start->is_Start()) {
1221       return start->as_Start();
1222     }
1223   }
1224   fatal("Did not find Start node!");
1225   return NULL;
1226 }
1227 
1228 //-------------------------------immutable_memory-------------------------------------
1229 // Access immutable memory
1230 Node* Compile::immutable_memory() {
1231   if (_immutable_memory != NULL) {
1232     return _immutable_memory;
1233   }
1234   StartNode* s = start();
1235   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1236     Node *p = s->fast_out(i);
1237     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1238       _immutable_memory = p;
1239       return _immutable_memory;
1240     }
1241   }
1242   ShouldNotReachHere();
1243   return NULL;
1244 }
1245 
1246 //----------------------set_cached_top_node------------------------------------
1247 // Install the cached top node, and make sure Node::is_top works correctly.
1248 void Compile::set_cached_top_node(Node* tn) {
1249   if (tn != NULL)  verify_top(tn);
1250   Node* old_top = _top;
1251   _top = tn;
1252   // Calling Node::setup_is_top allows the nodes the chance to adjust
1253   // their _out arrays.
1254   if (_top != NULL)     _top->setup_is_top();
1255   if (old_top != NULL)  old_top->setup_is_top();
1256   assert(_top == NULL || top()->is_top(), "");
1257 }
1258 
1259 #ifdef ASSERT
1260 uint Compile::count_live_nodes_by_graph_walk() {
1261   Unique_Node_List useful(comp_arena());
1262   // Get useful node list by walking the graph.
1263   identify_useful_nodes(useful);
1264   return useful.size();
1265 }
1266 
1267 void Compile::print_missing_nodes() {
1268 
1269   // Return if CompileLog is NULL and PrintIdealNodeCount is false.
1270   if ((_log == NULL) && (! PrintIdealNodeCount)) {
1271     return;
1272   }
1273 
1274   // This is an expensive function. It is executed only when the user
1275   // specifies VerifyIdealNodeCount option or otherwise knows the
1276   // additional work that needs to be done to identify reachable nodes
1277   // by walking the flow graph and find the missing ones using
1278   // _dead_node_list.
1279 
1280   Unique_Node_List useful(comp_arena());
1281   // Get useful node list by walking the graph.
1282   identify_useful_nodes(useful);
1283 
1284   uint l_nodes = C->live_nodes();
1285   uint l_nodes_by_walk = useful.size();
1286 
1287   if (l_nodes != l_nodes_by_walk) {
1288     if (_log != NULL) {
1289       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
1290       _log->stamp();
1291       _log->end_head();
1292     }
1293     VectorSet& useful_member_set = useful.member_set();
1294     int last_idx = l_nodes_by_walk;
1295     for (int i = 0; i < last_idx; i++) {
1296       if (useful_member_set.test(i)) {
1297         if (_dead_node_list.test(i)) {
1298           if (_log != NULL) {
1299             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
1300           }
1301           if (PrintIdealNodeCount) {
1302             // Print the log message to tty
1303               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
1304               useful.at(i)->dump();
1305           }
1306         }
1307       }
1308       else if (! _dead_node_list.test(i)) {
1309         if (_log != NULL) {
1310           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
1311         }
1312         if (PrintIdealNodeCount) {
1313           // Print the log message to tty
1314           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
1315         }
1316       }
1317     }
1318     if (_log != NULL) {
1319       _log->tail("mismatched_nodes");
1320     }
1321   }
1322 }
1323 void Compile::record_modified_node(Node* n) {
1324   if (_modified_nodes != NULL && !_inlining_incrementally &&
1325       n->outcnt() != 0 && !n->is_Con()) {
1326     _modified_nodes->push(n);
1327   }
1328 }
1329 
1330 void Compile::remove_modified_node(Node* n) {
1331   if (_modified_nodes != NULL) {
1332     _modified_nodes->remove(n);
1333   }
1334 }
1335 #endif
1336 
1337 #ifndef PRODUCT
1338 void Compile::verify_top(Node* tn) const {
1339   if (tn != NULL) {
1340     assert(tn->is_Con(), "top node must be a constant");
1341     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1342     assert(tn->in(0) != NULL, "must have live top node");
1343   }
1344 }
1345 #endif
1346 
1347 
1348 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1349 
1350 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1351   guarantee(arr != NULL, "");
1352   int num_blocks = arr->length();
1353   if (grow_by < num_blocks)  grow_by = num_blocks;
1354   int num_notes = grow_by * _node_notes_block_size;
1355   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1356   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1357   while (num_notes > 0) {
1358     arr->append(notes);
1359     notes     += _node_notes_block_size;
1360     num_notes -= _node_notes_block_size;
1361   }
1362   assert(num_notes == 0, "exact multiple, please");
1363 }
1364 
1365 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1366   if (source == NULL || dest == NULL)  return false;
1367 
1368   if (dest->is_Con())
1369     return false;               // Do not push debug info onto constants.
1370 
1371 #ifdef ASSERT
1372   // Leave a bread crumb trail pointing to the original node:
1373   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1374     dest->set_debug_orig(source);
1375   }
1376 #endif
1377 
1378   if (node_note_array() == NULL)
1379     return false;               // Not collecting any notes now.
1380 
1381   // This is a copy onto a pre-existing node, which may already have notes.
1382   // If both nodes have notes, do not overwrite any pre-existing notes.
1383   Node_Notes* source_notes = node_notes_at(source->_idx);
1384   if (source_notes == NULL || source_notes->is_clear())  return false;
1385   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
1386   if (dest_notes == NULL || dest_notes->is_clear()) {
1387     return set_node_notes_at(dest->_idx, source_notes);
1388   }
1389 
1390   Node_Notes merged_notes = (*source_notes);
1391   // The order of operations here ensures that dest notes will win...
1392   merged_notes.update_from(dest_notes);
1393   return set_node_notes_at(dest->_idx, &merged_notes);
1394 }
1395 
1396 
1397 //--------------------------allow_range_check_smearing-------------------------
1398 // Gating condition for coalescing similar range checks.
1399 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1400 // single covering check that is at least as strong as any of them.
1401 // If the optimization succeeds, the simplified (strengthened) range check
1402 // will always succeed.  If it fails, we will deopt, and then give up
1403 // on the optimization.
1404 bool Compile::allow_range_check_smearing() const {
1405   // If this method has already thrown a range-check,
1406   // assume it was because we already tried range smearing
1407   // and it failed.
1408   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1409   return !already_trapped;
1410 }
1411 
1412 
1413 //------------------------------flatten_alias_type-----------------------------
1414 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1415   int offset = tj->offset();
1416   TypePtr::PTR ptr = tj->ptr();
1417 
1418   // Known instance (scalarizable allocation) alias only with itself.
1419   bool is_known_inst = tj->isa_oopptr() != NULL &&
1420                        tj->is_oopptr()->is_known_instance();
1421 
1422   // Process weird unsafe references.
1423   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1424     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
1425     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1426     tj = TypeOopPtr::BOTTOM;
1427     ptr = tj->ptr();
1428     offset = tj->offset();
1429   }
1430 
1431   // Array pointers need some flattening
1432   const TypeAryPtr *ta = tj->isa_aryptr();
1433   if (ta && ta->is_stable()) {
1434     // Erase stability property for alias analysis.
1435     tj = ta = ta->cast_to_stable(false);
1436   }
1437   if( ta && is_known_inst ) {
1438     if ( offset != Type::OffsetBot &&
1439          offset > arrayOopDesc::length_offset_in_bytes() ) {
1440       offset = Type::OffsetBot; // Flatten constant access into array body only
1441       tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
1442     }
1443   } else if( ta && _AliasLevel >= 2 ) {
1444     // For arrays indexed by constant indices, we flatten the alias
1445     // space to include all of the array body.  Only the header, klass
1446     // and array length can be accessed un-aliased.
1447     if( offset != Type::OffsetBot ) {
1448       if( ta->const_oop() ) { // MethodData* or Method*
1449         offset = Type::OffsetBot;   // Flatten constant access into array body
1450         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
1451       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1452         // range is OK as-is.
1453         tj = ta = TypeAryPtr::RANGE;
1454       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1455         tj = TypeInstPtr::KLASS; // all klass loads look alike
1456         ta = TypeAryPtr::RANGE; // generic ignored junk
1457         ptr = TypePtr::BotPTR;
1458       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1459         tj = TypeInstPtr::MARK;
1460         ta = TypeAryPtr::RANGE; // generic ignored junk
1461         ptr = TypePtr::BotPTR;
1462       } else {                  // Random constant offset into array body
1463         offset = Type::OffsetBot;   // Flatten constant access into array body
1464         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
1465       }
1466     }
1467     // Arrays of fixed size alias with arrays of unknown size.
1468     if (ta->size() != TypeInt::POS) {
1469       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1470       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
1471     }
1472     // Arrays of known objects become arrays of unknown objects.
1473     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1474       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1475       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1476     }
1477     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1478       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1479       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1480     }
1481     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1482     // cannot be distinguished by bytecode alone.
1483     if (ta->elem() == TypeInt::BOOL) {
1484       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1485       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1486       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
1487     }
1488     // During the 2nd round of IterGVN, NotNull castings are removed.
1489     // Make sure the Bottom and NotNull variants alias the same.
1490     // Also, make sure exact and non-exact variants alias the same.
1491     if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != NULL) {
1492       tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
1493     }
1494   }
1495 
1496   // Oop pointers need some flattening
1497   const TypeInstPtr *to = tj->isa_instptr();
1498   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1499     ciInstanceKlass *k = to->klass()->as_instance_klass();
1500     if( ptr == TypePtr::Constant ) {
1501       if (to->klass() != ciEnv::current()->Class_klass() ||
1502           offset < k->size_helper() * wordSize) {
1503         // No constant oop pointers (such as Strings); they alias with
1504         // unknown strings.
1505         assert(!is_known_inst, "not scalarizable allocation");
1506         tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1507       }
1508     } else if( is_known_inst ) {
1509       tj = to; // Keep NotNull and klass_is_exact for instance type
1510     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1511       // During the 2nd round of IterGVN, NotNull castings are removed.
1512       // Make sure the Bottom and NotNull variants alias the same.
1513       // Also, make sure exact and non-exact variants alias the same.
1514       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1515     }
1516     if (to->speculative() != NULL) {
1517       tj = to = TypeInstPtr::make(to->ptr(),to->klass(),to->klass_is_exact(),to->const_oop(),to->offset(), to->instance_id());
1518     }
1519     // Canonicalize the holder of this field
1520     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1521       // First handle header references such as a LoadKlassNode, even if the
1522       // object's klass is unloaded at compile time (4965979).
1523       if (!is_known_inst) { // Do it only for non-instance types
1524         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
1525       }
1526     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1527       // Static fields are in the space above the normal instance
1528       // fields in the java.lang.Class instance.
1529       if (to->klass() != ciEnv::current()->Class_klass()) {
1530         to = NULL;
1531         tj = TypeOopPtr::BOTTOM;
1532         offset = tj->offset();
1533       }
1534     } else {
1535       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1536       if (!k->equals(canonical_holder) || tj->offset() != offset) {
1537         if( is_known_inst ) {
1538           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
1539         } else {
1540           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
1541         }
1542       }
1543     }
1544   }
1545 
1546   // Klass pointers to object array klasses need some flattening
1547   const TypeKlassPtr *tk = tj->isa_klassptr();
1548   if( tk ) {
1549     // If we are referencing a field within a Klass, we need
1550     // to assume the worst case of an Object.  Both exact and
1551     // inexact types must flatten to the same alias class so
1552     // use NotNull as the PTR.
1553     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1554 
1555       tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
1556                                    TypeKlassPtr::OBJECT->klass(),
1557                                    offset);
1558     }
1559 
1560     ciKlass* klass = tk->klass();
1561     if( klass->is_obj_array_klass() ) {
1562       ciKlass* k = TypeAryPtr::OOPS->klass();
1563       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
1564         k = TypeInstPtr::BOTTOM->klass();
1565       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
1566     }
1567 
1568     // Check for precise loads from the primary supertype array and force them
1569     // to the supertype cache alias index.  Check for generic array loads from
1570     // the primary supertype array and also force them to the supertype cache
1571     // alias index.  Since the same load can reach both, we need to merge
1572     // these 2 disparate memories into the same alias class.  Since the
1573     // primary supertype array is read-only, there's no chance of confusion
1574     // where we bypass an array load and an array store.
1575     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1576     if (offset == Type::OffsetBot ||
1577         (offset >= primary_supers_offset &&
1578          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1579         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1580       offset = in_bytes(Klass::secondary_super_cache_offset());
1581       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
1582     }
1583   }
1584 
1585   // Flatten all Raw pointers together.
1586   if (tj->base() == Type::RawPtr)
1587     tj = TypeRawPtr::BOTTOM;
1588 
1589   if (tj->base() == Type::AnyPtr)
1590     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
1591 
1592   // Flatten all to bottom for now
1593   switch( _AliasLevel ) {
1594   case 0:
1595     tj = TypePtr::BOTTOM;
1596     break;
1597   case 1:                       // Flatten to: oop, static, field or array
1598     switch (tj->base()) {
1599     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
1600     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
1601     case Type::AryPtr:   // do not distinguish arrays at all
1602     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
1603     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1604     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
1605     default: ShouldNotReachHere();
1606     }
1607     break;
1608   case 2:                       // No collapsing at level 2; keep all splits
1609   case 3:                       // No collapsing at level 3; keep all splits
1610     break;
1611   default:
1612     Unimplemented();
1613   }
1614 
1615   offset = tj->offset();
1616   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1617 
1618   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1619           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1620           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1621           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1622           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1623           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1624           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr)  ,
1625           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1626   assert( tj->ptr() != TypePtr::TopPTR &&
1627           tj->ptr() != TypePtr::AnyNull &&
1628           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1629 //    assert( tj->ptr() != TypePtr::Constant ||
1630 //            tj->base() == Type::RawPtr ||
1631 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
1632 
1633   return tj;
1634 }
1635 
1636 void Compile::AliasType::Init(int i, const TypePtr* at) {
1637   _index = i;
1638   _adr_type = at;
1639   _field = NULL;
1640   _element = NULL;
1641   _is_rewritable = true; // default
1642   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1643   if (atoop != NULL && atoop->is_known_instance()) {
1644     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1645     _general_index = Compile::current()->get_alias_index(gt);
1646   } else {
1647     _general_index = 0;
1648   }
1649 }
1650 
1651 BasicType Compile::AliasType::basic_type() const {
1652   if (element() != NULL) {
1653     const Type* element = adr_type()->is_aryptr()->elem();
1654     return element->isa_narrowoop() ? T_OBJECT : element->array_element_basic_type();
1655   } if (field() != NULL) {
1656     return field()->layout_type();
1657   } else {
1658     return T_ILLEGAL; // unknown
1659   }
1660 }
1661 
1662 //---------------------------------print_on------------------------------------
1663 #ifndef PRODUCT
1664 void Compile::AliasType::print_on(outputStream* st) {
1665   if (index() < 10)
1666         st->print("@ <%d> ", index());
1667   else  st->print("@ <%d>",  index());
1668   st->print(is_rewritable() ? "   " : " RO");
1669   int offset = adr_type()->offset();
1670   if (offset == Type::OffsetBot)
1671         st->print(" +any");
1672   else  st->print(" +%-3d", offset);
1673   st->print(" in ");
1674   adr_type()->dump_on(st);
1675   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1676   if (field() != NULL && tjp) {
1677     if (tjp->klass()  != field()->holder() ||
1678         tjp->offset() != field()->offset_in_bytes()) {
1679       st->print(" != ");
1680       field()->print();
1681       st->print(" ***");
1682     }
1683   }
1684 }
1685 
1686 void print_alias_types() {
1687   Compile* C = Compile::current();
1688   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1689   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1690     C->alias_type(idx)->print_on(tty);
1691     tty->cr();
1692   }
1693 }
1694 #endif
1695 
1696 
1697 //----------------------------probe_alias_cache--------------------------------
1698 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1699   intptr_t key = (intptr_t) adr_type;
1700   key ^= key >> logAliasCacheSize;
1701   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1702 }
1703 
1704 
1705 //-----------------------------grow_alias_types--------------------------------
1706 void Compile::grow_alias_types() {
1707   const int old_ats  = _max_alias_types; // how many before?
1708   const int new_ats  = old_ats;          // how many more?
1709   const int grow_ats = old_ats+new_ats;  // how many now?
1710   _max_alias_types = grow_ats;
1711   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1712   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1713   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1714   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
1715 }
1716 
1717 
1718 //--------------------------------find_alias_type------------------------------
1719 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1720   if (_AliasLevel == 0)
1721     return alias_type(AliasIdxBot);
1722 
1723   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1724   if (ace->_adr_type == adr_type) {
1725     return alias_type(ace->_index);
1726   }
1727 
1728   // Handle special cases.
1729   if (adr_type == NULL)             return alias_type(AliasIdxTop);
1730   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
1731 
1732   // Do it the slow way.
1733   const TypePtr* flat = flatten_alias_type(adr_type);
1734 
1735 #ifdef ASSERT
1736   {
1737     ResourceMark rm;
1738     assert(flat == flatten_alias_type(flat), "not idempotent: adr_type = %s; flat = %s => %s",
1739            Type::str(adr_type), Type::str(flat), Type::str(flatten_alias_type(flat)));
1740     assert(flat != TypePtr::BOTTOM, "cannot alias-analyze an untyped ptr: adr_type = %s",
1741            Type::str(adr_type));
1742     if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1743       const TypeOopPtr* foop = flat->is_oopptr();
1744       // Scalarizable allocations have exact klass always.
1745       bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1746       const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1747       assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type: foop = %s; xoop = %s",
1748              Type::str(foop), Type::str(xoop));
1749     }
1750   }
1751 #endif
1752 
1753   int idx = AliasIdxTop;
1754   for (int i = 0; i < num_alias_types(); i++) {
1755     if (alias_type(i)->adr_type() == flat) {
1756       idx = i;
1757       break;
1758     }
1759   }
1760 
1761   if (idx == AliasIdxTop) {
1762     if (no_create)  return NULL;
1763     // Grow the array if necessary.
1764     if (_num_alias_types == _max_alias_types)  grow_alias_types();
1765     // Add a new alias type.
1766     idx = _num_alias_types++;
1767     _alias_types[idx]->Init(idx, flat);
1768     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
1769     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
1770     if (flat->isa_instptr()) {
1771       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1772           && flat->is_instptr()->klass() == env()->Class_klass())
1773         alias_type(idx)->set_rewritable(false);
1774     }
1775     if (flat->isa_aryptr()) {
1776 #ifdef ASSERT
1777       const int header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1778       // (T_BYTE has the weakest alignment and size restrictions...)
1779       assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
1780 #endif
1781       if (flat->offset() == TypePtr::OffsetBot) {
1782         alias_type(idx)->set_element(flat->is_aryptr()->elem());
1783       }
1784     }
1785     if (flat->isa_klassptr()) {
1786       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1787         alias_type(idx)->set_rewritable(false);
1788       if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
1789         alias_type(idx)->set_rewritable(false);
1790       if (flat->offset() == in_bytes(Klass::access_flags_offset()))
1791         alias_type(idx)->set_rewritable(false);
1792       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1793         alias_type(idx)->set_rewritable(false);
1794     }
1795     // %%% (We would like to finalize JavaThread::threadObj_offset(),
1796     // but the base pointer type is not distinctive enough to identify
1797     // references into JavaThread.)
1798 
1799     // Check for final fields.
1800     const TypeInstPtr* tinst = flat->isa_instptr();
1801     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1802       ciField* field;
1803       if (tinst->const_oop() != NULL &&
1804           tinst->klass() == ciEnv::current()->Class_klass() &&
1805           tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
1806         // static field
1807         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1808         field = k->get_field_by_offset(tinst->offset(), true);
1809       } else {
1810         ciInstanceKlass *k = tinst->klass()->as_instance_klass();
1811         field = k->get_field_by_offset(tinst->offset(), false);
1812       }
1813       assert(field == NULL ||
1814              original_field == NULL ||
1815              (field->holder() == original_field->holder() &&
1816               field->offset() == original_field->offset() &&
1817               field->is_static() == original_field->is_static()), "wrong field?");
1818       // Set field() and is_rewritable() attributes.
1819       if (field != NULL)  alias_type(idx)->set_field(field);
1820     }
1821   }
1822 
1823   // Fill the cache for next time.
1824   ace->_adr_type = adr_type;
1825   ace->_index    = idx;
1826   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
1827 
1828   // Might as well try to fill the cache for the flattened version, too.
1829   AliasCacheEntry* face = probe_alias_cache(flat);
1830   if (face->_adr_type == NULL) {
1831     face->_adr_type = flat;
1832     face->_index    = idx;
1833     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1834   }
1835 
1836   return alias_type(idx);
1837 }
1838 
1839 
1840 Compile::AliasType* Compile::alias_type(ciField* field) {
1841   const TypeOopPtr* t;
1842   if (field->is_static())
1843     t = TypeInstPtr::make(field->holder()->java_mirror());
1844   else
1845     t = TypeOopPtr::make_from_klass_raw(field->holder());
1846   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1847   assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
1848   return atp;
1849 }
1850 
1851 
1852 //------------------------------have_alias_type--------------------------------
1853 bool Compile::have_alias_type(const TypePtr* adr_type) {
1854   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1855   if (ace->_adr_type == adr_type) {
1856     return true;
1857   }
1858 
1859   // Handle special cases.
1860   if (adr_type == NULL)             return true;
1861   if (adr_type == TypePtr::BOTTOM)  return true;
1862 
1863   return find_alias_type(adr_type, true, NULL) != NULL;
1864 }
1865 
1866 //-----------------------------must_alias--------------------------------------
1867 // True if all values of the given address type are in the given alias category.
1868 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1869   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1870   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
1871   if (alias_idx == AliasIdxTop)         return false; // the empty category
1872   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1873 
1874   // the only remaining possible overlap is identity
1875   int adr_idx = get_alias_index(adr_type);
1876   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1877   assert(adr_idx == alias_idx ||
1878          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1879           && adr_type                       != TypeOopPtr::BOTTOM),
1880          "should not be testing for overlap with an unsafe pointer");
1881   return adr_idx == alias_idx;
1882 }
1883 
1884 //------------------------------can_alias--------------------------------------
1885 // True if any values of the given address type are in the given alias category.
1886 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1887   if (alias_idx == AliasIdxTop)         return false; // the empty category
1888   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
1889   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1890   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
1891 
1892   // the only remaining possible overlap is identity
1893   int adr_idx = get_alias_index(adr_type);
1894   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1895   return adr_idx == alias_idx;
1896 }
1897 
1898 
1899 
1900 //---------------------------pop_warm_call-------------------------------------
1901 WarmCallInfo* Compile::pop_warm_call() {
1902   WarmCallInfo* wci = _warm_calls;
1903   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
1904   return wci;
1905 }
1906 
1907 //----------------------------Inline_Warm--------------------------------------
1908 int Compile::Inline_Warm() {
1909   // If there is room, try to inline some more warm call sites.
1910   // %%% Do a graph index compaction pass when we think we're out of space?
1911   if (!InlineWarmCalls)  return 0;
1912 
1913   int calls_made_hot = 0;
1914   int room_to_grow   = NodeCountInliningCutoff - unique();
1915   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1916   int amount_grown   = 0;
1917   WarmCallInfo* call;
1918   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1919     int est_size = (int)call->size();
1920     if (est_size > (room_to_grow - amount_grown)) {
1921       // This one won't fit anyway.  Get rid of it.
1922       call->make_cold();
1923       continue;
1924     }
1925     call->make_hot();
1926     calls_made_hot++;
1927     amount_grown   += est_size;
1928     amount_to_grow -= est_size;
1929   }
1930 
1931   if (calls_made_hot > 0)  set_major_progress();
1932   return calls_made_hot;
1933 }
1934 
1935 
1936 //----------------------------Finish_Warm--------------------------------------
1937 void Compile::Finish_Warm() {
1938   if (!InlineWarmCalls)  return;
1939   if (failing())  return;
1940   if (warm_calls() == NULL)  return;
1941 
1942   // Clean up loose ends, if we are out of space for inlining.
1943   WarmCallInfo* call;
1944   while ((call = pop_warm_call()) != NULL) {
1945     call->make_cold();
1946   }
1947 }
1948 
1949 //---------------------cleanup_loop_predicates-----------------------
1950 // Remove the opaque nodes that protect the predicates so that all unused
1951 // checks and uncommon_traps will be eliminated from the ideal graph
1952 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1953   if (predicate_count()==0) return;
1954   for (int i = predicate_count(); i > 0; i--) {
1955     Node * n = predicate_opaque1_node(i-1);
1956     assert(n->Opcode() == Op_Opaque1, "must be");
1957     igvn.replace_node(n, n->in(1));
1958   }
1959   assert(predicate_count()==0, "should be clean!");
1960 }
1961 
1962 void Compile::add_range_check_cast(Node* n) {
1963   assert(n->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1964   assert(!_range_check_casts->contains(n), "duplicate entry in range check casts");
1965   _range_check_casts->append(n);
1966 }
1967 
1968 // Remove all range check dependent CastIINodes.
1969 void Compile::remove_range_check_casts(PhaseIterGVN &igvn) {
1970   for (int i = range_check_cast_count(); i > 0; i--) {
1971     Node* cast = range_check_cast_node(i-1);
1972     assert(cast->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1973     igvn.replace_node(cast, cast->in(1));
1974   }
1975   assert(range_check_cast_count() == 0, "should be empty");
1976 }
1977 
1978 void Compile::add_opaque4_node(Node* n) {
1979   assert(n->Opcode() == Op_Opaque4, "Opaque4 only");
1980   assert(!_opaque4_nodes->contains(n), "duplicate entry in Opaque4 list");
1981   _opaque4_nodes->append(n);
1982 }
1983 
1984 // Remove all Opaque4 nodes.
1985 void Compile::remove_opaque4_nodes(PhaseIterGVN &igvn) {
1986   for (int i = opaque4_count(); i > 0; i--) {
1987     Node* opaq = opaque4_node(i-1);
1988     assert(opaq->Opcode() == Op_Opaque4, "Opaque4 only");
1989     igvn.replace_node(opaq, opaq->in(2));
1990   }
1991   assert(opaque4_count() == 0, "should be empty");
1992 }
1993 
1994 // StringOpts and late inlining of string methods
1995 void Compile::inline_string_calls(bool parse_time) {
1996   {
1997     // remove useless nodes to make the usage analysis simpler
1998     ResourceMark rm;
1999     PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2000   }
2001 
2002   {
2003     ResourceMark rm;
2004     print_method(PHASE_BEFORE_STRINGOPTS, 3);
2005     PhaseStringOpts pso(initial_gvn(), for_igvn());
2006     print_method(PHASE_AFTER_STRINGOPTS, 3);
2007   }
2008 
2009   // now inline anything that we skipped the first time around
2010   if (!parse_time) {
2011     _late_inlines_pos = _late_inlines.length();
2012   }
2013 
2014   while (_string_late_inlines.length() > 0) {
2015     CallGenerator* cg = _string_late_inlines.pop();
2016     cg->do_late_inline();
2017     if (failing())  return;
2018   }
2019   _string_late_inlines.trunc_to(0);
2020 }
2021 
2022 // Late inlining of boxing methods
2023 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
2024   if (_boxing_late_inlines.length() > 0) {
2025     assert(has_boxed_value(), "inconsistent");
2026 
2027     PhaseGVN* gvn = initial_gvn();
2028     set_inlining_incrementally(true);
2029 
2030     assert( igvn._worklist.size() == 0, "should be done with igvn" );
2031     for_igvn()->clear();
2032     gvn->replace_with(&igvn);
2033 
2034     _late_inlines_pos = _late_inlines.length();
2035 
2036     while (_boxing_late_inlines.length() > 0) {
2037       CallGenerator* cg = _boxing_late_inlines.pop();
2038       cg->do_late_inline();
2039       if (failing())  return;
2040     }
2041     _boxing_late_inlines.trunc_to(0);
2042 
2043     {
2044       ResourceMark rm;
2045       PhaseRemoveUseless pru(gvn, for_igvn());
2046     }
2047 
2048     igvn = PhaseIterGVN(gvn);
2049     igvn.optimize();
2050 
2051     set_inlining_progress(false);
2052     set_inlining_incrementally(false);
2053   }
2054 }
2055 
2056 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
2057   assert(IncrementalInline, "incremental inlining should be on");
2058   PhaseGVN* gvn = initial_gvn();
2059 
2060   set_inlining_progress(false);
2061   for_igvn()->clear();
2062   gvn->replace_with(&igvn);
2063 
2064   {
2065     TracePhase tp("incrementalInline_inline", &timers[_t_incrInline_inline]);
2066     int i = 0;
2067     for (; i <_late_inlines.length() && !inlining_progress(); i++) {
2068       CallGenerator* cg = _late_inlines.at(i);
2069       _late_inlines_pos = i+1;
2070       cg->do_late_inline();
2071       if (failing())  return;
2072     }
2073     int j = 0;
2074     for (; i < _late_inlines.length(); i++, j++) {
2075       _late_inlines.at_put(j, _late_inlines.at(i));
2076     }
2077     _late_inlines.trunc_to(j);
2078   }
2079 
2080   {
2081     TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2082     ResourceMark rm;
2083     PhaseRemoveUseless pru(gvn, for_igvn());
2084   }
2085 
2086   {
2087     TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2088     igvn = PhaseIterGVN(gvn);
2089   }
2090 }
2091 
2092 // Perform incremental inlining until bound on number of live nodes is reached
2093 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
2094   TracePhase tp("incrementalInline", &timers[_t_incrInline]);
2095 
2096   PhaseGVN* gvn = initial_gvn();
2097 
2098   set_inlining_incrementally(true);
2099   set_inlining_progress(true);
2100   uint low_live_nodes = 0;
2101 
2102   while(inlining_progress() && _late_inlines.length() > 0) {
2103 
2104     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2105       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
2106         TracePhase tp("incrementalInline_ideal", &timers[_t_incrInline_ideal]);
2107         // PhaseIdealLoop is expensive so we only try it once we are
2108         // out of live nodes and we only try it again if the previous
2109         // helped got the number of nodes down significantly
2110         PhaseIdealLoop ideal_loop(igvn, LoopOptsNone);
2111         if (failing())  return;
2112         low_live_nodes = live_nodes();
2113         _major_progress = true;
2114       }
2115 
2116       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2117         break;
2118       }
2119     }
2120 
2121     inline_incrementally_one(igvn);
2122 
2123     if (failing())  return;
2124 
2125     {
2126       TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2127       igvn.optimize();
2128     }
2129 
2130     if (failing())  return;
2131   }
2132 
2133   assert( igvn._worklist.size() == 0, "should be done with igvn" );
2134 
2135   if (_string_late_inlines.length() > 0) {
2136     assert(has_stringbuilder(), "inconsistent");
2137     for_igvn()->clear();
2138     initial_gvn()->replace_with(&igvn);
2139 
2140     inline_string_calls(false);
2141 
2142     if (failing())  return;
2143 
2144     {
2145       TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2146       ResourceMark rm;
2147       PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2148     }
2149 
2150     {
2151       TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2152       igvn = PhaseIterGVN(gvn);
2153       igvn.optimize();
2154     }
2155   }
2156 
2157   set_inlining_incrementally(false);
2158 }
2159 
2160 
2161 bool Compile::optimize_loops(int& loop_opts_cnt, PhaseIterGVN& igvn, LoopOptsMode mode) {
2162   if(loop_opts_cnt > 0) {
2163     debug_only( int cnt = 0; );
2164     while(major_progress() && (loop_opts_cnt > 0)) {
2165       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2166       assert( cnt++ < 40, "infinite cycle in loop optimization" );
2167       PhaseIdealLoop ideal_loop(igvn, mode);
2168       loop_opts_cnt--;
2169       if (failing())  return false;
2170       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
2171     }
2172   }
2173   return true;
2174 }
2175 
2176 //------------------------------Optimize---------------------------------------
2177 // Given a graph, optimize it.
2178 void Compile::Optimize() {
2179   TracePhase tp("optimizer", &timers[_t_optimizer]);
2180 
2181 #ifndef PRODUCT
2182   if (_directive->BreakAtCompileOption) {
2183     BREAKPOINT;
2184   }
2185 
2186 #endif
2187 
2188 #ifdef ASSERT
2189   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2190   bs->verify_gc_barriers(true);
2191 #endif
2192 
2193   ResourceMark rm;
2194   int          loop_opts_cnt;
2195 
2196   print_inlining_reinit();
2197 
2198   NOT_PRODUCT( verify_graph_edges(); )
2199 
2200   print_method(PHASE_AFTER_PARSING);
2201 
2202  {
2203   // Iterative Global Value Numbering, including ideal transforms
2204   // Initialize IterGVN with types and values from parse-time GVN
2205   PhaseIterGVN igvn(initial_gvn());
2206 #ifdef ASSERT
2207   _modified_nodes = new (comp_arena()) Unique_Node_List(comp_arena());
2208 #endif
2209   {
2210     TracePhase tp("iterGVN", &timers[_t_iterGVN]);
2211     igvn.optimize();
2212   }
2213 
2214   if (failing())  return;
2215 
2216   print_method(PHASE_ITER_GVN1, 2);
2217 
2218   inline_incrementally(igvn);
2219 
2220   print_method(PHASE_INCREMENTAL_INLINE, 2);
2221 
2222   if (failing())  return;
2223 
2224   if (eliminate_boxing()) {
2225     // Inline valueOf() methods now.
2226     inline_boxing_calls(igvn);
2227 
2228     if (AlwaysIncrementalInline) {
2229       inline_incrementally(igvn);
2230     }
2231 
2232     print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
2233 
2234     if (failing())  return;
2235   }
2236 
2237   // Remove the speculative part of types and clean up the graph from
2238   // the extra CastPP nodes whose only purpose is to carry them. Do
2239   // that early so that optimizations are not disrupted by the extra
2240   // CastPP nodes.
2241   remove_speculative_types(igvn);
2242 
2243   // No more new expensive nodes will be added to the list from here
2244   // so keep only the actual candidates for optimizations.
2245   cleanup_expensive_nodes(igvn);
2246 
2247   if (!failing() && RenumberLiveNodes && live_nodes() + NodeLimitFudgeFactor < unique()) {
2248     Compile::TracePhase tp("", &timers[_t_renumberLive]);
2249     initial_gvn()->replace_with(&igvn);
2250     for_igvn()->clear();
2251     Unique_Node_List new_worklist(C->comp_arena());
2252     {
2253       ResourceMark rm;
2254       PhaseRenumberLive prl = PhaseRenumberLive(initial_gvn(), for_igvn(), &new_worklist);
2255     }
2256     set_for_igvn(&new_worklist);
2257     igvn = PhaseIterGVN(initial_gvn());
2258     igvn.optimize();
2259   }
2260 
2261   // Perform escape analysis
2262   if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
2263     if (has_loops()) {
2264       // Cleanup graph (remove dead nodes).
2265       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2266       PhaseIdealLoop ideal_loop(igvn, LoopOptsNone);
2267       if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
2268       if (failing())  return;
2269     }
2270     ConnectionGraph::do_analysis(this, &igvn);
2271 
2272     if (failing())  return;
2273 
2274     // Optimize out fields loads from scalar replaceable allocations.
2275     igvn.optimize();
2276     print_method(PHASE_ITER_GVN_AFTER_EA, 2);
2277 
2278     if (failing())  return;
2279 
2280     if (congraph() != NULL && macro_count() > 0) {
2281       TracePhase tp("macroEliminate", &timers[_t_macroEliminate]);
2282       PhaseMacroExpand mexp(igvn);
2283       mexp.eliminate_macro_nodes();
2284       igvn.set_delay_transform(false);
2285 
2286       igvn.optimize();
2287       print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
2288 
2289       if (failing())  return;
2290     }
2291   }
2292 
2293   // Loop transforms on the ideal graph.  Range Check Elimination,
2294   // peeling, unrolling, etc.
2295 
2296   // Set loop opts counter
2297   loop_opts_cnt = num_loop_opts();
2298   if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
2299     {
2300       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2301       PhaseIdealLoop ideal_loop(igvn, LoopOptsDefault);
2302       loop_opts_cnt--;
2303       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
2304       if (failing())  return;
2305     }
2306     // Loop opts pass if partial peeling occurred in previous pass
2307     if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
2308       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2309       PhaseIdealLoop ideal_loop(igvn, LoopOptsSkipSplitIf);
2310       loop_opts_cnt--;
2311       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
2312       if (failing())  return;
2313     }
2314     // Loop opts pass for loop-unrolling before CCP
2315     if(major_progress() && (loop_opts_cnt > 0)) {
2316       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2317       PhaseIdealLoop ideal_loop(igvn, LoopOptsSkipSplitIf);
2318       loop_opts_cnt--;
2319       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
2320     }
2321     if (!failing()) {
2322       // Verify that last round of loop opts produced a valid graph
2323       TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2324       PhaseIdealLoop::verify(igvn);
2325     }
2326   }
2327   if (failing())  return;
2328 
2329   // Conditional Constant Propagation;
2330   PhaseCCP ccp( &igvn );
2331   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
2332   {
2333     TracePhase tp("ccp", &timers[_t_ccp]);
2334     ccp.do_transform();
2335   }
2336   print_method(PHASE_CPP1, 2);
2337 
2338   assert( true, "Break here to ccp.dump_old2new_map()");
2339 
2340   // Iterative Global Value Numbering, including ideal transforms
2341   {
2342     TracePhase tp("iterGVN2", &timers[_t_iterGVN2]);
2343     igvn = ccp;
2344     igvn.optimize();
2345   }
2346 
2347   print_method(PHASE_ITER_GVN2, 2);
2348 
2349   if (failing())  return;
2350 
2351   // Loop transforms on the ideal graph.  Range Check Elimination,
2352   // peeling, unrolling, etc.
2353   if (!optimize_loops(loop_opts_cnt, igvn, LoopOptsDefault)) {
2354     return;
2355   }
2356 
2357 #if INCLUDE_ZGC
2358   if (UseZGC) {
2359     ZBarrierSetC2::find_dominating_barriers(igvn);
2360   }
2361 #endif
2362 
2363   if (failing())  return;
2364 
2365   // Ensure that major progress is now clear
2366   C->clear_major_progress();
2367 
2368   {
2369     // Verify that all previous optimizations produced a valid graph
2370     // at least to this point, even if no loop optimizations were done.
2371     TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2372     PhaseIdealLoop::verify(igvn);
2373   }
2374 
2375   if (range_check_cast_count() > 0) {
2376     // No more loop optimizations. Remove all range check dependent CastIINodes.
2377     C->remove_range_check_casts(igvn);
2378     igvn.optimize();
2379   }
2380 
2381 #ifdef ASSERT
2382   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2383   bs->verify_gc_barriers(false);
2384 #endif
2385 
2386   {
2387     TracePhase tp("macroExpand", &timers[_t_macroExpand]);
2388     PhaseMacroExpand  mex(igvn);
2389     print_method(PHASE_BEFORE_MACRO_EXPANSION, 2);
2390     if (mex.expand_macro_nodes()) {
2391       assert(failing(), "must bail out w/ explicit message");
2392       return;
2393     }
2394   }
2395 
2396   print_method(PHASE_BEFORE_BARRIER_EXPAND, 2);
2397 
2398 #if INCLUDE_SHENANDOAHGC
2399   if (UseShenandoahGC && ((ShenandoahBarrierSetC2*)BarrierSet::barrier_set()->barrier_set_c2())->expand_barriers(this, igvn)) {
2400     assert(failing(), "must bail out w/ explicit message");
2401     return;
2402   }
2403 #endif
2404 
2405   if (opaque4_count() > 0) {
2406     C->remove_opaque4_nodes(igvn);
2407     igvn.optimize();
2408   }
2409 
2410   DEBUG_ONLY( _modified_nodes = NULL; )
2411  } // (End scope of igvn; run destructor if necessary for asserts.)
2412 
2413  process_print_inlining();
2414  // A method with only infinite loops has no edges entering loops from root
2415  {
2416    TracePhase tp("graphReshape", &timers[_t_graphReshaping]);
2417    if (final_graph_reshaping()) {
2418      assert(failing(), "must bail out w/ explicit message");
2419      return;
2420    }
2421  }
2422 
2423  print_method(PHASE_OPTIMIZE_FINISHED, 2);
2424 }
2425 
2426 
2427 //------------------------------Code_Gen---------------------------------------
2428 // Given a graph, generate code for it
2429 void Compile::Code_Gen() {
2430   if (failing()) {
2431     return;
2432   }
2433 
2434   // Perform instruction selection.  You might think we could reclaim Matcher
2435   // memory PDQ, but actually the Matcher is used in generating spill code.
2436   // Internals of the Matcher (including some VectorSets) must remain live
2437   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
2438   // set a bit in reclaimed memory.
2439 
2440   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2441   // nodes.  Mapping is only valid at the root of each matched subtree.
2442   NOT_PRODUCT( verify_graph_edges(); )
2443 
2444   Matcher matcher;
2445   _matcher = &matcher;
2446   {
2447     TracePhase tp("matcher", &timers[_t_matcher]);
2448     matcher.match();
2449   }
2450   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2451   // nodes.  Mapping is only valid at the root of each matched subtree.
2452   NOT_PRODUCT( verify_graph_edges(); )
2453 
2454   // If you have too many nodes, or if matching has failed, bail out
2455   check_node_count(0, "out of nodes matching instructions");
2456   if (failing()) {
2457     return;
2458   }
2459 
2460   print_method(PHASE_MATCHING, 2);
2461 
2462   // Build a proper-looking CFG
2463   PhaseCFG cfg(node_arena(), root(), matcher);
2464   _cfg = &cfg;
2465   {
2466     TracePhase tp("scheduler", &timers[_t_scheduler]);
2467     bool success = cfg.do_global_code_motion();
2468     if (!success) {
2469       return;
2470     }
2471 
2472     print_method(PHASE_GLOBAL_CODE_MOTION, 2);
2473     NOT_PRODUCT( verify_graph_edges(); )
2474     debug_only( cfg.verify(); )
2475   }
2476 
2477   PhaseChaitin regalloc(unique(), cfg, matcher, false);
2478   _regalloc = &regalloc;
2479   {
2480     TracePhase tp("regalloc", &timers[_t_registerAllocation]);
2481     // Perform register allocation.  After Chaitin, use-def chains are
2482     // no longer accurate (at spill code) and so must be ignored.
2483     // Node->LRG->reg mappings are still accurate.
2484     _regalloc->Register_Allocate();
2485 
2486     // Bail out if the allocator builds too many nodes
2487     if (failing()) {
2488       return;
2489     }
2490   }
2491 
2492   // Prior to register allocation we kept empty basic blocks in case the
2493   // the allocator needed a place to spill.  After register allocation we
2494   // are not adding any new instructions.  If any basic block is empty, we
2495   // can now safely remove it.
2496   {
2497     TracePhase tp("blockOrdering", &timers[_t_blockOrdering]);
2498     cfg.remove_empty_blocks();
2499     if (do_freq_based_layout()) {
2500       PhaseBlockLayout layout(cfg);
2501     } else {
2502       cfg.set_loop_alignment();
2503     }
2504     cfg.fixup_flow();
2505   }
2506 
2507   // Apply peephole optimizations
2508   if( OptoPeephole ) {
2509     TracePhase tp("peephole", &timers[_t_peephole]);
2510     PhasePeephole peep( _regalloc, cfg);
2511     peep.do_transform();
2512   }
2513 
2514   // Do late expand if CPU requires this.
2515   if (Matcher::require_postalloc_expand) {
2516     TracePhase tp("postalloc_expand", &timers[_t_postalloc_expand]);
2517     cfg.postalloc_expand(_regalloc);
2518   }
2519 
2520   // Convert Nodes to instruction bits in a buffer
2521   {
2522     TraceTime tp("output", &timers[_t_output], CITime);
2523     Output();
2524   }
2525 
2526   print_method(PHASE_FINAL_CODE);
2527 
2528   // He's dead, Jim.
2529   _cfg     = (PhaseCFG*)((intptr_t)0xdeadbeef);
2530   _regalloc = (PhaseChaitin*)((intptr_t)0xdeadbeef);
2531 }
2532 
2533 
2534 //------------------------------dump_asm---------------------------------------
2535 // Dump formatted assembly
2536 #ifndef PRODUCT
2537 void Compile::dump_asm(int *pcs, uint pc_limit) {
2538   bool cut_short = false;
2539   tty->print_cr("#");
2540   tty->print("#  ");  _tf->dump();  tty->cr();
2541   tty->print_cr("#");
2542 
2543   // For all blocks
2544   int pc = 0x0;                 // Program counter
2545   char starts_bundle = ' ';
2546   _regalloc->dump_frame();
2547 
2548   Node *n = NULL;
2549   for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
2550     if (VMThread::should_terminate()) {
2551       cut_short = true;
2552       break;
2553     }
2554     Block* block = _cfg->get_block(i);
2555     if (block->is_connector() && !Verbose) {
2556       continue;
2557     }
2558     n = block->head();
2559     if (pcs && n->_idx < pc_limit) {
2560       tty->print("%3.3x   ", pcs[n->_idx]);
2561     } else {
2562       tty->print("      ");
2563     }
2564     block->dump_head(_cfg);
2565     if (block->is_connector()) {
2566       tty->print_cr("        # Empty connector block");
2567     } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
2568       tty->print_cr("        # Block is sole successor of call");
2569     }
2570 
2571     // For all instructions
2572     Node *delay = NULL;
2573     for (uint j = 0; j < block->number_of_nodes(); j++) {
2574       if (VMThread::should_terminate()) {
2575         cut_short = true;
2576         break;
2577       }
2578       n = block->get_node(j);
2579       if (valid_bundle_info(n)) {
2580         Bundle* bundle = node_bundling(n);
2581         if (bundle->used_in_unconditional_delay()) {
2582           delay = n;
2583           continue;
2584         }
2585         if (bundle->starts_bundle()) {
2586           starts_bundle = '+';
2587         }
2588       }
2589 
2590       if (WizardMode) {
2591         n->dump();
2592       }
2593 
2594       if( !n->is_Region() &&    // Dont print in the Assembly
2595           !n->is_Phi() &&       // a few noisely useless nodes
2596           !n->is_Proj() &&
2597           !n->is_MachTemp() &&
2598           !n->is_SafePointScalarObject() &&
2599           !n->is_Catch() &&     // Would be nice to print exception table targets
2600           !n->is_MergeMem() &&  // Not very interesting
2601           !n->is_top() &&       // Debug info table constants
2602           !(n->is_Con() && !n->is_Mach())// Debug info table constants
2603           ) {
2604         if (pcs && n->_idx < pc_limit)
2605           tty->print("%3.3x", pcs[n->_idx]);
2606         else
2607           tty->print("   ");
2608         tty->print(" %c ", starts_bundle);
2609         starts_bundle = ' ';
2610         tty->print("\t");
2611         n->format(_regalloc, tty);
2612         tty->cr();
2613       }
2614 
2615       // If we have an instruction with a delay slot, and have seen a delay,
2616       // then back up and print it
2617       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
2618         assert(delay != NULL, "no unconditional delay instruction");
2619         if (WizardMode) delay->dump();
2620 
2621         if (node_bundling(delay)->starts_bundle())
2622           starts_bundle = '+';
2623         if (pcs && n->_idx < pc_limit)
2624           tty->print("%3.3x", pcs[n->_idx]);
2625         else
2626           tty->print("   ");
2627         tty->print(" %c ", starts_bundle);
2628         starts_bundle = ' ';
2629         tty->print("\t");
2630         delay->format(_regalloc, tty);
2631         tty->cr();
2632         delay = NULL;
2633       }
2634 
2635       // Dump the exception table as well
2636       if( n->is_Catch() && (Verbose || WizardMode) ) {
2637         // Print the exception table for this offset
2638         _handler_table.print_subtable_for(pc);
2639       }
2640     }
2641 
2642     if (pcs && n->_idx < pc_limit)
2643       tty->print_cr("%3.3x", pcs[n->_idx]);
2644     else
2645       tty->cr();
2646 
2647     assert(cut_short || delay == NULL, "no unconditional delay branch");
2648 
2649   } // End of per-block dump
2650   tty->cr();
2651 
2652   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
2653 }
2654 #endif
2655 
2656 //------------------------------Final_Reshape_Counts---------------------------
2657 // This class defines counters to help identify when a method
2658 // may/must be executed using hardware with only 24-bit precision.
2659 struct Final_Reshape_Counts : public StackObj {
2660   int  _call_count;             // count non-inlined 'common' calls
2661   int  _float_count;            // count float ops requiring 24-bit precision
2662   int  _double_count;           // count double ops requiring more precision
2663   int  _java_call_count;        // count non-inlined 'java' calls
2664   int  _inner_loop_count;       // count loops which need alignment
2665   VectorSet _visited;           // Visitation flags
2666   Node_List _tests;             // Set of IfNodes & PCTableNodes
2667 
2668   Final_Reshape_Counts() :
2669     _call_count(0), _float_count(0), _double_count(0),
2670     _java_call_count(0), _inner_loop_count(0),
2671     _visited( Thread::current()->resource_area() ) { }
2672 
2673   void inc_call_count  () { _call_count  ++; }
2674   void inc_float_count () { _float_count ++; }
2675   void inc_double_count() { _double_count++; }
2676   void inc_java_call_count() { _java_call_count++; }
2677   void inc_inner_loop_count() { _inner_loop_count++; }
2678 
2679   int  get_call_count  () const { return _call_count  ; }
2680   int  get_float_count () const { return _float_count ; }
2681   int  get_double_count() const { return _double_count; }
2682   int  get_java_call_count() const { return _java_call_count; }
2683   int  get_inner_loop_count() const { return _inner_loop_count; }
2684 };
2685 
2686 #ifdef ASSERT
2687 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
2688   ciInstanceKlass *k = tp->klass()->as_instance_klass();
2689   // Make sure the offset goes inside the instance layout.
2690   return k->contains_field_offset(tp->offset());
2691   // Note that OffsetBot and OffsetTop are very negative.
2692 }
2693 #endif
2694 
2695 // Eliminate trivially redundant StoreCMs and accumulate their
2696 // precedence edges.
2697 void Compile::eliminate_redundant_card_marks(Node* n) {
2698   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
2699   if (n->in(MemNode::Address)->outcnt() > 1) {
2700     // There are multiple users of the same address so it might be
2701     // possible to eliminate some of the StoreCMs
2702     Node* mem = n->in(MemNode::Memory);
2703     Node* adr = n->in(MemNode::Address);
2704     Node* val = n->in(MemNode::ValueIn);
2705     Node* prev = n;
2706     bool done = false;
2707     // Walk the chain of StoreCMs eliminating ones that match.  As
2708     // long as it's a chain of single users then the optimization is
2709     // safe.  Eliminating partially redundant StoreCMs would require
2710     // cloning copies down the other paths.
2711     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
2712       if (adr == mem->in(MemNode::Address) &&
2713           val == mem->in(MemNode::ValueIn)) {
2714         // redundant StoreCM
2715         if (mem->req() > MemNode::OopStore) {
2716           // Hasn't been processed by this code yet.
2717           n->add_prec(mem->in(MemNode::OopStore));
2718         } else {
2719           // Already converted to precedence edge
2720           for (uint i = mem->req(); i < mem->len(); i++) {
2721             // Accumulate any precedence edges
2722             if (mem->in(i) != NULL) {
2723               n->add_prec(mem->in(i));
2724             }
2725           }
2726           // Everything above this point has been processed.
2727           done = true;
2728         }
2729         // Eliminate the previous StoreCM
2730         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
2731         assert(mem->outcnt() == 0, "should be dead");
2732         mem->disconnect_inputs(NULL, this);
2733       } else {
2734         prev = mem;
2735       }
2736       mem = prev->in(MemNode::Memory);
2737     }
2738   }
2739 }
2740 
2741 //------------------------------final_graph_reshaping_impl----------------------
2742 // Implement items 1-5 from final_graph_reshaping below.
2743 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
2744 
2745   if ( n->outcnt() == 0 ) return; // dead node
2746   uint nop = n->Opcode();
2747 
2748   // Check for 2-input instruction with "last use" on right input.
2749   // Swap to left input.  Implements item (2).
2750   if( n->req() == 3 &&          // two-input instruction
2751       n->in(1)->outcnt() > 1 && // left use is NOT a last use
2752       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
2753       n->in(2)->outcnt() == 1 &&// right use IS a last use
2754       !n->in(2)->is_Con() ) {   // right use is not a constant
2755     // Check for commutative opcode
2756     switch( nop ) {
2757     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
2758     case Op_MaxI:  case Op_MinI:
2759     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
2760     case Op_AndL:  case Op_XorL:  case Op_OrL:
2761     case Op_AndI:  case Op_XorI:  case Op_OrI: {
2762       // Move "last use" input to left by swapping inputs
2763       n->swap_edges(1, 2);
2764       break;
2765     }
2766     default:
2767       break;
2768     }
2769   }
2770 
2771 #ifdef ASSERT
2772   if( n->is_Mem() ) {
2773     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
2774     assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
2775             // oop will be recorded in oop map if load crosses safepoint
2776             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
2777                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
2778             "raw memory operations should have control edge");
2779   }
2780   if (n->is_MemBar()) {
2781     MemBarNode* mb = n->as_MemBar();
2782     if (mb->trailing_store() || mb->trailing_load_store()) {
2783       assert(mb->leading_membar()->trailing_membar() == mb, "bad membar pair");
2784       Node* mem = mb->in(MemBarNode::Precedent);
2785       assert((mb->trailing_store() && mem->is_Store() && mem->as_Store()->is_release()) ||
2786              (mb->trailing_load_store() && mem->is_LoadStore()), "missing mem op");
2787     } else if (mb->leading()) {
2788       assert(mb->trailing_membar()->leading_membar() == mb, "bad membar pair");
2789     }
2790   }
2791 #endif
2792   // Count FPU ops and common calls, implements item (3)
2793   switch( nop ) {
2794   // Count all float operations that may use FPU
2795   case Op_AddF:
2796   case Op_SubF:
2797   case Op_MulF:
2798   case Op_DivF:
2799   case Op_NegF:
2800   case Op_ModF:
2801   case Op_ConvI2F:
2802   case Op_ConF:
2803   case Op_CmpF:
2804   case Op_CmpF3:
2805   // case Op_ConvL2F: // longs are split into 32-bit halves
2806     frc.inc_float_count();
2807     break;
2808 
2809   case Op_ConvF2D:
2810   case Op_ConvD2F:
2811     frc.inc_float_count();
2812     frc.inc_double_count();
2813     break;
2814 
2815   // Count all double operations that may use FPU
2816   case Op_AddD:
2817   case Op_SubD:
2818   case Op_MulD:
2819   case Op_DivD:
2820   case Op_NegD:
2821   case Op_ModD:
2822   case Op_ConvI2D:
2823   case Op_ConvD2I:
2824   // case Op_ConvL2D: // handled by leaf call
2825   // case Op_ConvD2L: // handled by leaf call
2826   case Op_ConD:
2827   case Op_CmpD:
2828   case Op_CmpD3:
2829     frc.inc_double_count();
2830     break;
2831   case Op_Opaque1:              // Remove Opaque Nodes before matching
2832   case Op_Opaque2:              // Remove Opaque Nodes before matching
2833   case Op_Opaque3:
2834     n->subsume_by(n->in(1), this);
2835     break;
2836   case Op_CallStaticJava:
2837   case Op_CallJava:
2838   case Op_CallDynamicJava:
2839     frc.inc_java_call_count(); // Count java call site;
2840   case Op_CallRuntime:
2841   case Op_CallLeaf:
2842   case Op_CallLeafNoFP: {
2843     assert (n->is_Call(), "");
2844     CallNode *call = n->as_Call();
2845 #if INCLUDE_SHENANDOAHGC
2846     if (UseShenandoahGC && ShenandoahBarrierSetC2::is_shenandoah_wb_pre_call(call)) {
2847       uint cnt = ShenandoahBarrierSetC2::write_ref_field_pre_entry_Type()->domain()->cnt();
2848       if (call->req() > cnt) {
2849         assert(call->req() == cnt+1, "only one extra input");
2850         Node* addp = call->in(cnt);
2851         assert(!ShenandoahBarrierSetC2::has_only_shenandoah_wb_pre_uses(addp), "useless address computation?");
2852         call->del_req(cnt);
2853       }
2854     }
2855 #endif
2856     // Count call sites where the FP mode bit would have to be flipped.
2857     // Do not count uncommon runtime calls:
2858     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
2859     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
2860     if (!call->is_CallStaticJava() || !call->as_CallStaticJava()->_name) {
2861       frc.inc_call_count();   // Count the call site
2862     } else {                  // See if uncommon argument is shared
2863       Node *n = call->in(TypeFunc::Parms);
2864       int nop = n->Opcode();
2865       // Clone shared simple arguments to uncommon calls, item (1).
2866       if (n->outcnt() > 1 &&
2867           !n->is_Proj() &&
2868           nop != Op_CreateEx &&
2869           nop != Op_CheckCastPP &&
2870           nop != Op_DecodeN &&
2871           nop != Op_DecodeNKlass &&
2872           !n->is_Mem() &&
2873           !n->is_Phi()) {
2874         Node *x = n->clone();
2875         call->set_req(TypeFunc::Parms, x);
2876       }
2877     }
2878     break;
2879   }
2880 
2881   case Op_StoreD:
2882   case Op_LoadD:
2883   case Op_LoadD_unaligned:
2884     frc.inc_double_count();
2885     goto handle_mem;
2886   case Op_StoreF:
2887   case Op_LoadF:
2888     frc.inc_float_count();
2889     goto handle_mem;
2890 
2891   case Op_StoreCM:
2892     {
2893       // Convert OopStore dependence into precedence edge
2894       Node* prec = n->in(MemNode::OopStore);
2895       n->del_req(MemNode::OopStore);
2896       n->add_prec(prec);
2897       eliminate_redundant_card_marks(n);
2898     }
2899 
2900     // fall through
2901 
2902   case Op_StoreB:
2903   case Op_StoreC:
2904   case Op_StorePConditional:
2905   case Op_StoreI:
2906   case Op_StoreL:
2907   case Op_StoreIConditional:
2908   case Op_StoreLConditional:
2909   case Op_CompareAndSwapB:
2910   case Op_CompareAndSwapS:
2911   case Op_CompareAndSwapI:
2912   case Op_CompareAndSwapL:
2913   case Op_CompareAndSwapP:
2914   case Op_CompareAndSwapN:
2915   case Op_WeakCompareAndSwapB:
2916   case Op_WeakCompareAndSwapS:
2917   case Op_WeakCompareAndSwapI:
2918   case Op_WeakCompareAndSwapL:
2919   case Op_WeakCompareAndSwapP:
2920   case Op_WeakCompareAndSwapN:
2921   case Op_CompareAndExchangeB:
2922   case Op_CompareAndExchangeS:
2923   case Op_CompareAndExchangeI:
2924   case Op_CompareAndExchangeL:
2925   case Op_CompareAndExchangeP:
2926   case Op_CompareAndExchangeN:
2927   case Op_GetAndAddS:
2928   case Op_GetAndAddB:
2929   case Op_GetAndAddI:
2930   case Op_GetAndAddL:
2931   case Op_GetAndSetS:
2932   case Op_GetAndSetB:
2933   case Op_GetAndSetI:
2934   case Op_GetAndSetL:
2935   case Op_GetAndSetP:
2936   case Op_GetAndSetN:
2937   case Op_StoreP:
2938   case Op_StoreN:
2939   case Op_StoreNKlass:
2940   case Op_LoadB:
2941   case Op_LoadUB:
2942   case Op_LoadUS:
2943   case Op_LoadI:
2944   case Op_LoadKlass:
2945   case Op_LoadNKlass:
2946   case Op_LoadL:
2947   case Op_LoadL_unaligned:
2948   case Op_LoadPLocked:
2949   case Op_LoadP:
2950 #if INCLUDE_ZGC
2951   case Op_LoadBarrierSlowReg:
2952   case Op_LoadBarrierWeakSlowReg:
2953 #endif
2954   case Op_LoadN:
2955   case Op_LoadRange:
2956   case Op_LoadS: {
2957   handle_mem:
2958 #ifdef ASSERT
2959     if( VerifyOptoOopOffsets ) {
2960       assert( n->is_Mem(), "" );
2961       MemNode *mem  = (MemNode*)n;
2962       // Check to see if address types have grounded out somehow.
2963       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
2964       assert( !tp || oop_offset_is_sane(tp), "" );
2965     }
2966 #endif
2967     break;
2968   }
2969 
2970   case Op_AddP: {               // Assert sane base pointers
2971     Node *addp = n->in(AddPNode::Address);
2972     assert( !addp->is_AddP() ||
2973             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
2974             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
2975             "Base pointers must match (addp %u)", addp->_idx );
2976 #ifdef _LP64
2977     if ((UseCompressedOops || UseCompressedClassPointers) &&
2978         addp->Opcode() == Op_ConP &&
2979         addp == n->in(AddPNode::Base) &&
2980         n->in(AddPNode::Offset)->is_Con()) {
2981       // If the transformation of ConP to ConN+DecodeN is beneficial depends
2982       // on the platform and on the compressed oops mode.
2983       // Use addressing with narrow klass to load with offset on x86.
2984       // Some platforms can use the constant pool to load ConP.
2985       // Do this transformation here since IGVN will convert ConN back to ConP.
2986       const Type* t = addp->bottom_type();
2987       bool is_oop   = t->isa_oopptr() != NULL;
2988       bool is_klass = t->isa_klassptr() != NULL;
2989 
2990       if ((is_oop   && Matcher::const_oop_prefer_decode()  ) ||
2991           (is_klass && Matcher::const_klass_prefer_decode())) {
2992         Node* nn = NULL;
2993 
2994         int op = is_oop ? Op_ConN : Op_ConNKlass;
2995 
2996         // Look for existing ConN node of the same exact type.
2997         Node* r  = root();
2998         uint cnt = r->outcnt();
2999         for (uint i = 0; i < cnt; i++) {
3000           Node* m = r->raw_out(i);
3001           if (m!= NULL && m->Opcode() == op &&
3002               m->bottom_type()->make_ptr() == t) {
3003             nn = m;
3004             break;
3005           }
3006         }
3007         if (nn != NULL) {
3008           // Decode a narrow oop to match address
3009           // [R12 + narrow_oop_reg<<3 + offset]
3010           if (is_oop) {
3011             nn = new DecodeNNode(nn, t);
3012           } else {
3013             nn = new DecodeNKlassNode(nn, t);
3014           }
3015           // Check for succeeding AddP which uses the same Base.
3016           // Otherwise we will run into the assertion above when visiting that guy.
3017           for (uint i = 0; i < n->outcnt(); ++i) {
3018             Node *out_i = n->raw_out(i);
3019             if (out_i && out_i->is_AddP() && out_i->in(AddPNode::Base) == addp) {
3020               out_i->set_req(AddPNode::Base, nn);
3021 #ifdef ASSERT
3022               for (uint j = 0; j < out_i->outcnt(); ++j) {
3023                 Node *out_j = out_i->raw_out(j);
3024                 assert(out_j == NULL || !out_j->is_AddP() || out_j->in(AddPNode::Base) != addp,
3025                        "more than 2 AddP nodes in a chain (out_j %u)", out_j->_idx);
3026               }
3027 #endif
3028             }
3029           }
3030           n->set_req(AddPNode::Base, nn);
3031           n->set_req(AddPNode::Address, nn);
3032           if (addp->outcnt() == 0) {
3033             addp->disconnect_inputs(NULL, this);
3034           }
3035         }
3036       }
3037     }
3038 #endif
3039     // platform dependent reshaping of the address expression
3040     reshape_address(n->as_AddP());
3041     break;
3042   }
3043 
3044   case Op_CastPP: {
3045     // Remove CastPP nodes to gain more freedom during scheduling but
3046     // keep the dependency they encode as control or precedence edges
3047     // (if control is set already) on memory operations. Some CastPP
3048     // nodes don't have a control (don't carry a dependency): skip
3049     // those.
3050     if (n->in(0) != NULL) {
3051       ResourceMark rm;
3052       Unique_Node_List wq;
3053       wq.push(n);
3054       for (uint next = 0; next < wq.size(); ++next) {
3055         Node *m = wq.at(next);
3056         for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
3057           Node* use = m->fast_out(i);
3058           if (use->is_Mem() || use->is_EncodeNarrowPtr()) {
3059             use->ensure_control_or_add_prec(n->in(0));
3060           } else {
3061             switch(use->Opcode()) {
3062             case Op_AddP:
3063             case Op_DecodeN:
3064             case Op_DecodeNKlass:
3065             case Op_CheckCastPP:
3066             case Op_CastPP:
3067               wq.push(use);
3068               break;
3069             }
3070           }
3071         }
3072       }
3073     }
3074     const bool is_LP64 = LP64_ONLY(true) NOT_LP64(false);
3075     if (is_LP64 && n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
3076       Node* in1 = n->in(1);
3077       const Type* t = n->bottom_type();
3078       Node* new_in1 = in1->clone();
3079       new_in1->as_DecodeN()->set_type(t);
3080 
3081       if (!Matcher::narrow_oop_use_complex_address()) {
3082         //
3083         // x86, ARM and friends can handle 2 adds in addressing mode
3084         // and Matcher can fold a DecodeN node into address by using
3085         // a narrow oop directly and do implicit NULL check in address:
3086         //
3087         // [R12 + narrow_oop_reg<<3 + offset]
3088         // NullCheck narrow_oop_reg
3089         //
3090         // On other platforms (Sparc) we have to keep new DecodeN node and
3091         // use it to do implicit NULL check in address:
3092         //
3093         // decode_not_null narrow_oop_reg, base_reg
3094         // [base_reg + offset]
3095         // NullCheck base_reg
3096         //
3097         // Pin the new DecodeN node to non-null path on these platform (Sparc)
3098         // to keep the information to which NULL check the new DecodeN node
3099         // corresponds to use it as value in implicit_null_check().
3100         //
3101         new_in1->set_req(0, n->in(0));
3102       }
3103 
3104       n->subsume_by(new_in1, this);
3105       if (in1->outcnt() == 0) {
3106         in1->disconnect_inputs(NULL, this);
3107       }
3108     } else {
3109       n->subsume_by(n->in(1), this);
3110       if (n->outcnt() == 0) {
3111         n->disconnect_inputs(NULL, this);
3112       }
3113     }
3114     break;
3115   }
3116 #ifdef _LP64
3117   case Op_CmpP:
3118     // Do this transformation here to preserve CmpPNode::sub() and
3119     // other TypePtr related Ideal optimizations (for example, ptr nullness).
3120     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
3121       Node* in1 = n->in(1);
3122       Node* in2 = n->in(2);
3123       if (!in1->is_DecodeNarrowPtr()) {
3124         in2 = in1;
3125         in1 = n->in(2);
3126       }
3127       assert(in1->is_DecodeNarrowPtr(), "sanity");
3128 
3129       Node* new_in2 = NULL;
3130       if (in2->is_DecodeNarrowPtr()) {
3131         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
3132         new_in2 = in2->in(1);
3133       } else if (in2->Opcode() == Op_ConP) {
3134         const Type* t = in2->bottom_type();
3135         if (t == TypePtr::NULL_PTR) {
3136           assert(in1->is_DecodeN(), "compare klass to null?");
3137           // Don't convert CmpP null check into CmpN if compressed
3138           // oops implicit null check is not generated.
3139           // This will allow to generate normal oop implicit null check.
3140           if (Matcher::gen_narrow_oop_implicit_null_checks())
3141             new_in2 = ConNode::make(TypeNarrowOop::NULL_PTR);
3142           //
3143           // This transformation together with CastPP transformation above
3144           // will generated code for implicit NULL checks for compressed oops.
3145           //
3146           // The original code after Optimize()
3147           //
3148           //    LoadN memory, narrow_oop_reg
3149           //    decode narrow_oop_reg, base_reg
3150           //    CmpP base_reg, NULL
3151           //    CastPP base_reg // NotNull
3152           //    Load [base_reg + offset], val_reg
3153           //
3154           // after these transformations will be
3155           //
3156           //    LoadN memory, narrow_oop_reg
3157           //    CmpN narrow_oop_reg, NULL
3158           //    decode_not_null narrow_oop_reg, base_reg
3159           //    Load [base_reg + offset], val_reg
3160           //
3161           // and the uncommon path (== NULL) will use narrow_oop_reg directly
3162           // since narrow oops can be used in debug info now (see the code in
3163           // final_graph_reshaping_walk()).
3164           //
3165           // At the end the code will be matched to
3166           // on x86:
3167           //
3168           //    Load_narrow_oop memory, narrow_oop_reg
3169           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
3170           //    NullCheck narrow_oop_reg
3171           //
3172           // and on sparc:
3173           //
3174           //    Load_narrow_oop memory, narrow_oop_reg
3175           //    decode_not_null narrow_oop_reg, base_reg
3176           //    Load [base_reg + offset], val_reg
3177           //    NullCheck base_reg
3178           //
3179         } else if (t->isa_oopptr()) {
3180           new_in2 = ConNode::make(t->make_narrowoop());
3181         } else if (t->isa_klassptr()) {
3182           new_in2 = ConNode::make(t->make_narrowklass());
3183         }
3184       }
3185       if (new_in2 != NULL) {
3186         Node* cmpN = new CmpNNode(in1->in(1), new_in2);
3187         n->subsume_by(cmpN, this);
3188         if (in1->outcnt() == 0) {
3189           in1->disconnect_inputs(NULL, this);
3190         }
3191         if (in2->outcnt() == 0) {
3192           in2->disconnect_inputs(NULL, this);
3193         }
3194       }
3195     }
3196     break;
3197 
3198   case Op_DecodeN:
3199   case Op_DecodeNKlass:
3200     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
3201     // DecodeN could be pinned when it can't be fold into
3202     // an address expression, see the code for Op_CastPP above.
3203     assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
3204     break;
3205 
3206   case Op_EncodeP:
3207   case Op_EncodePKlass: {
3208     Node* in1 = n->in(1);
3209     if (in1->is_DecodeNarrowPtr()) {
3210       n->subsume_by(in1->in(1), this);
3211     } else if (in1->Opcode() == Op_ConP) {
3212       const Type* t = in1->bottom_type();
3213       if (t == TypePtr::NULL_PTR) {
3214         assert(t->isa_oopptr(), "null klass?");
3215         n->subsume_by(ConNode::make(TypeNarrowOop::NULL_PTR), this);
3216       } else if (t->isa_oopptr()) {
3217         n->subsume_by(ConNode::make(t->make_narrowoop()), this);
3218       } else if (t->isa_klassptr()) {
3219         n->subsume_by(ConNode::make(t->make_narrowklass()), this);
3220       }
3221     }
3222     if (in1->outcnt() == 0) {
3223       in1->disconnect_inputs(NULL, this);
3224     }
3225     break;
3226   }
3227 
3228   case Op_Proj: {
3229     if (OptimizeStringConcat) {
3230       ProjNode* p = n->as_Proj();
3231       if (p->_is_io_use) {
3232         // Separate projections were used for the exception path which
3233         // are normally removed by a late inline.  If it wasn't inlined
3234         // then they will hang around and should just be replaced with
3235         // the original one.
3236         Node* proj = NULL;
3237         // Replace with just one
3238         for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
3239           Node *use = i.get();
3240           if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
3241             proj = use;
3242             break;
3243           }
3244         }
3245         assert(proj != NULL, "must be found");
3246         p->subsume_by(proj, this);
3247       }
3248     }
3249     break;
3250   }
3251 
3252   case Op_Phi:
3253     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
3254       // The EncodeP optimization may create Phi with the same edges
3255       // for all paths. It is not handled well by Register Allocator.
3256       Node* unique_in = n->in(1);
3257       assert(unique_in != NULL, "");
3258       uint cnt = n->req();
3259       for (uint i = 2; i < cnt; i++) {
3260         Node* m = n->in(i);
3261         assert(m != NULL, "");
3262         if (unique_in != m)
3263           unique_in = NULL;
3264       }
3265       if (unique_in != NULL) {
3266         n->subsume_by(unique_in, this);
3267       }
3268     }
3269     break;
3270 
3271 #endif
3272 
3273 #ifdef ASSERT
3274   case Op_CastII:
3275     // Verify that all range check dependent CastII nodes were removed.
3276     if (n->isa_CastII()->has_range_check()) {
3277       n->dump(3);
3278       assert(false, "Range check dependent CastII node was not removed");
3279     }
3280     break;
3281 #endif
3282 
3283   case Op_ModI:
3284     if (UseDivMod) {
3285       // Check if a%b and a/b both exist
3286       Node* d = n->find_similar(Op_DivI);
3287       if (d) {
3288         // Replace them with a fused divmod if supported
3289         if (Matcher::has_match_rule(Op_DivModI)) {
3290           DivModINode* divmod = DivModINode::make(n);
3291           d->subsume_by(divmod->div_proj(), this);
3292           n->subsume_by(divmod->mod_proj(), this);
3293         } else {
3294           // replace a%b with a-((a/b)*b)
3295           Node* mult = new MulINode(d, d->in(2));
3296           Node* sub  = new SubINode(d->in(1), mult);
3297           n->subsume_by(sub, this);
3298         }
3299       }
3300     }
3301     break;
3302 
3303   case Op_ModL:
3304     if (UseDivMod) {
3305       // Check if a%b and a/b both exist
3306       Node* d = n->find_similar(Op_DivL);
3307       if (d) {
3308         // Replace them with a fused divmod if supported
3309         if (Matcher::has_match_rule(Op_DivModL)) {
3310           DivModLNode* divmod = DivModLNode::make(n);
3311           d->subsume_by(divmod->div_proj(), this);
3312           n->subsume_by(divmod->mod_proj(), this);
3313         } else {
3314           // replace a%b with a-((a/b)*b)
3315           Node* mult = new MulLNode(d, d->in(2));
3316           Node* sub  = new SubLNode(d->in(1), mult);
3317           n->subsume_by(sub, this);
3318         }
3319       }
3320     }
3321     break;
3322 
3323   case Op_LoadVector:
3324   case Op_StoreVector:
3325     break;
3326 
3327   case Op_AddReductionVI:
3328   case Op_AddReductionVL:
3329   case Op_AddReductionVF:
3330   case Op_AddReductionVD:
3331   case Op_MulReductionVI:
3332   case Op_MulReductionVL:
3333   case Op_MulReductionVF:
3334   case Op_MulReductionVD:
3335     break;
3336 
3337   case Op_PackB:
3338   case Op_PackS:
3339   case Op_PackI:
3340   case Op_PackF:
3341   case Op_PackL:
3342   case Op_PackD:
3343     if (n->req()-1 > 2) {
3344       // Replace many operand PackNodes with a binary tree for matching
3345       PackNode* p = (PackNode*) n;
3346       Node* btp = p->binary_tree_pack(1, n->req());
3347       n->subsume_by(btp, this);
3348     }
3349     break;
3350   case Op_Loop:
3351   case Op_CountedLoop:
3352   case Op_OuterStripMinedLoop:
3353     if (n->as_Loop()->is_inner_loop()) {
3354       frc.inc_inner_loop_count();
3355     }
3356     n->as_Loop()->verify_strip_mined(0);
3357     break;
3358   case Op_LShiftI:
3359   case Op_RShiftI:
3360   case Op_URShiftI:
3361   case Op_LShiftL:
3362   case Op_RShiftL:
3363   case Op_URShiftL:
3364     if (Matcher::need_masked_shift_count) {
3365       // The cpu's shift instructions don't restrict the count to the
3366       // lower 5/6 bits. We need to do the masking ourselves.
3367       Node* in2 = n->in(2);
3368       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
3369       const TypeInt* t = in2->find_int_type();
3370       if (t != NULL && t->is_con()) {
3371         juint shift = t->get_con();
3372         if (shift > mask) { // Unsigned cmp
3373           n->set_req(2, ConNode::make(TypeInt::make(shift & mask)));
3374         }
3375       } else {
3376         if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
3377           Node* shift = new AndINode(in2, ConNode::make(TypeInt::make(mask)));
3378           n->set_req(2, shift);
3379         }
3380       }
3381       if (in2->outcnt() == 0) { // Remove dead node
3382         in2->disconnect_inputs(NULL, this);
3383       }
3384     }
3385     break;
3386   case Op_MemBarStoreStore:
3387   case Op_MemBarRelease:
3388     // Break the link with AllocateNode: it is no longer useful and
3389     // confuses register allocation.
3390     if (n->req() > MemBarNode::Precedent) {
3391       n->set_req(MemBarNode::Precedent, top());
3392     }
3393     break;
3394   case Op_MemBarAcquire: {
3395     if (n->as_MemBar()->trailing_load() && n->req() > MemBarNode::Precedent) {
3396       // At parse time, the trailing MemBarAcquire for a volatile load
3397       // is created with an edge to the load. After optimizations,
3398       // that input may be a chain of Phis. If those phis have no
3399       // other use, then the MemBarAcquire keeps them alive and
3400       // register allocation can be confused.
3401       ResourceMark rm;
3402       Unique_Node_List wq;
3403       wq.push(n->in(MemBarNode::Precedent));
3404       n->set_req(MemBarNode::Precedent, top());
3405       while (wq.size() > 0) {
3406         Node* m = wq.pop();
3407         if (m->outcnt() == 0) {
3408           for (uint j = 0; j < m->req(); j++) {
3409             Node* in = m->in(j);
3410             if (in != NULL) {
3411               wq.push(in);
3412             }
3413           }
3414           m->disconnect_inputs(NULL, this);
3415         }
3416       }
3417     }
3418     break;
3419   }
3420 #if INCLUDE_SHENANDOAHGC
3421   case Op_ShenandoahCompareAndSwapP:
3422   case Op_ShenandoahCompareAndSwapN:
3423   case Op_ShenandoahWeakCompareAndSwapN:
3424   case Op_ShenandoahWeakCompareAndSwapP:
3425   case Op_ShenandoahCompareAndExchangeP:
3426   case Op_ShenandoahCompareAndExchangeN:
3427 #ifdef ASSERT
3428     if( VerifyOptoOopOffsets ) {
3429       MemNode* mem  = n->as_Mem();
3430       // Check to see if address types have grounded out somehow.
3431       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
3432       ciInstanceKlass *k = tp->klass()->as_instance_klass();
3433       bool oop_offset_is_sane = k->contains_field_offset(tp->offset());
3434       assert( !tp || oop_offset_is_sane, "" );
3435     }
3436 #endif
3437      break;
3438   case Op_ShenandoahLoadReferenceBarrier:
3439     assert(false, "should have been expanded already");
3440     break;
3441 #endif
3442   case Op_RangeCheck: {
3443     RangeCheckNode* rc = n->as_RangeCheck();
3444     Node* iff = new IfNode(rc->in(0), rc->in(1), rc->_prob, rc->_fcnt);
3445     n->subsume_by(iff, this);
3446     frc._tests.push(iff);
3447     break;
3448   }
3449   case Op_ConvI2L: {
3450     if (!Matcher::convi2l_type_required) {
3451       // Code generation on some platforms doesn't need accurate
3452       // ConvI2L types. Widening the type can help remove redundant
3453       // address computations.
3454       n->as_Type()->set_type(TypeLong::INT);
3455       ResourceMark rm;
3456       Node_List wq;
3457       wq.push(n);
3458       for (uint next = 0; next < wq.size(); next++) {
3459         Node *m = wq.at(next);
3460 
3461         for(;;) {
3462           // Loop over all nodes with identical inputs edges as m
3463           Node* k = m->find_similar(m->Opcode());
3464           if (k == NULL) {
3465             break;
3466           }
3467           // Push their uses so we get a chance to remove node made
3468           // redundant
3469           for (DUIterator_Fast imax, i = k->fast_outs(imax); i < imax; i++) {
3470             Node* u = k->fast_out(i);
3471             assert(!wq.contains(u), "shouldn't process one node several times");
3472             if (u->Opcode() == Op_LShiftL ||
3473                 u->Opcode() == Op_AddL ||
3474                 u->Opcode() == Op_SubL ||
3475                 u->Opcode() == Op_AddP) {
3476               wq.push(u);
3477             }
3478           }
3479           // Replace all nodes with identical edges as m with m
3480           k->subsume_by(m, this);
3481         }
3482       }
3483     }
3484     break;
3485   }
3486   case Op_CmpUL: {
3487     if (!Matcher::has_match_rule(Op_CmpUL)) {
3488       // No support for unsigned long comparisons
3489       ConINode* sign_pos = new ConINode(TypeInt::make(BitsPerLong - 1));
3490       Node* sign_bit_mask = new RShiftLNode(n->in(1), sign_pos);
3491       Node* orl = new OrLNode(n->in(1), sign_bit_mask);
3492       ConLNode* remove_sign_mask = new ConLNode(TypeLong::make(max_jlong));
3493       Node* andl = new AndLNode(orl, remove_sign_mask);
3494       Node* cmp = new CmpLNode(andl, n->in(2));
3495       n->subsume_by(cmp, this);
3496     }
3497     break;
3498   }
3499   default:
3500     assert( !n->is_Call(), "" );
3501     assert( !n->is_Mem(), "" );
3502     assert( nop != Op_ProfileBoolean, "should be eliminated during IGVN");
3503     break;
3504   }
3505 
3506   // Collect CFG split points
3507   if (n->is_MultiBranch() && !n->is_RangeCheck()) {
3508     frc._tests.push(n);
3509   }
3510 }
3511 
3512 //------------------------------final_graph_reshaping_walk---------------------
3513 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
3514 // requires that the walk visits a node's inputs before visiting the node.
3515 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
3516   ResourceArea *area = Thread::current()->resource_area();
3517   Unique_Node_List sfpt(area);
3518 
3519   frc._visited.set(root->_idx); // first, mark node as visited
3520   uint cnt = root->req();
3521   Node *n = root;
3522   uint  i = 0;
3523   while (true) {
3524     if (i < cnt) {
3525       // Place all non-visited non-null inputs onto stack
3526       Node* m = n->in(i);
3527       ++i;
3528       if (m != NULL && !frc._visited.test_set(m->_idx)) {
3529         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL) {
3530           // compute worst case interpreter size in case of a deoptimization
3531           update_interpreter_frame_size(m->as_SafePoint()->jvms()->interpreter_frame_size());
3532 
3533           sfpt.push(m);
3534         }
3535         cnt = m->req();
3536         nstack.push(n, i); // put on stack parent and next input's index
3537         n = m;
3538         i = 0;
3539       }
3540     } else {
3541       // Now do post-visit work
3542       final_graph_reshaping_impl( n, frc );
3543       if (nstack.is_empty())
3544         break;             // finished
3545       n = nstack.node();   // Get node from stack
3546       cnt = n->req();
3547       i = nstack.index();
3548       nstack.pop();        // Shift to the next node on stack
3549     }
3550   }
3551 
3552   // Skip next transformation if compressed oops are not used.
3553   if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
3554       (!UseCompressedOops && !UseCompressedClassPointers))
3555     return;
3556 
3557   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
3558   // It could be done for an uncommon traps or any safepoints/calls
3559   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
3560   while (sfpt.size() > 0) {
3561     n = sfpt.pop();
3562     JVMState *jvms = n->as_SafePoint()->jvms();
3563     assert(jvms != NULL, "sanity");
3564     int start = jvms->debug_start();
3565     int end   = n->req();
3566     bool is_uncommon = (n->is_CallStaticJava() &&
3567                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
3568     for (int j = start; j < end; j++) {
3569       Node* in = n->in(j);
3570       if (in->is_DecodeNarrowPtr()) {
3571         bool safe_to_skip = true;
3572         if (!is_uncommon ) {
3573           // Is it safe to skip?
3574           for (uint i = 0; i < in->outcnt(); i++) {
3575             Node* u = in->raw_out(i);
3576             if (!u->is_SafePoint() ||
3577                 (u->is_Call() && u->as_Call()->has_non_debug_use(n))) {
3578               safe_to_skip = false;
3579             }
3580           }
3581         }
3582         if (safe_to_skip) {
3583           n->set_req(j, in->in(1));
3584         }
3585         if (in->outcnt() == 0) {
3586           in->disconnect_inputs(NULL, this);
3587         }
3588       }
3589     }
3590   }
3591 }
3592 
3593 //------------------------------final_graph_reshaping--------------------------
3594 // Final Graph Reshaping.
3595 //
3596 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
3597 //     and not commoned up and forced early.  Must come after regular
3598 //     optimizations to avoid GVN undoing the cloning.  Clone constant
3599 //     inputs to Loop Phis; these will be split by the allocator anyways.
3600 //     Remove Opaque nodes.
3601 // (2) Move last-uses by commutative operations to the left input to encourage
3602 //     Intel update-in-place two-address operations and better register usage
3603 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
3604 //     calls canonicalizing them back.
3605 // (3) Count the number of double-precision FP ops, single-precision FP ops
3606 //     and call sites.  On Intel, we can get correct rounding either by
3607 //     forcing singles to memory (requires extra stores and loads after each
3608 //     FP bytecode) or we can set a rounding mode bit (requires setting and
3609 //     clearing the mode bit around call sites).  The mode bit is only used
3610 //     if the relative frequency of single FP ops to calls is low enough.
3611 //     This is a key transform for SPEC mpeg_audio.
3612 // (4) Detect infinite loops; blobs of code reachable from above but not
3613 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
3614 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
3615 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
3616 //     Detection is by looking for IfNodes where only 1 projection is
3617 //     reachable from below or CatchNodes missing some targets.
3618 // (5) Assert for insane oop offsets in debug mode.
3619 
3620 bool Compile::final_graph_reshaping() {
3621   // an infinite loop may have been eliminated by the optimizer,
3622   // in which case the graph will be empty.
3623   if (root()->req() == 1) {
3624     record_method_not_compilable("trivial infinite loop");
3625     return true;
3626   }
3627 
3628   // Expensive nodes have their control input set to prevent the GVN
3629   // from freely commoning them. There's no GVN beyond this point so
3630   // no need to keep the control input. We want the expensive nodes to
3631   // be freely moved to the least frequent code path by gcm.
3632   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
3633   for (int i = 0; i < expensive_count(); i++) {
3634     _expensive_nodes->at(i)->set_req(0, NULL);
3635   }
3636 
3637   Final_Reshape_Counts frc;
3638 
3639   // Visit everybody reachable!
3640   // Allocate stack of size C->live_nodes()/2 to avoid frequent realloc
3641   Node_Stack nstack(live_nodes() >> 1);
3642   final_graph_reshaping_walk(nstack, root(), frc);
3643 
3644   // Check for unreachable (from below) code (i.e., infinite loops).
3645   for( uint i = 0; i < frc._tests.size(); i++ ) {
3646     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
3647     // Get number of CFG targets.
3648     // Note that PCTables include exception targets after calls.
3649     uint required_outcnt = n->required_outcnt();
3650     if (n->outcnt() != required_outcnt) {
3651       // Check for a few special cases.  Rethrow Nodes never take the
3652       // 'fall-thru' path, so expected kids is 1 less.
3653       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
3654         if (n->in(0)->in(0)->is_Call()) {
3655           CallNode *call = n->in(0)->in(0)->as_Call();
3656           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
3657             required_outcnt--;      // Rethrow always has 1 less kid
3658           } else if (call->req() > TypeFunc::Parms &&
3659                      call->is_CallDynamicJava()) {
3660             // Check for null receiver. In such case, the optimizer has
3661             // detected that the virtual call will always result in a null
3662             // pointer exception. The fall-through projection of this CatchNode
3663             // will not be populated.
3664             Node *arg0 = call->in(TypeFunc::Parms);
3665             if (arg0->is_Type() &&
3666                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
3667               required_outcnt--;
3668             }
3669           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
3670                      call->req() > TypeFunc::Parms+1 &&
3671                      call->is_CallStaticJava()) {
3672             // Check for negative array length. In such case, the optimizer has
3673             // detected that the allocation attempt will always result in an
3674             // exception. There is no fall-through projection of this CatchNode .
3675             Node *arg1 = call->in(TypeFunc::Parms+1);
3676             if (arg1->is_Type() &&
3677                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
3678               required_outcnt--;
3679             }
3680           }
3681         }
3682       }
3683       // Recheck with a better notion of 'required_outcnt'
3684       if (n->outcnt() != required_outcnt) {
3685         record_method_not_compilable("malformed control flow");
3686         return true;            // Not all targets reachable!
3687       }
3688     }
3689     // Check that I actually visited all kids.  Unreached kids
3690     // must be infinite loops.
3691     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
3692       if (!frc._visited.test(n->fast_out(j)->_idx)) {
3693         record_method_not_compilable("infinite loop");
3694         return true;            // Found unvisited kid; must be unreach
3695       }
3696 
3697     // Here so verification code in final_graph_reshaping_walk()
3698     // always see an OuterStripMinedLoopEnd
3699     if (n->is_OuterStripMinedLoopEnd()) {
3700       IfNode* init_iff = n->as_If();
3701       Node* iff = new IfNode(init_iff->in(0), init_iff->in(1), init_iff->_prob, init_iff->_fcnt);
3702       n->subsume_by(iff, this);
3703     }
3704   }
3705 
3706   // If original bytecodes contained a mixture of floats and doubles
3707   // check if the optimizer has made it homogenous, item (3).
3708   if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
3709       frc.get_float_count() > 32 &&
3710       frc.get_double_count() == 0 &&
3711       (10 * frc.get_call_count() < frc.get_float_count()) ) {
3712     set_24_bit_selection_and_mode( false,  true );
3713   }
3714 
3715   set_java_calls(frc.get_java_call_count());
3716   set_inner_loops(frc.get_inner_loop_count());
3717 
3718   // No infinite loops, no reason to bail out.
3719   return false;
3720 }
3721 
3722 //-----------------------------too_many_traps----------------------------------
3723 // Report if there are too many traps at the current method and bci.
3724 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
3725 bool Compile::too_many_traps(ciMethod* method,
3726                              int bci,
3727                              Deoptimization::DeoptReason reason) {
3728   ciMethodData* md = method->method_data();
3729   if (md->is_empty()) {
3730     // Assume the trap has not occurred, or that it occurred only
3731     // because of a transient condition during start-up in the interpreter.
3732     return false;
3733   }
3734   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3735   if (md->has_trap_at(bci, m, reason) != 0) {
3736     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
3737     // Also, if there are multiple reasons, or if there is no per-BCI record,
3738     // assume the worst.
3739     if (log())
3740       log()->elem("observe trap='%s' count='%d'",
3741                   Deoptimization::trap_reason_name(reason),
3742                   md->trap_count(reason));
3743     return true;
3744   } else {
3745     // Ignore method/bci and see if there have been too many globally.
3746     return too_many_traps(reason, md);
3747   }
3748 }
3749 
3750 // Less-accurate variant which does not require a method and bci.
3751 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
3752                              ciMethodData* logmd) {
3753   if (trap_count(reason) >= Deoptimization::per_method_trap_limit(reason)) {
3754     // Too many traps globally.
3755     // Note that we use cumulative trap_count, not just md->trap_count.
3756     if (log()) {
3757       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
3758       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
3759                   Deoptimization::trap_reason_name(reason),
3760                   mcount, trap_count(reason));
3761     }
3762     return true;
3763   } else {
3764     // The coast is clear.
3765     return false;
3766   }
3767 }
3768 
3769 //--------------------------too_many_recompiles--------------------------------
3770 // Report if there are too many recompiles at the current method and bci.
3771 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
3772 // Is not eager to return true, since this will cause the compiler to use
3773 // Action_none for a trap point, to avoid too many recompilations.
3774 bool Compile::too_many_recompiles(ciMethod* method,
3775                                   int bci,
3776                                   Deoptimization::DeoptReason reason) {
3777   ciMethodData* md = method->method_data();
3778   if (md->is_empty()) {
3779     // Assume the trap has not occurred, or that it occurred only
3780     // because of a transient condition during start-up in the interpreter.
3781     return false;
3782   }
3783   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
3784   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
3785   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
3786   Deoptimization::DeoptReason per_bc_reason
3787     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
3788   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3789   if ((per_bc_reason == Deoptimization::Reason_none
3790        || md->has_trap_at(bci, m, reason) != 0)
3791       // The trap frequency measure we care about is the recompile count:
3792       && md->trap_recompiled_at(bci, m)
3793       && md->overflow_recompile_count() >= bc_cutoff) {
3794     // Do not emit a trap here if it has already caused recompilations.
3795     // Also, if there are multiple reasons, or if there is no per-BCI record,
3796     // assume the worst.
3797     if (log())
3798       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
3799                   Deoptimization::trap_reason_name(reason),
3800                   md->trap_count(reason),
3801                   md->overflow_recompile_count());
3802     return true;
3803   } else if (trap_count(reason) != 0
3804              && decompile_count() >= m_cutoff) {
3805     // Too many recompiles globally, and we have seen this sort of trap.
3806     // Use cumulative decompile_count, not just md->decompile_count.
3807     if (log())
3808       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
3809                   Deoptimization::trap_reason_name(reason),
3810                   md->trap_count(reason), trap_count(reason),
3811                   md->decompile_count(), decompile_count());
3812     return true;
3813   } else {
3814     // The coast is clear.
3815     return false;
3816   }
3817 }
3818 
3819 // Compute when not to trap. Used by matching trap based nodes and
3820 // NullCheck optimization.
3821 void Compile::set_allowed_deopt_reasons() {
3822   _allowed_reasons = 0;
3823   if (is_method_compilation()) {
3824     for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
3825       assert(rs < BitsPerInt, "recode bit map");
3826       if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
3827         _allowed_reasons |= nth_bit(rs);
3828       }
3829     }
3830   }
3831 }
3832 
3833 bool Compile::is_compiling_clinit_for(ciKlass* k) {
3834   ciMethod* root = method(); // the root method of compilation
3835   return root->is_static_initializer() && root->holder() == k; // access in the context of clinit
3836 }
3837 
3838 #ifndef PRODUCT
3839 //------------------------------verify_graph_edges---------------------------
3840 // Walk the Graph and verify that there is a one-to-one correspondence
3841 // between Use-Def edges and Def-Use edges in the graph.
3842 void Compile::verify_graph_edges(bool no_dead_code) {
3843   if (VerifyGraphEdges) {
3844     ResourceArea *area = Thread::current()->resource_area();
3845     Unique_Node_List visited(area);
3846     // Call recursive graph walk to check edges
3847     _root->verify_edges(visited);
3848     if (no_dead_code) {
3849       // Now make sure that no visited node is used by an unvisited node.
3850       bool dead_nodes = false;
3851       Unique_Node_List checked(area);
3852       while (visited.size() > 0) {
3853         Node* n = visited.pop();
3854         checked.push(n);
3855         for (uint i = 0; i < n->outcnt(); i++) {
3856           Node* use = n->raw_out(i);
3857           if (checked.member(use))  continue;  // already checked
3858           if (visited.member(use))  continue;  // already in the graph
3859           if (use->is_Con())        continue;  // a dead ConNode is OK
3860           // At this point, we have found a dead node which is DU-reachable.
3861           if (!dead_nodes) {
3862             tty->print_cr("*** Dead nodes reachable via DU edges:");
3863             dead_nodes = true;
3864           }
3865           use->dump(2);
3866           tty->print_cr("---");
3867           checked.push(use);  // No repeats; pretend it is now checked.
3868         }
3869       }
3870       assert(!dead_nodes, "using nodes must be reachable from root");
3871     }
3872   }
3873 }
3874 
3875 // Verify GC barriers consistency
3876 // Currently supported:
3877 // - G1 pre-barriers (see GraphKit::g1_write_barrier_pre())
3878 void Compile::verify_barriers() {
3879 #if INCLUDE_G1GC || INCLUDE_SHENANDOAHGC
3880   if (UseG1GC || UseShenandoahGC) {
3881     // Verify G1 pre-barriers
3882 
3883 #if INCLUDE_G1GC && INCLUDE_SHENANDOAHGC
3884     const int marking_offset = in_bytes(UseG1GC ? G1ThreadLocalData::satb_mark_queue_active_offset()
3885                                                 : ShenandoahThreadLocalData::satb_mark_queue_active_offset());
3886 #elif INCLUDE_G1GC
3887     const int marking_offset = in_bytes(G1ThreadLocalData::satb_mark_queue_active_offset());
3888 #else
3889     const int marking_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset());
3890 #endif
3891 
3892     ResourceArea *area = Thread::current()->resource_area();
3893     Unique_Node_List visited(area);
3894     Node_List worklist(area);
3895     // We're going to walk control flow backwards starting from the Root
3896     worklist.push(_root);
3897     while (worklist.size() > 0) {
3898       Node* x = worklist.pop();
3899       if (x == NULL || x == top()) continue;
3900       if (visited.member(x)) {
3901         continue;
3902       } else {
3903         visited.push(x);
3904       }
3905 
3906       if (x->is_Region()) {
3907         for (uint i = 1; i < x->req(); i++) {
3908           worklist.push(x->in(i));
3909         }
3910       } else {
3911         worklist.push(x->in(0));
3912         // We are looking for the pattern:
3913         //                            /->ThreadLocal
3914         // If->Bool->CmpI->LoadB->AddP->ConL(marking_offset)
3915         //              \->ConI(0)
3916         // We want to verify that the If and the LoadB have the same control
3917         // See GraphKit::g1_write_barrier_pre()
3918         if (x->is_If()) {
3919           IfNode *iff = x->as_If();
3920           if (iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) {
3921             CmpNode *cmp = iff->in(1)->in(1)->as_Cmp();
3922             if (cmp->Opcode() == Op_CmpI && cmp->in(2)->is_Con() && cmp->in(2)->bottom_type()->is_int()->get_con() == 0
3923                 && cmp->in(1)->is_Load()) {
3924               LoadNode* load = cmp->in(1)->as_Load();
3925               if (load->Opcode() == Op_LoadB && load->in(2)->is_AddP() && load->in(2)->in(2)->Opcode() == Op_ThreadLocal
3926                   && load->in(2)->in(3)->is_Con()
3927                   && load->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == marking_offset) {
3928 
3929                 Node* if_ctrl = iff->in(0);
3930                 Node* load_ctrl = load->in(0);
3931 
3932                 if (if_ctrl != load_ctrl) {
3933                   // Skip possible CProj->NeverBranch in infinite loops
3934                   if ((if_ctrl->is_Proj() && if_ctrl->Opcode() == Op_CProj)
3935                       && (if_ctrl->in(0)->is_MultiBranch() && if_ctrl->in(0)->Opcode() == Op_NeverBranch)) {
3936                     if_ctrl = if_ctrl->in(0)->in(0);
3937                   }
3938                 }
3939                 assert(load_ctrl != NULL && if_ctrl == load_ctrl, "controls must match");
3940               }
3941             }
3942           }
3943         }
3944       }
3945     }
3946   }
3947 #endif
3948 }
3949 
3950 #endif
3951 
3952 // The Compile object keeps track of failure reasons separately from the ciEnv.
3953 // This is required because there is not quite a 1-1 relation between the
3954 // ciEnv and its compilation task and the Compile object.  Note that one
3955 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
3956 // to backtrack and retry without subsuming loads.  Other than this backtracking
3957 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
3958 // by the logic in C2Compiler.
3959 void Compile::record_failure(const char* reason) {
3960   if (log() != NULL) {
3961     log()->elem("failure reason='%s' phase='compile'", reason);
3962   }
3963   if (_failure_reason == NULL) {
3964     // Record the first failure reason.
3965     _failure_reason = reason;
3966   }
3967 
3968   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
3969     C->print_method(PHASE_FAILURE);
3970   }
3971   _root = NULL;  // flush the graph, too
3972 }
3973 
3974 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator)
3975   : TraceTime(name, accumulator, CITime, CITimeVerbose),
3976     _phase_name(name), _dolog(CITimeVerbose)
3977 {
3978   if (_dolog) {
3979     C = Compile::current();
3980     _log = C->log();
3981   } else {
3982     C = NULL;
3983     _log = NULL;
3984   }
3985   if (_log != NULL) {
3986     _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3987     _log->stamp();
3988     _log->end_head();
3989   }
3990 }
3991 
3992 Compile::TracePhase::~TracePhase() {
3993 
3994   C = Compile::current();
3995   if (_dolog) {
3996     _log = C->log();
3997   } else {
3998     _log = NULL;
3999   }
4000 
4001 #ifdef ASSERT
4002   if (PrintIdealNodeCount) {
4003     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
4004                   _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
4005   }
4006 
4007   if (VerifyIdealNodeCount) {
4008     Compile::current()->print_missing_nodes();
4009   }
4010 #endif
4011 
4012   if (_log != NULL) {
4013     _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
4014   }
4015 }
4016 
4017 //=============================================================================
4018 // Two Constant's are equal when the type and the value are equal.
4019 bool Compile::Constant::operator==(const Constant& other) {
4020   if (type()          != other.type()         )  return false;
4021   if (can_be_reused() != other.can_be_reused())  return false;
4022   // For floating point values we compare the bit pattern.
4023   switch (type()) {
4024   case T_INT:
4025   case T_FLOAT:   return (_v._value.i == other._v._value.i);
4026   case T_LONG:
4027   case T_DOUBLE:  return (_v._value.j == other._v._value.j);
4028   case T_OBJECT:
4029   case T_ADDRESS: return (_v._value.l == other._v._value.l);
4030   case T_VOID:    return (_v._value.l == other._v._value.l);  // jump-table entries
4031   case T_METADATA: return (_v._metadata == other._v._metadata);
4032   default: ShouldNotReachHere(); return false;
4033   }
4034 }
4035 
4036 static int type_to_size_in_bytes(BasicType t) {
4037   switch (t) {
4038   case T_INT:     return sizeof(jint   );
4039   case T_LONG:    return sizeof(jlong  );
4040   case T_FLOAT:   return sizeof(jfloat );
4041   case T_DOUBLE:  return sizeof(jdouble);
4042   case T_METADATA: return sizeof(Metadata*);
4043     // We use T_VOID as marker for jump-table entries (labels) which
4044     // need an internal word relocation.
4045   case T_VOID:
4046   case T_ADDRESS:
4047   case T_OBJECT:  return sizeof(jobject);
4048   default:
4049     ShouldNotReachHere();
4050     return -1;
4051   }
4052 }
4053 
4054 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
4055   // sort descending
4056   if (a->freq() > b->freq())  return -1;
4057   if (a->freq() < b->freq())  return  1;
4058   return 0;
4059 }
4060 
4061 void Compile::ConstantTable::calculate_offsets_and_size() {
4062   // First, sort the array by frequencies.
4063   _constants.sort(qsort_comparator);
4064 
4065 #ifdef ASSERT
4066   // Make sure all jump-table entries were sorted to the end of the
4067   // array (they have a negative frequency).
4068   bool found_void = false;
4069   for (int i = 0; i < _constants.length(); i++) {
4070     Constant con = _constants.at(i);
4071     if (con.type() == T_VOID)
4072       found_void = true;  // jump-tables
4073     else
4074       assert(!found_void, "wrong sorting");
4075   }
4076 #endif
4077 
4078   int offset = 0;
4079   for (int i = 0; i < _constants.length(); i++) {
4080     Constant* con = _constants.adr_at(i);
4081 
4082     // Align offset for type.
4083     int typesize = type_to_size_in_bytes(con->type());
4084     offset = align_up(offset, typesize);
4085     con->set_offset(offset);   // set constant's offset
4086 
4087     if (con->type() == T_VOID) {
4088       MachConstantNode* n = (MachConstantNode*) con->get_jobject();
4089       offset = offset + typesize * n->outcnt();  // expand jump-table
4090     } else {
4091       offset = offset + typesize;
4092     }
4093   }
4094 
4095   // Align size up to the next section start (which is insts; see
4096   // CodeBuffer::align_at_start).
4097   assert(_size == -1, "already set?");
4098   _size = align_up(offset, (int)CodeEntryAlignment);
4099 }
4100 
4101 void Compile::ConstantTable::emit(CodeBuffer& cb) {
4102   MacroAssembler _masm(&cb);
4103   for (int i = 0; i < _constants.length(); i++) {
4104     Constant con = _constants.at(i);
4105     address constant_addr = NULL;
4106     switch (con.type()) {
4107     case T_INT:    constant_addr = _masm.int_constant(   con.get_jint()   ); break;
4108     case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
4109     case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
4110     case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
4111     case T_OBJECT: {
4112       jobject obj = con.get_jobject();
4113       int oop_index = _masm.oop_recorder()->find_index(obj);
4114       constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
4115       break;
4116     }
4117     case T_ADDRESS: {
4118       address addr = (address) con.get_jobject();
4119       constant_addr = _masm.address_constant(addr);
4120       break;
4121     }
4122     // We use T_VOID as marker for jump-table entries (labels) which
4123     // need an internal word relocation.
4124     case T_VOID: {
4125       MachConstantNode* n = (MachConstantNode*) con.get_jobject();
4126       // Fill the jump-table with a dummy word.  The real value is
4127       // filled in later in fill_jump_table.
4128       address dummy = (address) n;
4129       constant_addr = _masm.address_constant(dummy);
4130       // Expand jump-table
4131       for (uint i = 1; i < n->outcnt(); i++) {
4132         address temp_addr = _masm.address_constant(dummy + i);
4133         assert(temp_addr, "consts section too small");
4134       }
4135       break;
4136     }
4137     case T_METADATA: {
4138       Metadata* obj = con.get_metadata();
4139       int metadata_index = _masm.oop_recorder()->find_index(obj);
4140       constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
4141       break;
4142     }
4143     default: ShouldNotReachHere();
4144     }
4145     assert(constant_addr, "consts section too small");
4146     assert((constant_addr - _masm.code()->consts()->start()) == con.offset(),
4147             "must be: %d == %d", (int) (constant_addr - _masm.code()->consts()->start()), (int)(con.offset()));
4148   }
4149 }
4150 
4151 int Compile::ConstantTable::find_offset(Constant& con) const {
4152   int idx = _constants.find(con);
4153   guarantee(idx != -1, "constant must be in constant table");
4154   int offset = _constants.at(idx).offset();
4155   guarantee(offset != -1, "constant table not emitted yet?");
4156   return offset;
4157 }
4158 
4159 void Compile::ConstantTable::add(Constant& con) {
4160   if (con.can_be_reused()) {
4161     int idx = _constants.find(con);
4162     if (idx != -1 && _constants.at(idx).can_be_reused()) {
4163       _constants.adr_at(idx)->inc_freq(con.freq());  // increase the frequency by the current value
4164       return;
4165     }
4166   }
4167   (void) _constants.append(con);
4168 }
4169 
4170 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
4171   Block* b = Compile::current()->cfg()->get_block_for_node(n);
4172   Constant con(type, value, b->_freq);
4173   add(con);
4174   return con;
4175 }
4176 
4177 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
4178   Constant con(metadata);
4179   add(con);
4180   return con;
4181 }
4182 
4183 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
4184   jvalue value;
4185   BasicType type = oper->type()->basic_type();
4186   switch (type) {
4187   case T_LONG:    value.j = oper->constantL(); break;
4188   case T_FLOAT:   value.f = oper->constantF(); break;
4189   case T_DOUBLE:  value.d = oper->constantD(); break;
4190   case T_OBJECT:
4191   case T_ADDRESS: value.l = (jobject) oper->constant(); break;
4192   case T_METADATA: return add((Metadata*)oper->constant()); break;
4193   default: guarantee(false, "unhandled type: %s", type2name(type));
4194   }
4195   return add(n, type, value);
4196 }
4197 
4198 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
4199   jvalue value;
4200   // We can use the node pointer here to identify the right jump-table
4201   // as this method is called from Compile::Fill_buffer right before
4202   // the MachNodes are emitted and the jump-table is filled (means the
4203   // MachNode pointers do not change anymore).
4204   value.l = (jobject) n;
4205   Constant con(T_VOID, value, next_jump_table_freq(), false);  // Labels of a jump-table cannot be reused.
4206   add(con);
4207   return con;
4208 }
4209 
4210 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
4211   // If called from Compile::scratch_emit_size do nothing.
4212   if (Compile::current()->in_scratch_emit_size())  return;
4213 
4214   assert(labels.is_nonempty(), "must be");
4215   assert((uint) labels.length() == n->outcnt(), "must be equal: %d == %d", labels.length(), n->outcnt());
4216 
4217   // Since MachConstantNode::constant_offset() also contains
4218   // table_base_offset() we need to subtract the table_base_offset()
4219   // to get the plain offset into the constant table.
4220   int offset = n->constant_offset() - table_base_offset();
4221 
4222   MacroAssembler _masm(&cb);
4223   address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
4224 
4225   for (uint i = 0; i < n->outcnt(); i++) {
4226     address* constant_addr = &jump_table_base[i];
4227     assert(*constant_addr == (((address) n) + i), "all jump-table entries must contain adjusted node pointer: " INTPTR_FORMAT " == " INTPTR_FORMAT, p2i(*constant_addr), p2i(((address) n) + i));
4228     *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
4229     cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
4230   }
4231 }
4232 
4233 //----------------------------static_subtype_check-----------------------------
4234 // Shortcut important common cases when superklass is exact:
4235 // (0) superklass is java.lang.Object (can occur in reflective code)
4236 // (1) subklass is already limited to a subtype of superklass => always ok
4237 // (2) subklass does not overlap with superklass => always fail
4238 // (3) superklass has NO subtypes and we can check with a simple compare.
4239 int Compile::static_subtype_check(ciKlass* superk, ciKlass* subk) {
4240   if (StressReflectiveCode) {
4241     return SSC_full_test;       // Let caller generate the general case.
4242   }
4243 
4244   if (superk == env()->Object_klass()) {
4245     return SSC_always_true;     // (0) this test cannot fail
4246   }
4247 
4248   ciType* superelem = superk;
4249   if (superelem->is_array_klass())
4250     superelem = superelem->as_array_klass()->base_element_type();
4251 
4252   if (!subk->is_interface()) {  // cannot trust static interface types yet
4253     if (subk->is_subtype_of(superk)) {
4254       return SSC_always_true;   // (1) false path dead; no dynamic test needed
4255     }
4256     if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
4257         !superk->is_subtype_of(subk)) {
4258       return SSC_always_false;
4259     }
4260   }
4261 
4262   // If casting to an instance klass, it must have no subtypes
4263   if (superk->is_interface()) {
4264     // Cannot trust interfaces yet.
4265     // %%% S.B. superk->nof_implementors() == 1
4266   } else if (superelem->is_instance_klass()) {
4267     ciInstanceKlass* ik = superelem->as_instance_klass();
4268     if (!ik->has_subklass() && !ik->is_interface()) {
4269       if (!ik->is_final()) {
4270         // Add a dependency if there is a chance of a later subclass.
4271         dependencies()->assert_leaf_type(ik);
4272       }
4273       return SSC_easy_test;     // (3) caller can do a simple ptr comparison
4274     }
4275   } else {
4276     // A primitive array type has no subtypes.
4277     return SSC_easy_test;       // (3) caller can do a simple ptr comparison
4278   }
4279 
4280   return SSC_full_test;
4281 }
4282 
4283 Node* Compile::conv_I2X_index(PhaseGVN* phase, Node* idx, const TypeInt* sizetype, Node* ctrl) {
4284 #ifdef _LP64
4285   // The scaled index operand to AddP must be a clean 64-bit value.
4286   // Java allows a 32-bit int to be incremented to a negative
4287   // value, which appears in a 64-bit register as a large
4288   // positive number.  Using that large positive number as an
4289   // operand in pointer arithmetic has bad consequences.
4290   // On the other hand, 32-bit overflow is rare, and the possibility
4291   // can often be excluded, if we annotate the ConvI2L node with
4292   // a type assertion that its value is known to be a small positive
4293   // number.  (The prior range check has ensured this.)
4294   // This assertion is used by ConvI2LNode::Ideal.
4295   int index_max = max_jint - 1;  // array size is max_jint, index is one less
4296   if (sizetype != NULL) index_max = sizetype->_hi - 1;
4297   const TypeInt* iidxtype = TypeInt::make(0, index_max, Type::WidenMax);
4298   idx = constrained_convI2L(phase, idx, iidxtype, ctrl);
4299 #endif
4300   return idx;
4301 }
4302 
4303 // Convert integer value to a narrowed long type dependent on ctrl (for example, a range check)
4304 Node* Compile::constrained_convI2L(PhaseGVN* phase, Node* value, const TypeInt* itype, Node* ctrl) {
4305   if (ctrl != NULL) {
4306     // Express control dependency by a CastII node with a narrow type.
4307     value = new CastIINode(value, itype, false, true /* range check dependency */);
4308     // Make the CastII node dependent on the control input to prevent the narrowed ConvI2L
4309     // node from floating above the range check during loop optimizations. Otherwise, the
4310     // ConvI2L node may be eliminated independently of the range check, causing the data path
4311     // to become TOP while the control path is still there (although it's unreachable).
4312     value->set_req(0, ctrl);
4313     // Save CastII node to remove it after loop optimizations.
4314     phase->C->add_range_check_cast(value);
4315     value = phase->transform(value);
4316   }
4317   const TypeLong* ltype = TypeLong::make(itype->_lo, itype->_hi, itype->_widen);
4318   return phase->transform(new ConvI2LNode(value, ltype));
4319 }
4320 
4321 // The message about the current inlining is accumulated in
4322 // _print_inlining_stream and transfered into the _print_inlining_list
4323 // once we know whether inlining succeeds or not. For regular
4324 // inlining, messages are appended to the buffer pointed by
4325 // _print_inlining_idx in the _print_inlining_list. For late inlining,
4326 // a new buffer is added after _print_inlining_idx in the list. This
4327 // way we can update the inlining message for late inlining call site
4328 // when the inlining is attempted again.
4329 void Compile::print_inlining_init() {
4330   if (print_inlining() || print_intrinsics()) {
4331     _print_inlining_stream = new stringStream();
4332     _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
4333   }
4334 }
4335 
4336 void Compile::print_inlining_reinit() {
4337   if (print_inlining() || print_intrinsics()) {
4338     // Re allocate buffer when we change ResourceMark
4339     _print_inlining_stream = new stringStream();
4340   }
4341 }
4342 
4343 void Compile::print_inlining_reset() {
4344   _print_inlining_stream->reset();
4345 }
4346 
4347 void Compile::print_inlining_commit() {
4348   assert(print_inlining() || print_intrinsics(), "PrintInlining off?");
4349   // Transfer the message from _print_inlining_stream to the current
4350   // _print_inlining_list buffer and clear _print_inlining_stream.
4351   _print_inlining_list->at(_print_inlining_idx).ss()->write(_print_inlining_stream->as_string(), _print_inlining_stream->size());
4352   print_inlining_reset();
4353 }
4354 
4355 void Compile::print_inlining_push() {
4356   // Add new buffer to the _print_inlining_list at current position
4357   _print_inlining_idx++;
4358   _print_inlining_list->insert_before(_print_inlining_idx, PrintInliningBuffer());
4359 }
4360 
4361 Compile::PrintInliningBuffer& Compile::print_inlining_current() {
4362   return _print_inlining_list->at(_print_inlining_idx);
4363 }
4364 
4365 void Compile::print_inlining_update(CallGenerator* cg) {
4366   if (print_inlining() || print_intrinsics()) {
4367     if (!cg->is_late_inline()) {
4368       if (print_inlining_current().cg() != NULL) {
4369         print_inlining_push();
4370       }
4371       print_inlining_commit();
4372     } else {
4373       if (print_inlining_current().cg() != cg &&
4374           (print_inlining_current().cg() != NULL ||
4375            print_inlining_current().ss()->size() != 0)) {
4376         print_inlining_push();
4377       }
4378       print_inlining_commit();
4379       print_inlining_current().set_cg(cg);
4380     }
4381   }
4382 }
4383 
4384 void Compile::print_inlining_move_to(CallGenerator* cg) {
4385   // We resume inlining at a late inlining call site. Locate the
4386   // corresponding inlining buffer so that we can update it.
4387   if (print_inlining()) {
4388     for (int i = 0; i < _print_inlining_list->length(); i++) {
4389       if (_print_inlining_list->adr_at(i)->cg() == cg) {
4390         _print_inlining_idx = i;
4391         return;
4392       }
4393     }
4394     ShouldNotReachHere();
4395   }
4396 }
4397 
4398 void Compile::print_inlining_update_delayed(CallGenerator* cg) {
4399   if (print_inlining()) {
4400     assert(_print_inlining_stream->size() > 0, "missing inlining msg");
4401     assert(print_inlining_current().cg() == cg, "wrong entry");
4402     // replace message with new message
4403     _print_inlining_list->at_put(_print_inlining_idx, PrintInliningBuffer());
4404     print_inlining_commit();
4405     print_inlining_current().set_cg(cg);
4406   }
4407 }
4408 
4409 void Compile::print_inlining_assert_ready() {
4410   assert(!_print_inlining || _print_inlining_stream->size() == 0, "loosing data");
4411 }
4412 
4413 void Compile::process_print_inlining() {
4414   bool do_print_inlining = print_inlining() || print_intrinsics();
4415   if (do_print_inlining || log() != NULL) {
4416     // Print inlining message for candidates that we couldn't inline
4417     // for lack of space
4418     for (int i = 0; i < _late_inlines.length(); i++) {
4419       CallGenerator* cg = _late_inlines.at(i);
4420       if (!cg->is_mh_late_inline()) {
4421         const char* msg = "live nodes > LiveNodeCountInliningCutoff";
4422         if (do_print_inlining) {
4423           cg->print_inlining_late(msg);
4424         }
4425         log_late_inline_failure(cg, msg);
4426       }
4427     }
4428   }
4429   if (do_print_inlining) {
4430     ResourceMark rm;
4431     stringStream ss;
4432     for (int i = 0; i < _print_inlining_list->length(); i++) {
4433       ss.print("%s", _print_inlining_list->adr_at(i)->ss()->as_string());
4434     }
4435     size_t end = ss.size();
4436     _print_inlining_output = NEW_ARENA_ARRAY(comp_arena(), char, end+1);
4437     strncpy(_print_inlining_output, ss.base(), end+1);
4438     _print_inlining_output[end] = 0;
4439   }
4440 }
4441 
4442 void Compile::dump_print_inlining() {
4443   if (_print_inlining_output != NULL) {
4444     tty->print_raw(_print_inlining_output);
4445   }
4446 }
4447 
4448 void Compile::log_late_inline(CallGenerator* cg) {
4449   if (log() != NULL) {
4450     log()->head("late_inline method='%d'  inline_id='" JLONG_FORMAT "'", log()->identify(cg->method()),
4451                 cg->unique_id());
4452     JVMState* p = cg->call_node()->jvms();
4453     while (p != NULL) {
4454       log()->elem("jvms bci='%d' method='%d'", p->bci(), log()->identify(p->method()));
4455       p = p->caller();
4456     }
4457     log()->tail("late_inline");
4458   }
4459 }
4460 
4461 void Compile::log_late_inline_failure(CallGenerator* cg, const char* msg) {
4462   log_late_inline(cg);
4463   if (log() != NULL) {
4464     log()->inline_fail(msg);
4465   }
4466 }
4467 
4468 void Compile::log_inline_id(CallGenerator* cg) {
4469   if (log() != NULL) {
4470     // The LogCompilation tool needs a unique way to identify late
4471     // inline call sites. This id must be unique for this call site in
4472     // this compilation. Try to have it unique across compilations as
4473     // well because it can be convenient when grepping through the log
4474     // file.
4475     // Distinguish OSR compilations from others in case CICountOSR is
4476     // on.
4477     jlong id = ((jlong)unique()) + (((jlong)compile_id()) << 33) + (CICountOSR && is_osr_compilation() ? ((jlong)1) << 32 : 0);
4478     cg->set_unique_id(id);
4479     log()->elem("inline_id id='" JLONG_FORMAT "'", id);
4480   }
4481 }
4482 
4483 void Compile::log_inline_failure(const char* msg) {
4484   if (C->log() != NULL) {
4485     C->log()->inline_fail(msg);
4486   }
4487 }
4488 
4489 
4490 // Dump inlining replay data to the stream.
4491 // Don't change thread state and acquire any locks.
4492 void Compile::dump_inline_data(outputStream* out) {
4493   InlineTree* inl_tree = ilt();
4494   if (inl_tree != NULL) {
4495     out->print(" inline %d", inl_tree->count());
4496     inl_tree->dump_replay_data(out);
4497   }
4498 }
4499 
4500 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
4501   if (n1->Opcode() < n2->Opcode())      return -1;
4502   else if (n1->Opcode() > n2->Opcode()) return 1;
4503 
4504   assert(n1->req() == n2->req(), "can't compare %s nodes: n1->req() = %d, n2->req() = %d", NodeClassNames[n1->Opcode()], n1->req(), n2->req());
4505   for (uint i = 1; i < n1->req(); i++) {
4506     if (n1->in(i) < n2->in(i))      return -1;
4507     else if (n1->in(i) > n2->in(i)) return 1;
4508   }
4509 
4510   return 0;
4511 }
4512 
4513 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
4514   Node* n1 = *n1p;
4515   Node* n2 = *n2p;
4516 
4517   return cmp_expensive_nodes(n1, n2);
4518 }
4519 
4520 void Compile::sort_expensive_nodes() {
4521   if (!expensive_nodes_sorted()) {
4522     _expensive_nodes->sort(cmp_expensive_nodes);
4523   }
4524 }
4525 
4526 bool Compile::expensive_nodes_sorted() const {
4527   for (int i = 1; i < _expensive_nodes->length(); i++) {
4528     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
4529       return false;
4530     }
4531   }
4532   return true;
4533 }
4534 
4535 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
4536   if (_expensive_nodes->length() == 0) {
4537     return false;
4538   }
4539 
4540   assert(OptimizeExpensiveOps, "optimization off?");
4541 
4542   // Take this opportunity to remove dead nodes from the list
4543   int j = 0;
4544   for (int i = 0; i < _expensive_nodes->length(); i++) {
4545     Node* n = _expensive_nodes->at(i);
4546     if (!n->is_unreachable(igvn)) {
4547       assert(n->is_expensive(), "should be expensive");
4548       _expensive_nodes->at_put(j, n);
4549       j++;
4550     }
4551   }
4552   _expensive_nodes->trunc_to(j);
4553 
4554   // Then sort the list so that similar nodes are next to each other
4555   // and check for at least two nodes of identical kind with same data
4556   // inputs.
4557   sort_expensive_nodes();
4558 
4559   for (int i = 0; i < _expensive_nodes->length()-1; i++) {
4560     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
4561       return true;
4562     }
4563   }
4564 
4565   return false;
4566 }
4567 
4568 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
4569   if (_expensive_nodes->length() == 0) {
4570     return;
4571   }
4572 
4573   assert(OptimizeExpensiveOps, "optimization off?");
4574 
4575   // Sort to bring similar nodes next to each other and clear the
4576   // control input of nodes for which there's only a single copy.
4577   sort_expensive_nodes();
4578 
4579   int j = 0;
4580   int identical = 0;
4581   int i = 0;
4582   bool modified = false;
4583   for (; i < _expensive_nodes->length()-1; i++) {
4584     assert(j <= i, "can't write beyond current index");
4585     if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
4586       identical++;
4587       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4588       continue;
4589     }
4590     if (identical > 0) {
4591       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4592       identical = 0;
4593     } else {
4594       Node* n = _expensive_nodes->at(i);
4595       igvn.replace_input_of(n, 0, NULL);
4596       igvn.hash_insert(n);
4597       modified = true;
4598     }
4599   }
4600   if (identical > 0) {
4601     _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4602   } else if (_expensive_nodes->length() >= 1) {
4603     Node* n = _expensive_nodes->at(i);
4604     igvn.replace_input_of(n, 0, NULL);
4605     igvn.hash_insert(n);
4606     modified = true;
4607   }
4608   _expensive_nodes->trunc_to(j);
4609   if (modified) {
4610     igvn.optimize();
4611   }
4612 }
4613 
4614 void Compile::add_expensive_node(Node * n) {
4615   assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
4616   assert(n->is_expensive(), "expensive nodes with non-null control here only");
4617   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
4618   if (OptimizeExpensiveOps) {
4619     _expensive_nodes->append(n);
4620   } else {
4621     // Clear control input and let IGVN optimize expensive nodes if
4622     // OptimizeExpensiveOps is off.
4623     n->set_req(0, NULL);
4624   }
4625 }
4626 
4627 /**
4628  * Remove the speculative part of types and clean up the graph
4629  */
4630 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
4631   if (UseTypeSpeculation) {
4632     Unique_Node_List worklist;
4633     worklist.push(root());
4634     int modified = 0;
4635     // Go over all type nodes that carry a speculative type, drop the
4636     // speculative part of the type and enqueue the node for an igvn
4637     // which may optimize it out.
4638     for (uint next = 0; next < worklist.size(); ++next) {
4639       Node *n  = worklist.at(next);
4640       if (n->is_Type()) {
4641         TypeNode* tn = n->as_Type();
4642         const Type* t = tn->type();
4643         const Type* t_no_spec = t->remove_speculative();
4644         if (t_no_spec != t) {
4645           bool in_hash = igvn.hash_delete(n);
4646           assert(in_hash || (UseShenandoahGC && n->hash() == Node::NO_HASH), "node should be in igvn hash table");
4647           tn->set_type(t_no_spec);
4648           igvn.hash_insert(n);
4649           igvn._worklist.push(n); // give it a chance to go away
4650           modified++;
4651         }
4652       }
4653       uint max = n->len();
4654       for( uint i = 0; i < max; ++i ) {
4655         Node *m = n->in(i);
4656         if (not_a_node(m))  continue;
4657         worklist.push(m);
4658       }
4659     }
4660     // Drop the speculative part of all types in the igvn's type table
4661     igvn.remove_speculative_types();
4662     if (modified > 0) {
4663       igvn.optimize();
4664     }
4665 #ifdef ASSERT
4666     // Verify that after the IGVN is over no speculative type has resurfaced
4667     worklist.clear();
4668     worklist.push(root());
4669     for (uint next = 0; next < worklist.size(); ++next) {
4670       Node *n  = worklist.at(next);
4671       const Type* t = igvn.type_or_null(n);
4672       assert((t == NULL) || (t == t->remove_speculative()), "no more speculative types");
4673       if (n->is_Type()) {
4674         t = n->as_Type()->type();
4675         assert(t == t->remove_speculative(), "no more speculative types");
4676       }
4677       uint max = n->len();
4678       for( uint i = 0; i < max; ++i ) {
4679         Node *m = n->in(i);
4680         if (not_a_node(m))  continue;
4681         worklist.push(m);
4682       }
4683     }
4684     igvn.check_no_speculative_types();
4685 #endif
4686   }
4687 }
4688 
4689 // Auxiliary method to support randomized stressing/fuzzing.
4690 //
4691 // This method can be called the arbitrary number of times, with current count
4692 // as the argument. The logic allows selecting a single candidate from the
4693 // running list of candidates as follows:
4694 //    int count = 0;
4695 //    Cand* selected = null;
4696 //    while(cand = cand->next()) {
4697 //      if (randomized_select(++count)) {
4698 //        selected = cand;
4699 //      }
4700 //    }
4701 //
4702 // Including count equalizes the chances any candidate is "selected".
4703 // This is useful when we don't have the complete list of candidates to choose
4704 // from uniformly. In this case, we need to adjust the randomicity of the
4705 // selection, or else we will end up biasing the selection towards the latter
4706 // candidates.
4707 //
4708 // Quick back-envelope calculation shows that for the list of n candidates
4709 // the equal probability for the candidate to persist as "best" can be
4710 // achieved by replacing it with "next" k-th candidate with the probability
4711 // of 1/k. It can be easily shown that by the end of the run, the
4712 // probability for any candidate is converged to 1/n, thus giving the
4713 // uniform distribution among all the candidates.
4714 //
4715 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
4716 #define RANDOMIZED_DOMAIN_POW 29
4717 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
4718 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
4719 bool Compile::randomized_select(int count) {
4720   assert(count > 0, "only positive");
4721   return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);
4722 }
4723 
4724 CloneMap&     Compile::clone_map()                 { return _clone_map; }
4725 void          Compile::set_clone_map(Dict* d)      { _clone_map._dict = d; }
4726 
4727 void NodeCloneInfo::dump() const {
4728   tty->print(" {%d:%d} ", idx(), gen());
4729 }
4730 
4731 void CloneMap::clone(Node* old, Node* nnn, int gen) {
4732   uint64_t val = value(old->_idx);
4733   NodeCloneInfo cio(val);
4734   assert(val != 0, "old node should be in the map");
4735   NodeCloneInfo cin(cio.idx(), gen + cio.gen());
4736   insert(nnn->_idx, cin.get());
4737 #ifndef PRODUCT
4738   if (is_debug()) {
4739     tty->print_cr("CloneMap::clone inserted node %d info {%d:%d} into CloneMap", nnn->_idx, cin.idx(), cin.gen());
4740   }
4741 #endif
4742 }
4743 
4744 void CloneMap::verify_insert_and_clone(Node* old, Node* nnn, int gen) {
4745   NodeCloneInfo cio(value(old->_idx));
4746   if (cio.get() == 0) {
4747     cio.set(old->_idx, 0);
4748     insert(old->_idx, cio.get());
4749 #ifndef PRODUCT
4750     if (is_debug()) {
4751       tty->print_cr("CloneMap::verify_insert_and_clone inserted node %d info {%d:%d} into CloneMap", old->_idx, cio.idx(), cio.gen());
4752     }
4753 #endif
4754   }
4755   clone(old, nnn, gen);
4756 }
4757 
4758 int CloneMap::max_gen() const {
4759   int g = 0;
4760   DictI di(_dict);
4761   for(; di.test(); ++di) {
4762     int t = gen(di._key);
4763     if (g < t) {
4764       g = t;
4765 #ifndef PRODUCT
4766       if (is_debug()) {
4767         tty->print_cr("CloneMap::max_gen() update max=%d from %d", g, _2_node_idx_t(di._key));
4768       }
4769 #endif
4770     }
4771   }
4772   return g;
4773 }
4774 
4775 void CloneMap::dump(node_idx_t key) const {
4776   uint64_t val = value(key);
4777   if (val != 0) {
4778     NodeCloneInfo ni(val);
4779     ni.dump();
4780   }
4781 }