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/valuetypenode.hpp"
  71 #include "opto/vectornode.hpp"
  72 #include "runtime/arguments.hpp"
  73 #include "runtime/sharedRuntime.hpp"
  74 #include "runtime/signature.hpp"
  75 #include "runtime/stubRoutines.hpp"
  76 #include "runtime/timer.hpp"
  77 #include "utilities/align.hpp"
  78 #include "utilities/copy.hpp"
  79 #include "utilities/macros.hpp"
  80 #if INCLUDE_ZGC
  81 #include "gc/z/c2/zBarrierSetC2.hpp"
  82 #endif
  83 
  84 
  85 // -------------------- Compile::mach_constant_base_node -----------------------
  86 // Constant table base node singleton.
  87 MachConstantBaseNode* Compile::mach_constant_base_node() {
  88   if (_mach_constant_base_node == NULL) {
  89     _mach_constant_base_node = new MachConstantBaseNode();
  90     _mach_constant_base_node->add_req(C->root());
  91   }
  92   return _mach_constant_base_node;
  93 }
  94 
  95 
  96 /// Support for intrinsics.
  97 
  98 // Return the index at which m must be inserted (or already exists).
  99 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
 100 class IntrinsicDescPair {
 101  private:
 102   ciMethod* _m;
 103   bool _is_virtual;
 104  public:
 105   IntrinsicDescPair(ciMethod* m, bool is_virtual) : _m(m), _is_virtual(is_virtual) {}
 106   static int compare(IntrinsicDescPair* const& key, CallGenerator* const& elt) {
 107     ciMethod* m= elt->method();
 108     ciMethod* key_m = key->_m;
 109     if (key_m < m)      return -1;
 110     else if (key_m > m) return 1;
 111     else {
 112       bool is_virtual = elt->is_virtual();
 113       bool key_virtual = key->_is_virtual;
 114       if (key_virtual < is_virtual)      return -1;
 115       else if (key_virtual > is_virtual) return 1;
 116       else                               return 0;
 117     }
 118   }
 119 };
 120 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual, bool& found) {
 121 #ifdef ASSERT
 122   for (int i = 1; i < _intrinsics->length(); i++) {
 123     CallGenerator* cg1 = _intrinsics->at(i-1);
 124     CallGenerator* cg2 = _intrinsics->at(i);
 125     assert(cg1->method() != cg2->method()
 126            ? cg1->method()     < cg2->method()
 127            : cg1->is_virtual() < cg2->is_virtual(),
 128            "compiler intrinsics list must stay sorted");
 129   }
 130 #endif
 131   IntrinsicDescPair pair(m, is_virtual);
 132   return _intrinsics->find_sorted<IntrinsicDescPair*, IntrinsicDescPair::compare>(&pair, found);
 133 }
 134 
 135 void Compile::register_intrinsic(CallGenerator* cg) {
 136   if (_intrinsics == NULL) {
 137     _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
 138   }
 139   int len = _intrinsics->length();
 140   bool found = false;
 141   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual(), found);
 142   assert(!found, "registering twice");
 143   _intrinsics->insert_before(index, cg);
 144   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
 145 }
 146 
 147 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
 148   assert(m->is_loaded(), "don't try this on unloaded methods");
 149   if (_intrinsics != NULL) {
 150     bool found = false;
 151     int index = intrinsic_insertion_index(m, is_virtual, found);
 152      if (found) {
 153       return _intrinsics->at(index);
 154     }
 155   }
 156   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
 157   if (m->intrinsic_id() != vmIntrinsics::_none &&
 158       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
 159     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
 160     if (cg != NULL) {
 161       // Save it for next time:
 162       register_intrinsic(cg);
 163       return cg;
 164     } else {
 165       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
 166     }
 167   }
 168   return NULL;
 169 }
 170 
 171 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
 172 // in library_call.cpp.
 173 
 174 
 175 #ifndef PRODUCT
 176 // statistics gathering...
 177 
 178 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
 179 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
 180 
 181 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
 182   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
 183   int oflags = _intrinsic_hist_flags[id];
 184   assert(flags != 0, "what happened?");
 185   if (is_virtual) {
 186     flags |= _intrinsic_virtual;
 187   }
 188   bool changed = (flags != oflags);
 189   if ((flags & _intrinsic_worked) != 0) {
 190     juint count = (_intrinsic_hist_count[id] += 1);
 191     if (count == 1) {
 192       changed = true;           // first time
 193     }
 194     // increment the overall count also:
 195     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
 196   }
 197   if (changed) {
 198     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
 199       // Something changed about the intrinsic's virtuality.
 200       if ((flags & _intrinsic_virtual) != 0) {
 201         // This is the first use of this intrinsic as a virtual call.
 202         if (oflags != 0) {
 203           // We already saw it as a non-virtual, so note both cases.
 204           flags |= _intrinsic_both;
 205         }
 206       } else if ((oflags & _intrinsic_both) == 0) {
 207         // This is the first use of this intrinsic as a non-virtual
 208         flags |= _intrinsic_both;
 209       }
 210     }
 211     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
 212   }
 213   // update the overall flags also:
 214   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
 215   return changed;
 216 }
 217 
 218 static char* format_flags(int flags, char* buf) {
 219   buf[0] = 0;
 220   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
 221   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
 222   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
 223   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
 224   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
 225   if (buf[0] == 0)  strcat(buf, ",");
 226   assert(buf[0] == ',', "must be");
 227   return &buf[1];
 228 }
 229 
 230 void Compile::print_intrinsic_statistics() {
 231   char flagsbuf[100];
 232   ttyLocker ttyl;
 233   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
 234   tty->print_cr("Compiler intrinsic usage:");
 235   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
 236   if (total == 0)  total = 1;  // avoid div0 in case of no successes
 237   #define PRINT_STAT_LINE(name, c, f) \
 238     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
 239   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
 240     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
 241     int   flags = _intrinsic_hist_flags[id];
 242     juint count = _intrinsic_hist_count[id];
 243     if ((flags | count) != 0) {
 244       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
 245     }
 246   }
 247   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
 248   if (xtty != NULL)  xtty->tail("statistics");
 249 }
 250 
 251 void Compile::print_statistics() {
 252   { ttyLocker ttyl;
 253     if (xtty != NULL)  xtty->head("statistics type='opto'");
 254     Parse::print_statistics();
 255     PhaseCCP::print_statistics();
 256     PhaseRegAlloc::print_statistics();
 257     Scheduling::print_statistics();
 258     PhasePeephole::print_statistics();
 259     PhaseIdealLoop::print_statistics();
 260     if (xtty != NULL)  xtty->tail("statistics");
 261   }
 262   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
 263     // put this under its own <statistics> element.
 264     print_intrinsic_statistics();
 265   }
 266 }
 267 #endif //PRODUCT
 268 
 269 // Support for bundling info
 270 Bundle* Compile::node_bundling(const Node *n) {
 271   assert(valid_bundle_info(n), "oob");
 272   return &_node_bundling_base[n->_idx];
 273 }
 274 
 275 bool Compile::valid_bundle_info(const Node *n) {
 276   return (_node_bundling_limit > n->_idx);
 277 }
 278 
 279 
 280 void Compile::gvn_replace_by(Node* n, Node* nn) {
 281   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
 282     Node* use = n->last_out(i);
 283     bool is_in_table = initial_gvn()->hash_delete(use);
 284     uint uses_found = 0;
 285     for (uint j = 0; j < use->len(); j++) {
 286       if (use->in(j) == n) {
 287         if (j < use->req())
 288           use->set_req(j, nn);
 289         else
 290           use->set_prec(j, nn);
 291         uses_found++;
 292       }
 293     }
 294     if (is_in_table) {
 295       // reinsert into table
 296       initial_gvn()->hash_find_insert(use);
 297     }
 298     record_for_igvn(use);
 299     i -= uses_found;    // we deleted 1 or more copies of this edge
 300   }
 301 }
 302 
 303 
 304 static inline bool not_a_node(const Node* n) {
 305   if (n == NULL)                   return true;
 306   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
 307   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
 308   return false;
 309 }
 310 
 311 // Identify all nodes that are reachable from below, useful.
 312 // Use breadth-first pass that records state in a Unique_Node_List,
 313 // recursive traversal is slower.
 314 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
 315   int estimated_worklist_size = live_nodes();
 316   useful.map( estimated_worklist_size, NULL );  // preallocate space
 317 
 318   // Initialize worklist
 319   if (root() != NULL)     { useful.push(root()); }
 320   // If 'top' is cached, declare it useful to preserve cached node
 321   if( cached_top_node() ) { useful.push(cached_top_node()); }
 322 
 323   // Push all useful nodes onto the list, breadthfirst
 324   for( uint next = 0; next < useful.size(); ++next ) {
 325     assert( next < unique(), "Unique useful nodes < total nodes");
 326     Node *n  = useful.at(next);
 327     uint max = n->len();
 328     for( uint i = 0; i < max; ++i ) {
 329       Node *m = n->in(i);
 330       if (not_a_node(m))  continue;
 331       useful.push(m);
 332     }
 333   }
 334 }
 335 
 336 // Update dead_node_list with any missing dead nodes using useful
 337 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
 338 void Compile::update_dead_node_list(Unique_Node_List &useful) {
 339   uint max_idx = unique();
 340   VectorSet& useful_node_set = useful.member_set();
 341 
 342   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
 343     // If node with index node_idx is not in useful set,
 344     // mark it as dead in dead node list.
 345     if (! useful_node_set.test(node_idx) ) {
 346       record_dead_node(node_idx);
 347     }
 348   }
 349 }
 350 
 351 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
 352   int shift = 0;
 353   for (int i = 0; i < inlines->length(); i++) {
 354     CallGenerator* cg = inlines->at(i);
 355     CallNode* call = cg->call_node();
 356     if (shift > 0) {
 357       inlines->at_put(i-shift, cg);
 358     }
 359     if (!useful.member(call)) {
 360       shift++;
 361     }
 362   }
 363   inlines->trunc_to(inlines->length()-shift);
 364 }
 365 
 366 // Disconnect all useless nodes by disconnecting those at the boundary.
 367 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
 368   uint next = 0;
 369   while (next < useful.size()) {
 370     Node *n = useful.at(next++);
 371     if (n->is_SafePoint()) {
 372       // We're done with a parsing phase. Replaced nodes are not valid
 373       // beyond that point.
 374       n->as_SafePoint()->delete_replaced_nodes();
 375     }
 376     // Use raw traversal of out edges since this code removes out edges
 377     int max = n->outcnt();
 378     for (int j = 0; j < max; ++j) {
 379       Node* child = n->raw_out(j);
 380       if (! useful.member(child)) {
 381         assert(!child->is_top() || child != top(),
 382                "If top is cached in Compile object it is in useful list");
 383         // Only need to remove this out-edge to the useless node
 384         n->raw_del_out(j);
 385         --j;
 386         --max;
 387       }
 388     }
 389     if (n->outcnt() == 1 && n->has_special_unique_user()) {
 390       record_for_igvn(n->unique_out());
 391     }
 392   }
 393   // Remove useless macro and predicate opaq nodes
 394   for (int i = C->macro_count()-1; i >= 0; i--) {
 395     Node* n = C->macro_node(i);
 396     if (!useful.member(n)) {
 397       remove_macro_node(n);
 398     }
 399   }
 400   // Remove useless CastII nodes with range check dependency
 401   for (int i = range_check_cast_count() - 1; i >= 0; i--) {
 402     Node* cast = range_check_cast_node(i);
 403     if (!useful.member(cast)) {
 404       remove_range_check_cast(cast);
 405     }
 406   }
 407   // Remove useless expensive nodes
 408   for (int i = C->expensive_count()-1; i >= 0; i--) {
 409     Node* n = C->expensive_node(i);
 410     if (!useful.member(n)) {
 411       remove_expensive_node(n);
 412     }
 413   }
 414   // Remove useless Opaque4 nodes
 415   for (int i = opaque4_count() - 1; i >= 0; i--) {
 416     Node* opaq = opaque4_node(i);
 417     if (!useful.member(opaq)) {
 418       remove_opaque4_node(opaq);
 419     }
 420   }
 421   // Remove useless value type nodes
 422   if (_value_type_nodes != NULL) {
 423     _value_type_nodes->remove_useless_nodes(useful.member_set());
 424   }
 425   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 426   bs->eliminate_useless_gc_barriers(useful, this);
 427   // clean up the late inline lists
 428   remove_useless_late_inlines(&_string_late_inlines, useful);
 429   remove_useless_late_inlines(&_boxing_late_inlines, useful);
 430   remove_useless_late_inlines(&_late_inlines, useful);
 431   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
 432 }
 433 
 434 //------------------------------frame_size_in_words-----------------------------
 435 // frame_slots in units of words
 436 int Compile::frame_size_in_words() const {
 437   // shift is 0 in LP32 and 1 in LP64
 438   const int shift = (LogBytesPerWord - LogBytesPerInt);
 439   int words = _frame_slots >> shift;
 440   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
 441   return words;
 442 }
 443 
 444 // To bang the stack of this compiled method we use the stack size
 445 // that the interpreter would need in case of a deoptimization. This
 446 // removes the need to bang the stack in the deoptimization blob which
 447 // in turn simplifies stack overflow handling.
 448 int Compile::bang_size_in_bytes() const {
 449   return MAX2(frame_size_in_bytes() + os::extra_bang_size_in_bytes(), _interpreter_frame_size);
 450 }
 451 
 452 // ============================================================================
 453 //------------------------------CompileWrapper---------------------------------
 454 class CompileWrapper : public StackObj {
 455   Compile *const _compile;
 456  public:
 457   CompileWrapper(Compile* compile);
 458 
 459   ~CompileWrapper();
 460 };
 461 
 462 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
 463   // the Compile* pointer is stored in the current ciEnv:
 464   ciEnv* env = compile->env();
 465   assert(env == ciEnv::current(), "must already be a ciEnv active");
 466   assert(env->compiler_data() == NULL, "compile already active?");
 467   env->set_compiler_data(compile);
 468   assert(compile == Compile::current(), "sanity");
 469 
 470   compile->set_type_dict(NULL);
 471   compile->set_clone_map(new Dict(cmpkey, hashkey, _compile->comp_arena()));
 472   compile->clone_map().set_clone_idx(0);
 473   compile->set_type_hwm(NULL);
 474   compile->set_type_last_size(0);
 475   compile->set_last_tf(NULL, NULL);
 476   compile->set_indexSet_arena(NULL);
 477   compile->set_indexSet_free_block_list(NULL);
 478   compile->init_type_arena();
 479   Type::Initialize(compile);
 480   _compile->set_scratch_buffer_blob(NULL);
 481   _compile->begin_method();
 482   _compile->clone_map().set_debug(_compile->has_method() && _compile->directive()->CloneMapDebugOption);
 483 }
 484 CompileWrapper::~CompileWrapper() {
 485   _compile->end_method();
 486   if (_compile->scratch_buffer_blob() != NULL)
 487     BufferBlob::free(_compile->scratch_buffer_blob());
 488   _compile->env()->set_compiler_data(NULL);
 489 }
 490 
 491 
 492 //----------------------------print_compile_messages---------------------------
 493 void Compile::print_compile_messages() {
 494 #ifndef PRODUCT
 495   // Check if recompiling
 496   if (_subsume_loads == false && PrintOpto) {
 497     // Recompiling without allowing machine instructions to subsume loads
 498     tty->print_cr("*********************************************************");
 499     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
 500     tty->print_cr("*********************************************************");
 501   }
 502   if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
 503     // Recompiling without escape analysis
 504     tty->print_cr("*********************************************************");
 505     tty->print_cr("** Bailout: Recompile without escape analysis          **");
 506     tty->print_cr("*********************************************************");
 507   }
 508   if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
 509     // Recompiling without boxing elimination
 510     tty->print_cr("*********************************************************");
 511     tty->print_cr("** Bailout: Recompile without boxing elimination       **");
 512     tty->print_cr("*********************************************************");
 513   }
 514   if (C->directive()->BreakAtCompileOption) {
 515     // Open the debugger when compiling this method.
 516     tty->print("### Breaking when compiling: ");
 517     method()->print_short_name();
 518     tty->cr();
 519     BREAKPOINT;
 520   }
 521 
 522   if( PrintOpto ) {
 523     if (is_osr_compilation()) {
 524       tty->print("[OSR]%3d", _compile_id);
 525     } else {
 526       tty->print("%3d", _compile_id);
 527     }
 528   }
 529 #endif
 530 }
 531 
 532 
 533 //-----------------------init_scratch_buffer_blob------------------------------
 534 // Construct a temporary BufferBlob and cache it for this compile.
 535 void Compile::init_scratch_buffer_blob(int const_size) {
 536   // If there is already a scratch buffer blob allocated and the
 537   // constant section is big enough, use it.  Otherwise free the
 538   // current and allocate a new one.
 539   BufferBlob* blob = scratch_buffer_blob();
 540   if ((blob != NULL) && (const_size <= _scratch_const_size)) {
 541     // Use the current blob.
 542   } else {
 543     if (blob != NULL) {
 544       BufferBlob::free(blob);
 545     }
 546 
 547     ResourceMark rm;
 548     _scratch_const_size = const_size;
 549     int size = C2Compiler::initial_code_buffer_size(const_size);
 550     blob = BufferBlob::create("Compile::scratch_buffer", size);
 551     // Record the buffer blob for next time.
 552     set_scratch_buffer_blob(blob);
 553     // Have we run out of code space?
 554     if (scratch_buffer_blob() == NULL) {
 555       // Let CompilerBroker disable further compilations.
 556       record_failure("Not enough space for scratch buffer in CodeCache");
 557       return;
 558     }
 559   }
 560 
 561   // Initialize the relocation buffers
 562   relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
 563   set_scratch_locs_memory(locs_buf);
 564 }
 565 
 566 
 567 //-----------------------scratch_emit_size-------------------------------------
 568 // Helper function that computes size by emitting code
 569 uint Compile::scratch_emit_size(const Node* n) {
 570   // Start scratch_emit_size section.
 571   set_in_scratch_emit_size(true);
 572 
 573   // Emit into a trash buffer and count bytes emitted.
 574   // This is a pretty expensive way to compute a size,
 575   // but it works well enough if seldom used.
 576   // All common fixed-size instructions are given a size
 577   // method by the AD file.
 578   // Note that the scratch buffer blob and locs memory are
 579   // allocated at the beginning of the compile task, and
 580   // may be shared by several calls to scratch_emit_size.
 581   // The allocation of the scratch buffer blob is particularly
 582   // expensive, since it has to grab the code cache lock.
 583   BufferBlob* blob = this->scratch_buffer_blob();
 584   assert(blob != NULL, "Initialize BufferBlob at start");
 585   assert(blob->size() > MAX_inst_size, "sanity");
 586   relocInfo* locs_buf = scratch_locs_memory();
 587   address blob_begin = blob->content_begin();
 588   address blob_end   = (address)locs_buf;
 589   assert(blob->contains(blob_end), "sanity");
 590   CodeBuffer buf(blob_begin, blob_end - blob_begin);
 591   buf.initialize_consts_size(_scratch_const_size);
 592   buf.initialize_stubs_size(MAX_stubs_size);
 593   assert(locs_buf != NULL, "sanity");
 594   int lsize = MAX_locs_size / 3;
 595   buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
 596   buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
 597   buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
 598   // Mark as scratch buffer.
 599   buf.consts()->set_scratch_emit();
 600   buf.insts()->set_scratch_emit();
 601   buf.stubs()->set_scratch_emit();
 602 
 603   // Do the emission.
 604 
 605   Label fakeL; // Fake label for branch instructions.
 606   Label*   saveL = NULL;
 607   uint save_bnum = 0;
 608   bool is_branch = n->is_MachBranch();
 609   if (is_branch) {
 610     MacroAssembler masm(&buf);
 611     masm.bind(fakeL);
 612     n->as_MachBranch()->save_label(&saveL, &save_bnum);
 613     n->as_MachBranch()->label_set(&fakeL, 0);
 614   }
 615   n->emit(buf, this->regalloc());
 616 
 617   // Emitting into the scratch buffer should not fail
 618   assert (!failing(), "Must not have pending failure. Reason is: %s", failure_reason());
 619 
 620   // Restore label.
 621   if (is_branch) {
 622     n->as_MachBranch()->label_set(saveL, save_bnum);
 623   }
 624 
 625   // End scratch_emit_size section.
 626   set_in_scratch_emit_size(false);
 627 
 628   return buf.insts_size();
 629 }
 630 
 631 
 632 // ============================================================================
 633 //------------------------------Compile standard-------------------------------
 634 debug_only( int Compile::_debug_idx = 100000; )
 635 
 636 // Compile a method.  entry_bci is -1 for normal compilations and indicates
 637 // the continuation bci for on stack replacement.
 638 
 639 
 640 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
 641                   bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing, DirectiveSet* directive)
 642                 : Phase(Compiler),
 643                   _compile_id(ci_env->compile_id()),
 644                   _save_argument_registers(false),
 645                   _subsume_loads(subsume_loads),
 646                   _do_escape_analysis(do_escape_analysis),
 647                   _eliminate_boxing(eliminate_boxing),
 648                   _method(target),
 649                   _entry_bci(osr_bci),
 650                   _stub_function(NULL),
 651                   _stub_name(NULL),
 652                   _stub_entry_point(NULL),
 653                   _max_node_limit(MaxNodeLimit),
 654                   _orig_pc_slot(0),
 655                   _orig_pc_slot_offset_in_bytes(0),
 656                   _inlining_progress(false),
 657                   _inlining_incrementally(false),
 658                   _has_reserved_stack_access(target->has_reserved_stack_access()),
 659 #ifndef PRODUCT
 660                   _trace_opto_output(directive->TraceOptoOutputOption),
 661 #endif
 662                   _has_method_handle_invokes(false),
 663                   _comp_arena(mtCompiler),
 664                   _barrier_set_state(BarrierSet::barrier_set()->barrier_set_c2()->create_barrier_state(comp_arena())),
 665                   _env(ci_env),
 666                   _directive(directive),
 667                   _log(ci_env->log()),
 668                   _failure_reason(NULL),
 669                   _congraph(NULL),
 670 #ifndef PRODUCT
 671                   _printer(IdealGraphPrinter::printer()),
 672 #endif
 673                   _dead_node_list(comp_arena()),
 674                   _dead_node_count(0),
 675                   _node_arena(mtCompiler),
 676                   _old_arena(mtCompiler),
 677                   _mach_constant_base_node(NULL),
 678                   _Compile_types(mtCompiler),
 679                   _initial_gvn(NULL),
 680                   _for_igvn(NULL),
 681                   _warm_calls(NULL),
 682                   _late_inlines(comp_arena(), 2, 0, NULL),
 683                   _string_late_inlines(comp_arena(), 2, 0, NULL),
 684                   _boxing_late_inlines(comp_arena(), 2, 0, NULL),
 685                   _late_inlines_pos(0),
 686                   _number_of_mh_late_inlines(0),
 687                   _print_inlining_stream(NULL),
 688                   _print_inlining_list(NULL),
 689                   _print_inlining_idx(0),
 690                   _print_inlining_output(NULL),
 691                   _replay_inline_data(NULL),
 692                   _java_calls(0),
 693                   _inner_loops(0),
 694                   _interpreter_frame_size(0),
 695                   _node_bundling_limit(0),
 696                   _node_bundling_base(NULL),
 697                   _code_buffer("Compile::Fill_buffer"),
 698                   _scratch_const_size(-1),
 699                   _in_scratch_emit_size(false)
 700 #ifndef PRODUCT
 701                   , _in_dump_cnt(0)
 702 #endif
 703 {
 704   C = this;
 705 #ifndef PRODUCT
 706   if (_printer != NULL) {
 707     _printer->set_compile(this);
 708   }
 709 #endif
 710   CompileWrapper cw(this);
 711 
 712   if (CITimeVerbose) {
 713     tty->print(" ");
 714     target->holder()->name()->print();
 715     tty->print(".");
 716     target->print_short_name();
 717     tty->print("  ");
 718   }
 719   TraceTime t1("Total compilation time", &_t_totalCompilation, CITime, CITimeVerbose);
 720   TraceTime t2(NULL, &_t_methodCompilation, CITime, false);
 721 
 722 #ifndef PRODUCT
 723   bool print_opto_assembly = directive->PrintOptoAssemblyOption;
 724   if (!print_opto_assembly) {
 725     bool print_assembly = directive->PrintAssemblyOption;
 726     if (print_assembly && !Disassembler::can_decode()) {
 727       tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
 728       print_opto_assembly = true;
 729     }
 730   }
 731   set_print_assembly(print_opto_assembly);
 732   set_parsed_irreducible_loop(false);
 733 
 734   if (directive->ReplayInlineOption) {
 735     _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
 736   }
 737 #endif
 738   set_print_inlining(directive->PrintInliningOption || PrintOptoInlining);
 739   set_print_intrinsics(directive->PrintIntrinsicsOption);
 740   set_has_irreducible_loop(true); // conservative until build_loop_tree() reset it
 741 
 742   if (ProfileTraps RTM_OPT_ONLY( || UseRTMLocking )) {
 743     // Make sure the method being compiled gets its own MDO,
 744     // so we can at least track the decompile_count().
 745     // Need MDO to record RTM code generation state.
 746     method()->ensure_method_data();
 747   }
 748 
 749   Init(::AliasLevel);
 750 
 751 
 752   print_compile_messages();
 753 
 754   _ilt = InlineTree::build_inline_tree_root();
 755 
 756   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
 757   assert(num_alias_types() >= AliasIdxRaw, "");
 758 
 759 #define MINIMUM_NODE_HASH  1023
 760   // Node list that Iterative GVN will start with
 761   Unique_Node_List for_igvn(comp_arena());
 762   set_for_igvn(&for_igvn);
 763 
 764   // GVN that will be run immediately on new nodes
 765   uint estimated_size = method()->code_size()*4+64;
 766   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
 767   PhaseGVN gvn(node_arena(), estimated_size);
 768   set_initial_gvn(&gvn);
 769 
 770   print_inlining_init();
 771   { // Scope for timing the parser
 772     TracePhase tp("parse", &timers[_t_parser]);
 773 
 774     // Put top into the hash table ASAP.
 775     initial_gvn()->transform_no_reclaim(top());
 776 
 777     // Set up tf(), start(), and find a CallGenerator.
 778     CallGenerator* cg = NULL;
 779     if (is_osr_compilation()) {
 780       const TypeTuple *domain = StartOSRNode::osr_domain();
 781       const TypeTuple *range = TypeTuple::make_range(method()->signature());
 782       init_tf(TypeFunc::make(domain, range));
 783       StartNode* s = new StartOSRNode(root(), domain);
 784       initial_gvn()->set_type_bottom(s);
 785       init_start(s);
 786       cg = CallGenerator::for_osr(method(), entry_bci());
 787     } else {
 788       // Normal case.
 789       init_tf(TypeFunc::make(method()));
 790       StartNode* s = new StartNode(root(), tf()->domain_cc());
 791       initial_gvn()->set_type_bottom(s);
 792       init_start(s);
 793       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get) {
 794         // With java.lang.ref.reference.get() we must go through the
 795         // intrinsic - even when get() is the root
 796         // method of the compile - so that, if necessary, the value in
 797         // the referent field of the reference object gets recorded by
 798         // the pre-barrier code.
 799         cg = find_intrinsic(method(), false);
 800       }
 801       if (cg == NULL) {
 802         float past_uses = method()->interpreter_invocation_count();
 803         float expected_uses = past_uses;
 804         cg = CallGenerator::for_inline(method(), expected_uses);
 805       }
 806     }
 807     if (failing())  return;
 808     if (cg == NULL) {
 809       record_method_not_compilable("cannot parse method");
 810       return;
 811     }
 812     JVMState* jvms = build_start_state(start(), tf());
 813     if ((jvms = cg->generate(jvms)) == NULL) {
 814       if (!failure_reason_is(C2Compiler::retry_class_loading_during_parsing())) {
 815         record_method_not_compilable("method parse failed");
 816       }
 817       return;
 818     }
 819     GraphKit kit(jvms);
 820 
 821     if (!kit.stopped()) {
 822       // Accept return values, and transfer control we know not where.
 823       // This is done by a special, unique ReturnNode bound to root.
 824       return_values(kit.jvms());
 825     }
 826 
 827     if (kit.has_exceptions()) {
 828       // Any exceptions that escape from this call must be rethrown
 829       // to whatever caller is dynamically above us on the stack.
 830       // This is done by a special, unique RethrowNode bound to root.
 831       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
 832     }
 833 
 834     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
 835 
 836     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
 837       inline_string_calls(true);
 838     }
 839 
 840     if (failing())  return;
 841 
 842     print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
 843 
 844     // Remove clutter produced by parsing.
 845     if (!failing()) {
 846       ResourceMark rm;
 847       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
 848     }
 849   }
 850 
 851   // Note:  Large methods are capped off in do_one_bytecode().
 852   if (failing())  return;
 853 
 854   // After parsing, node notes are no longer automagic.
 855   // They must be propagated by register_new_node_with_optimizer(),
 856   // clone(), or the like.
 857   set_default_node_notes(NULL);
 858 
 859   for (;;) {
 860     int successes = Inline_Warm();
 861     if (failing())  return;
 862     if (successes == 0)  break;
 863   }
 864 
 865   // Drain the list.
 866   Finish_Warm();
 867 #ifndef PRODUCT
 868   if (_printer && _printer->should_print(1)) {
 869     _printer->print_inlining();
 870   }
 871 #endif
 872 
 873   if (failing())  return;
 874   NOT_PRODUCT( verify_graph_edges(); )
 875 
 876   // Now optimize
 877   Optimize();
 878   if (failing())  return;
 879   NOT_PRODUCT( verify_graph_edges(); )
 880 
 881 #ifndef PRODUCT
 882   if (PrintIdeal) {
 883     ttyLocker ttyl;  // keep the following output all in one block
 884     // This output goes directly to the tty, not the compiler log.
 885     // To enable tools to match it up with the compilation activity,
 886     // be sure to tag this tty output with the compile ID.
 887     if (xtty != NULL) {
 888       xtty->head("ideal compile_id='%d'%s", compile_id(),
 889                  is_osr_compilation()    ? " compile_kind='osr'" :
 890                  "");
 891     }
 892     root()->dump(9999);
 893     if (xtty != NULL) {
 894       xtty->tail("ideal");
 895     }
 896   }
 897 #endif
 898 
 899 #ifdef ASSERT
 900   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 901   bs->verify_gc_barriers(this, BarrierSetC2::BeforeCodeGen);
 902 #endif
 903 
 904   // Dump compilation data to replay it.
 905   if (directive->DumpReplayOption) {
 906     env()->dump_replay_data(_compile_id);
 907   }
 908   if (directive->DumpInlineOption && (ilt() != NULL)) {
 909     env()->dump_inline_data(_compile_id);
 910   }
 911 
 912   // Now that we know the size of all the monitors we can add a fixed slot
 913   // for the original deopt pc.
 914 
 915   _orig_pc_slot =  fixed_slots();
 916   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
 917   set_fixed_slots(next_slot);
 918 
 919   // Compute when to use implicit null checks. Used by matching trap based
 920   // nodes and NullCheck optimization.
 921   set_allowed_deopt_reasons();
 922 
 923   // Now generate code
 924   Code_Gen();
 925   if (failing())  return;
 926 
 927   // Check if we want to skip execution of all compiled code.
 928   {
 929 #ifndef PRODUCT
 930     if (OptoNoExecute) {
 931       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
 932       return;
 933     }
 934 #endif
 935     TracePhase tp("install_code", &timers[_t_registerMethod]);
 936 
 937     if (is_osr_compilation()) {
 938       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
 939       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
 940     } else {
 941       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
 942       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
 943     }
 944 
 945     env()->register_method(_method, _entry_bci,
 946                            &_code_offsets,
 947                            _orig_pc_slot_offset_in_bytes,
 948                            code_buffer(),
 949                            frame_size_in_words(), _oop_map_set,
 950                            &_handler_table, &_inc_table,
 951                            compiler,
 952                            has_unsafe_access(),
 953                            SharedRuntime::is_wide_vector(max_vector_size()),
 954                            rtm_state()
 955                            );
 956 
 957     if (log() != NULL) // Print code cache state into compiler log
 958       log()->code_cache_state();
 959   }
 960 }
 961 
 962 //------------------------------Compile----------------------------------------
 963 // Compile a runtime stub
 964 Compile::Compile( ciEnv* ci_env,
 965                   TypeFunc_generator generator,
 966                   address stub_function,
 967                   const char *stub_name,
 968                   int is_fancy_jump,
 969                   bool pass_tls,
 970                   bool save_arg_registers,
 971                   bool return_pc,
 972                   DirectiveSet* directive)
 973   : Phase(Compiler),
 974     _compile_id(0),
 975     _save_argument_registers(save_arg_registers),
 976     _subsume_loads(true),
 977     _do_escape_analysis(false),
 978     _eliminate_boxing(false),
 979     _method(NULL),
 980     _entry_bci(InvocationEntryBci),
 981     _stub_function(stub_function),
 982     _stub_name(stub_name),
 983     _stub_entry_point(NULL),
 984     _max_node_limit(MaxNodeLimit),
 985     _orig_pc_slot(0),
 986     _orig_pc_slot_offset_in_bytes(0),
 987     _inlining_progress(false),
 988     _inlining_incrementally(false),
 989     _has_reserved_stack_access(false),
 990 #ifndef PRODUCT
 991     _trace_opto_output(directive->TraceOptoOutputOption),
 992 #endif
 993     _has_method_handle_invokes(false),
 994     _comp_arena(mtCompiler),
 995     _env(ci_env),
 996     _directive(directive),
 997     _log(ci_env->log()),
 998     _failure_reason(NULL),
 999     _congraph(NULL),
1000 #ifndef PRODUCT
1001     _printer(NULL),
1002 #endif
1003     _dead_node_list(comp_arena()),
1004     _dead_node_count(0),
1005     _node_arena(mtCompiler),
1006     _old_arena(mtCompiler),
1007     _mach_constant_base_node(NULL),
1008     _Compile_types(mtCompiler),
1009     _initial_gvn(NULL),
1010     _for_igvn(NULL),
1011     _warm_calls(NULL),
1012     _number_of_mh_late_inlines(0),
1013     _print_inlining_stream(NULL),
1014     _print_inlining_list(NULL),
1015     _print_inlining_idx(0),
1016     _print_inlining_output(NULL),
1017     _replay_inline_data(NULL),
1018     _java_calls(0),
1019     _inner_loops(0),
1020     _interpreter_frame_size(0),
1021     _node_bundling_limit(0),
1022     _node_bundling_base(NULL),
1023     _code_buffer("Compile::Fill_buffer"),
1024 #ifndef PRODUCT
1025     _in_dump_cnt(0),
1026 #endif
1027     _allowed_reasons(0) {
1028   C = this;
1029 
1030   TraceTime t1(NULL, &_t_totalCompilation, CITime, false);
1031   TraceTime t2(NULL, &_t_stubCompilation, CITime, false);
1032 
1033 #ifndef PRODUCT
1034   set_print_assembly(PrintFrameConverterAssembly);
1035   set_parsed_irreducible_loop(false);
1036 #endif
1037   set_has_irreducible_loop(false); // no loops
1038 
1039   CompileWrapper cw(this);
1040   Init(/*AliasLevel=*/ 0);
1041   init_tf((*generator)());
1042 
1043   {
1044     // The following is a dummy for the sake of GraphKit::gen_stub
1045     Unique_Node_List for_igvn(comp_arena());
1046     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
1047     PhaseGVN gvn(Thread::current()->resource_area(),255);
1048     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
1049     gvn.transform_no_reclaim(top());
1050 
1051     GraphKit kit;
1052     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
1053   }
1054 
1055   NOT_PRODUCT( verify_graph_edges(); )
1056   Code_Gen();
1057   if (failing())  return;
1058 
1059 
1060   // Entry point will be accessed using compile->stub_entry_point();
1061   if (code_buffer() == NULL) {
1062     Matcher::soft_match_failure();
1063   } else {
1064     if (PrintAssembly && (WizardMode || Verbose))
1065       tty->print_cr("### Stub::%s", stub_name);
1066 
1067     if (!failing()) {
1068       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
1069 
1070       // Make the NMethod
1071       // For now we mark the frame as never safe for profile stackwalking
1072       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
1073                                                       code_buffer(),
1074                                                       CodeOffsets::frame_never_safe,
1075                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
1076                                                       frame_size_in_words(),
1077                                                       _oop_map_set,
1078                                                       save_arg_registers);
1079       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
1080 
1081       _stub_entry_point = rs->entry_point();
1082     }
1083   }
1084 }
1085 
1086 //------------------------------Init-------------------------------------------
1087 // Prepare for a single compilation
1088 void Compile::Init(int aliaslevel) {
1089   _unique  = 0;
1090   _regalloc = NULL;
1091 
1092   _tf      = NULL;  // filled in later
1093   _top     = NULL;  // cached later
1094   _matcher = NULL;  // filled in later
1095   _cfg     = NULL;  // filled in later
1096 
1097   set_24_bit_selection_and_mode(Use24BitFP, false);
1098 
1099   _node_note_array = NULL;
1100   _default_node_notes = NULL;
1101   DEBUG_ONLY( _modified_nodes = NULL; ) // Used in Optimize()
1102 
1103   _immutable_memory = NULL; // filled in at first inquiry
1104 
1105   // Globally visible Nodes
1106   // First set TOP to NULL to give safe behavior during creation of RootNode
1107   set_cached_top_node(NULL);
1108   set_root(new RootNode());
1109   // Now that you have a Root to point to, create the real TOP
1110   set_cached_top_node( new ConNode(Type::TOP) );
1111   set_recent_alloc(NULL, NULL);
1112 
1113   // Create Debug Information Recorder to record scopes, oopmaps, etc.
1114   env()->set_oop_recorder(new OopRecorder(env()->arena()));
1115   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
1116   env()->set_dependencies(new Dependencies(env()));
1117 
1118   _fixed_slots = 0;
1119   set_has_split_ifs(false);
1120   set_has_loops(has_method() && method()->has_loops()); // first approximation
1121   set_has_stringbuilder(false);
1122   set_has_boxed_value(false);
1123   _trap_can_recompile = false;  // no traps emitted yet
1124   _major_progress = true; // start out assuming good things will happen
1125   set_has_unsafe_access(false);
1126   set_max_vector_size(0);
1127   set_clear_upper_avx(false);  //false as default for clear upper bits of ymm registers
1128   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
1129   set_decompile_count(0);
1130 
1131   set_do_freq_based_layout(_directive->BlockLayoutByFrequencyOption);
1132   set_num_loop_opts(LoopOptsCount);
1133   set_do_inlining(Inline);
1134   set_max_inline_size(MaxInlineSize);
1135   set_freq_inline_size(FreqInlineSize);
1136   set_do_scheduling(OptoScheduling);
1137   set_do_count_invocations(false);
1138   set_do_method_data_update(false);
1139 
1140   set_do_vector_loop(false);
1141 
1142   if (AllowVectorizeOnDemand) {
1143     if (has_method() && (_directive->VectorizeOption || _directive->VectorizeDebugOption)) {
1144       set_do_vector_loop(true);
1145       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());})
1146     } else if (has_method() && method()->name() != 0 &&
1147                method()->intrinsic_id() == vmIntrinsics::_forEachRemaining) {
1148       set_do_vector_loop(true);
1149     }
1150   }
1151   set_use_cmove(UseCMoveUnconditionally /* || do_vector_loop()*/); //TODO: consider do_vector_loop() mandate use_cmove unconditionally
1152   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());})
1153 
1154   set_age_code(has_method() && method()->profile_aging());
1155   set_rtm_state(NoRTM); // No RTM lock eliding by default
1156   _max_node_limit = _directive->MaxNodeLimitOption;
1157 
1158 #if INCLUDE_RTM_OPT
1159   if (UseRTMLocking && has_method() && (method()->method_data_or_null() != NULL)) {
1160     int rtm_state = method()->method_data()->rtm_state();
1161     if (method_has_option("NoRTMLockEliding") || ((rtm_state & NoRTM) != 0)) {
1162       // Don't generate RTM lock eliding code.
1163       set_rtm_state(NoRTM);
1164     } else if (method_has_option("UseRTMLockEliding") || ((rtm_state & UseRTM) != 0) || !UseRTMDeopt) {
1165       // Generate RTM lock eliding code without abort ratio calculation code.
1166       set_rtm_state(UseRTM);
1167     } else if (UseRTMDeopt) {
1168       // Generate RTM lock eliding code and include abort ratio calculation
1169       // code if UseRTMDeopt is on.
1170       set_rtm_state(ProfileRTM);
1171     }
1172   }
1173 #endif
1174   if (debug_info()->recording_non_safepoints()) {
1175     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
1176                         (comp_arena(), 8, 0, NULL));
1177     set_default_node_notes(Node_Notes::make(this));
1178   }
1179 
1180   // // -- Initialize types before each compile --
1181   // // Update cached type information
1182   // if( _method && _method->constants() )
1183   //   Type::update_loaded_types(_method, _method->constants());
1184 
1185   // Init alias_type map.
1186   if (!_do_escape_analysis && aliaslevel == 3)
1187     aliaslevel = 2;  // No unique types without escape analysis
1188   _AliasLevel = aliaslevel;
1189   const int grow_ats = 16;
1190   _max_alias_types = grow_ats;
1191   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1192   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
1193   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1194   {
1195     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
1196   }
1197   // Initialize the first few types.
1198   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
1199   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1200   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1201   _num_alias_types = AliasIdxRaw+1;
1202   // Zero out the alias type cache.
1203   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1204   // A NULL adr_type hits in the cache right away.  Preload the right answer.
1205   probe_alias_cache(NULL)->_index = AliasIdxTop;
1206 
1207   _intrinsics = NULL;
1208   _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1209   _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1210   _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1211   _range_check_casts = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1212   _opaque4_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1213   _value_type_nodes = new (comp_arena()) Unique_Node_List(comp_arena());
1214   register_library_intrinsics();
1215 }
1216 
1217 //---------------------------init_start----------------------------------------
1218 // Install the StartNode on this compile object.
1219 void Compile::init_start(StartNode* s) {
1220   if (failing())
1221     return; // already failing
1222   assert(s == start(), "");
1223 }
1224 
1225 /**
1226  * Return the 'StartNode'. We must not have a pending failure, since the ideal graph
1227  * can be in an inconsistent state, i.e., we can get segmentation faults when traversing
1228  * the ideal graph.
1229  */
1230 StartNode* Compile::start() const {
1231   assert (!failing(), "Must not have pending failure. Reason is: %s", failure_reason());
1232   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1233     Node* start = root()->fast_out(i);
1234     if (start->is_Start()) {
1235       return start->as_Start();
1236     }
1237   }
1238   fatal("Did not find Start node!");
1239   return NULL;
1240 }
1241 
1242 //-------------------------------immutable_memory-------------------------------------
1243 // Access immutable memory
1244 Node* Compile::immutable_memory() {
1245   if (_immutable_memory != NULL) {
1246     return _immutable_memory;
1247   }
1248   StartNode* s = start();
1249   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1250     Node *p = s->fast_out(i);
1251     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1252       _immutable_memory = p;
1253       return _immutable_memory;
1254     }
1255   }
1256   ShouldNotReachHere();
1257   return NULL;
1258 }
1259 
1260 //----------------------set_cached_top_node------------------------------------
1261 // Install the cached top node, and make sure Node::is_top works correctly.
1262 void Compile::set_cached_top_node(Node* tn) {
1263   if (tn != NULL)  verify_top(tn);
1264   Node* old_top = _top;
1265   _top = tn;
1266   // Calling Node::setup_is_top allows the nodes the chance to adjust
1267   // their _out arrays.
1268   if (_top != NULL)     _top->setup_is_top();
1269   if (old_top != NULL)  old_top->setup_is_top();
1270   assert(_top == NULL || top()->is_top(), "");
1271 }
1272 
1273 #ifdef ASSERT
1274 uint Compile::count_live_nodes_by_graph_walk() {
1275   Unique_Node_List useful(comp_arena());
1276   // Get useful node list by walking the graph.
1277   identify_useful_nodes(useful);
1278   return useful.size();
1279 }
1280 
1281 void Compile::print_missing_nodes() {
1282 
1283   // Return if CompileLog is NULL and PrintIdealNodeCount is false.
1284   if ((_log == NULL) && (! PrintIdealNodeCount)) {
1285     return;
1286   }
1287 
1288   // This is an expensive function. It is executed only when the user
1289   // specifies VerifyIdealNodeCount option or otherwise knows the
1290   // additional work that needs to be done to identify reachable nodes
1291   // by walking the flow graph and find the missing ones using
1292   // _dead_node_list.
1293 
1294   Unique_Node_List useful(comp_arena());
1295   // Get useful node list by walking the graph.
1296   identify_useful_nodes(useful);
1297 
1298   uint l_nodes = C->live_nodes();
1299   uint l_nodes_by_walk = useful.size();
1300 
1301   if (l_nodes != l_nodes_by_walk) {
1302     if (_log != NULL) {
1303       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
1304       _log->stamp();
1305       _log->end_head();
1306     }
1307     VectorSet& useful_member_set = useful.member_set();
1308     int last_idx = l_nodes_by_walk;
1309     for (int i = 0; i < last_idx; i++) {
1310       if (useful_member_set.test(i)) {
1311         if (_dead_node_list.test(i)) {
1312           if (_log != NULL) {
1313             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
1314           }
1315           if (PrintIdealNodeCount) {
1316             // Print the log message to tty
1317               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
1318               useful.at(i)->dump();
1319           }
1320         }
1321       }
1322       else if (! _dead_node_list.test(i)) {
1323         if (_log != NULL) {
1324           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
1325         }
1326         if (PrintIdealNodeCount) {
1327           // Print the log message to tty
1328           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
1329         }
1330       }
1331     }
1332     if (_log != NULL) {
1333       _log->tail("mismatched_nodes");
1334     }
1335   }
1336 }
1337 void Compile::record_modified_node(Node* n) {
1338   if (_modified_nodes != NULL && !_inlining_incrementally &&
1339       n->outcnt() != 0 && !n->is_Con()) {
1340     _modified_nodes->push(n);
1341   }
1342 }
1343 
1344 void Compile::remove_modified_node(Node* n) {
1345   if (_modified_nodes != NULL) {
1346     _modified_nodes->remove(n);
1347   }
1348 }
1349 #endif
1350 
1351 #ifndef PRODUCT
1352 void Compile::verify_top(Node* tn) const {
1353   if (tn != NULL) {
1354     assert(tn->is_Con(), "top node must be a constant");
1355     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1356     assert(tn->in(0) != NULL, "must have live top node");
1357   }
1358 }
1359 #endif
1360 
1361 
1362 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1363 
1364 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1365   guarantee(arr != NULL, "");
1366   int num_blocks = arr->length();
1367   if (grow_by < num_blocks)  grow_by = num_blocks;
1368   int num_notes = grow_by * _node_notes_block_size;
1369   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1370   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1371   while (num_notes > 0) {
1372     arr->append(notes);
1373     notes     += _node_notes_block_size;
1374     num_notes -= _node_notes_block_size;
1375   }
1376   assert(num_notes == 0, "exact multiple, please");
1377 }
1378 
1379 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1380   if (source == NULL || dest == NULL)  return false;
1381 
1382   if (dest->is_Con())
1383     return false;               // Do not push debug info onto constants.
1384 
1385 #ifdef ASSERT
1386   // Leave a bread crumb trail pointing to the original node:
1387   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1388     dest->set_debug_orig(source);
1389   }
1390 #endif
1391 
1392   if (node_note_array() == NULL)
1393     return false;               // Not collecting any notes now.
1394 
1395   // This is a copy onto a pre-existing node, which may already have notes.
1396   // If both nodes have notes, do not overwrite any pre-existing notes.
1397   Node_Notes* source_notes = node_notes_at(source->_idx);
1398   if (source_notes == NULL || source_notes->is_clear())  return false;
1399   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
1400   if (dest_notes == NULL || dest_notes->is_clear()) {
1401     return set_node_notes_at(dest->_idx, source_notes);
1402   }
1403 
1404   Node_Notes merged_notes = (*source_notes);
1405   // The order of operations here ensures that dest notes will win...
1406   merged_notes.update_from(dest_notes);
1407   return set_node_notes_at(dest->_idx, &merged_notes);
1408 }
1409 
1410 
1411 //--------------------------allow_range_check_smearing-------------------------
1412 // Gating condition for coalescing similar range checks.
1413 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1414 // single covering check that is at least as strong as any of them.
1415 // If the optimization succeeds, the simplified (strengthened) range check
1416 // will always succeed.  If it fails, we will deopt, and then give up
1417 // on the optimization.
1418 bool Compile::allow_range_check_smearing() const {
1419   // If this method has already thrown a range-check,
1420   // assume it was because we already tried range smearing
1421   // and it failed.
1422   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1423   return !already_trapped;
1424 }
1425 
1426 
1427 //------------------------------flatten_alias_type-----------------------------
1428 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1429   int offset = tj->offset();
1430   TypePtr::PTR ptr = tj->ptr();
1431 
1432   // Known instance (scalarizable allocation) alias only with itself.
1433   bool is_known_inst = tj->isa_oopptr() != NULL &&
1434                        tj->is_oopptr()->is_known_instance();
1435 
1436   // Process weird unsafe references.
1437   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1438     bool default_value_load = EnableValhalla && tj->is_instptr()->klass() == ciEnv::current()->Class_klass();
1439     assert(InlineUnsafeOps || default_value_load, "indeterminate pointers come only from unsafe ops");
1440     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1441     tj = TypeOopPtr::BOTTOM;
1442     ptr = tj->ptr();
1443     offset = tj->offset();
1444   }
1445 
1446   // Array pointers need some flattening
1447   const TypeAryPtr *ta = tj->isa_aryptr();
1448   if (ta && ta->is_stable()) {
1449     // Erase stability property for alias analysis.
1450     tj = ta = ta->cast_to_stable(false);
1451   }
1452   if( ta && is_known_inst ) {
1453     if ( offset != Type::OffsetBot &&
1454          offset > arrayOopDesc::length_offset_in_bytes() ) {
1455       offset = Type::OffsetBot; // Flatten constant access into array body only
1456       tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, Type::Offset(offset), ta->field_offset(), ta->instance_id());
1457     }
1458   } else if( ta && _AliasLevel >= 2 ) {
1459     // For arrays indexed by constant indices, we flatten the alias
1460     // space to include all of the array body.  Only the header, klass
1461     // and array length can be accessed un-aliased.
1462     // For flattened value type array, each field has its own slice so
1463     // we must include the field offset.
1464     if( offset != Type::OffsetBot ) {
1465       if( ta->const_oop() ) { // MethodData* or Method*
1466         offset = Type::OffsetBot;   // Flatten constant access into array body
1467         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,Type::Offset(offset), ta->field_offset());
1468       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1469         // range is OK as-is.
1470         tj = ta = TypeAryPtr::RANGE;
1471       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1472         tj = TypeInstPtr::KLASS; // all klass loads look alike
1473         ta = TypeAryPtr::RANGE; // generic ignored junk
1474         ptr = TypePtr::BotPTR;
1475       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1476         tj = TypeInstPtr::MARK;
1477         ta = TypeAryPtr::RANGE; // generic ignored junk
1478         ptr = TypePtr::BotPTR;
1479       } else if (BarrierSet::barrier_set()->barrier_set_c2()->flatten_gc_alias_type(tj)) {
1480         ta = tj->isa_aryptr();
1481       } else {                  // Random constant offset into array body
1482         offset = Type::OffsetBot;   // Flatten constant access into array body
1483         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,Type::Offset(offset), ta->field_offset());
1484       }
1485     }
1486     // Arrays of fixed size alias with arrays of unknown size.
1487     if (ta->size() != TypeInt::POS) {
1488       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1489       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,Type::Offset(offset), ta->field_offset());
1490     }
1491     // Arrays of known objects become arrays of unknown objects.
1492     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1493       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1494       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,Type::Offset(offset), ta->field_offset());
1495     }
1496     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1497       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1498       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,Type::Offset(offset), ta->field_offset());
1499     }
1500     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1501     // cannot be distinguished by bytecode alone.
1502     if (ta->elem() == TypeInt::BOOL) {
1503       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1504       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1505       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,Type::Offset(offset), ta->field_offset());
1506     }
1507     // During the 2nd round of IterGVN, NotNull castings are removed.
1508     // Make sure the Bottom and NotNull variants alias the same.
1509     // Also, make sure exact and non-exact variants alias the same.
1510     if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != NULL) {
1511       tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,Type::Offset(offset), ta->field_offset());
1512     }
1513   }
1514 
1515   // Oop pointers need some flattening
1516   const TypeInstPtr *to = tj->isa_instptr();
1517   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1518     ciInstanceKlass *k = to->klass()->as_instance_klass();
1519     if( ptr == TypePtr::Constant ) {
1520       if (to->klass() != ciEnv::current()->Class_klass() ||
1521           offset < k->size_helper() * wordSize) {
1522         // No constant oop pointers (such as Strings); they alias with
1523         // unknown strings.
1524         assert(!is_known_inst, "not scalarizable allocation");
1525         tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,Type::Offset(offset));
1526       }
1527     } else if( is_known_inst ) {
1528       tj = to; // Keep NotNull and klass_is_exact for instance type
1529     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1530       // During the 2nd round of IterGVN, NotNull castings are removed.
1531       // Make sure the Bottom and NotNull variants alias the same.
1532       // Also, make sure exact and non-exact variants alias the same.
1533       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,Type::Offset(offset));
1534     }
1535     if (to->speculative() != NULL) {
1536       tj = to = TypeInstPtr::make(to->ptr(),to->klass(),to->klass_is_exact(),to->const_oop(),Type::Offset(to->offset()), to->instance_id());
1537     }
1538     // Canonicalize the holder of this field
1539     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1540       // First handle header references such as a LoadKlassNode, even if the
1541       // object's klass is unloaded at compile time (4965979).
1542       if (!is_known_inst) { // Do it only for non-instance types
1543         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, Type::Offset(offset));
1544       }
1545     } else if (BarrierSet::barrier_set()->barrier_set_c2()->flatten_gc_alias_type(tj)) {
1546       to = tj->is_instptr();
1547     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1548       // Static fields are in the space above the normal instance
1549       // fields in the java.lang.Class instance.
1550       if (to->klass() != ciEnv::current()->Class_klass()) {
1551         to = NULL;
1552         tj = TypeOopPtr::BOTTOM;
1553         offset = tj->offset();
1554       }
1555     } else {
1556       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1557       if (!k->equals(canonical_holder) || tj->offset() != offset) {
1558         if( is_known_inst ) {
1559           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, Type::Offset(offset), to->instance_id());
1560         } else {
1561           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, Type::Offset(offset));
1562         }
1563       }
1564     }
1565   }
1566 
1567   // Klass pointers to object array klasses need some flattening
1568   const TypeKlassPtr *tk = tj->isa_klassptr();
1569   if( tk ) {
1570     // If we are referencing a field within a Klass, we need
1571     // to assume the worst case of an Object.  Both exact and
1572     // inexact types must flatten to the same alias class so
1573     // use NotNull as the PTR.
1574     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1575 
1576       tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
1577                                    TypeKlassPtr::OBJECT->klass(),
1578                                    Type::Offset(offset));
1579     }
1580 
1581     ciKlass* klass = tk->klass();
1582     if (klass != NULL && klass->is_obj_array_klass()) {
1583       ciKlass* k = TypeAryPtr::OOPS->klass();
1584       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
1585         k = TypeInstPtr::BOTTOM->klass();
1586       tj = tk = TypeKlassPtr::make(TypePtr::NotNull, k, Type::Offset(offset));
1587     }
1588 
1589     // Check for precise loads from the primary supertype array and force them
1590     // to the supertype cache alias index.  Check for generic array loads from
1591     // the primary supertype array and also force them to the supertype cache
1592     // alias index.  Since the same load can reach both, we need to merge
1593     // these 2 disparate memories into the same alias class.  Since the
1594     // primary supertype array is read-only, there's no chance of confusion
1595     // where we bypass an array load and an array store.
1596     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1597     if (offset == Type::OffsetBot ||
1598         (offset >= primary_supers_offset &&
1599          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1600         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1601       offset = in_bytes(Klass::secondary_super_cache_offset());
1602       tj = tk = TypeKlassPtr::make(TypePtr::NotNull, tk->klass(), Type::Offset(offset));
1603     }
1604   }
1605 
1606   // Flatten all Raw pointers together.
1607   if (tj->base() == Type::RawPtr)
1608     tj = TypeRawPtr::BOTTOM;
1609 
1610   if (tj->base() == Type::AnyPtr)
1611     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
1612 
1613   // Flatten all to bottom for now
1614   switch( _AliasLevel ) {
1615   case 0:
1616     tj = TypePtr::BOTTOM;
1617     break;
1618   case 1:                       // Flatten to: oop, static, field or array
1619     switch (tj->base()) {
1620     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
1621     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
1622     case Type::AryPtr:   // do not distinguish arrays at all
1623     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
1624     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1625     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
1626     default: ShouldNotReachHere();
1627     }
1628     break;
1629   case 2:                       // No collapsing at level 2; keep all splits
1630   case 3:                       // No collapsing at level 3; keep all splits
1631     break;
1632   default:
1633     Unimplemented();
1634   }
1635 
1636   offset = tj->offset();
1637   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1638 
1639   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1640           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1641           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1642           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1643           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1644           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1645           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1646           (BarrierSet::barrier_set()->barrier_set_c2()->verify_gc_alias_type(tj, offset)),
1647           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1648   assert( tj->ptr() != TypePtr::TopPTR &&
1649           tj->ptr() != TypePtr::AnyNull &&
1650           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1651 //    assert( tj->ptr() != TypePtr::Constant ||
1652 //            tj->base() == Type::RawPtr ||
1653 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
1654 
1655   return tj;
1656 }
1657 
1658 void Compile::AliasType::Init(int i, const TypePtr* at) {
1659   _index = i;
1660   _adr_type = at;
1661   _field = NULL;
1662   _element = NULL;
1663   _is_rewritable = true; // default
1664   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1665   if (atoop != NULL && atoop->is_known_instance()) {
1666     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1667     _general_index = Compile::current()->get_alias_index(gt);
1668   } else {
1669     _general_index = 0;
1670   }
1671 }
1672 
1673 BasicType Compile::AliasType::basic_type() const {
1674   if (element() != NULL) {
1675     const Type* element = adr_type()->is_aryptr()->elem();
1676     return element->isa_narrowoop() ? T_OBJECT : element->array_element_basic_type();
1677   } if (field() != NULL) {
1678     return field()->layout_type();
1679   } else {
1680     return T_ILLEGAL; // unknown
1681   }
1682 }
1683 
1684 //---------------------------------print_on------------------------------------
1685 #ifndef PRODUCT
1686 void Compile::AliasType::print_on(outputStream* st) {
1687   if (index() < 10)
1688         st->print("@ <%d> ", index());
1689   else  st->print("@ <%d>",  index());
1690   st->print(is_rewritable() ? "   " : " RO");
1691   int offset = adr_type()->offset();
1692   if (offset == Type::OffsetBot)
1693         st->print(" +any");
1694   else  st->print(" +%-3d", offset);
1695   st->print(" in ");
1696   adr_type()->dump_on(st);
1697   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1698   if (field() != NULL && tjp) {
1699     if (tjp->klass()  != field()->holder() ||
1700         tjp->offset() != field()->offset_in_bytes()) {
1701       st->print(" != ");
1702       field()->print();
1703       st->print(" ***");
1704     }
1705   }
1706 }
1707 
1708 void print_alias_types() {
1709   Compile* C = Compile::current();
1710   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1711   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1712     C->alias_type(idx)->print_on(tty);
1713     tty->cr();
1714   }
1715 }
1716 #endif
1717 
1718 
1719 //----------------------------probe_alias_cache--------------------------------
1720 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1721   intptr_t key = (intptr_t) adr_type;
1722   key ^= key >> logAliasCacheSize;
1723   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1724 }
1725 
1726 
1727 //-----------------------------grow_alias_types--------------------------------
1728 void Compile::grow_alias_types() {
1729   const int old_ats  = _max_alias_types; // how many before?
1730   const int new_ats  = old_ats;          // how many more?
1731   const int grow_ats = old_ats+new_ats;  // how many now?
1732   _max_alias_types = grow_ats;
1733   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1734   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1735   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1736   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
1737 }
1738 
1739 
1740 //--------------------------------find_alias_type------------------------------
1741 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1742   if (_AliasLevel == 0)
1743     return alias_type(AliasIdxBot);
1744 
1745   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1746   if (ace->_adr_type == adr_type) {
1747     return alias_type(ace->_index);
1748   }
1749 
1750   // Handle special cases.
1751   if (adr_type == NULL)             return alias_type(AliasIdxTop);
1752   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
1753 
1754   // Do it the slow way.
1755   const TypePtr* flat = flatten_alias_type(adr_type);
1756 
1757 #ifdef ASSERT
1758   {
1759     ResourceMark rm;
1760     assert(flat == flatten_alias_type(flat), "not idempotent: adr_type = %s; flat = %s => %s",
1761            Type::str(adr_type), Type::str(flat), Type::str(flatten_alias_type(flat)));
1762     assert(flat != TypePtr::BOTTOM, "cannot alias-analyze an untyped ptr: adr_type = %s",
1763            Type::str(adr_type));
1764     if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1765       const TypeOopPtr* foop = flat->is_oopptr();
1766       // Scalarizable allocations have exact klass always.
1767       bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1768       const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1769       assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type: foop = %s; xoop = %s",
1770              Type::str(foop), Type::str(xoop));
1771     }
1772   }
1773 #endif
1774 
1775   int idx = AliasIdxTop;
1776   for (int i = 0; i < num_alias_types(); i++) {
1777     if (alias_type(i)->adr_type() == flat) {
1778       idx = i;
1779       break;
1780     }
1781   }
1782 
1783   if (idx == AliasIdxTop) {
1784     if (no_create)  return NULL;
1785     // Grow the array if necessary.
1786     if (_num_alias_types == _max_alias_types)  grow_alias_types();
1787     // Add a new alias type.
1788     idx = _num_alias_types++;
1789     _alias_types[idx]->Init(idx, flat);
1790     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
1791     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
1792     if (flat->isa_instptr()) {
1793       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1794           && flat->is_instptr()->klass() == env()->Class_klass())
1795         alias_type(idx)->set_rewritable(false);
1796     }
1797     ciField* field = NULL;
1798     if (flat->isa_aryptr()) {
1799 #ifdef ASSERT
1800       const int header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1801       // (T_BYTE has the weakest alignment and size restrictions...)
1802       assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
1803 #endif
1804       const Type* elemtype = flat->is_aryptr()->elem();
1805       if (flat->offset() == TypePtr::OffsetBot) {
1806         alias_type(idx)->set_element(elemtype);
1807       }
1808       int field_offset = flat->is_aryptr()->field_offset().get();
1809       if (elemtype->isa_valuetype() && field_offset != Type::OffsetBot) {
1810         ciValueKlass* vk = elemtype->is_valuetype()->value_klass();
1811         field_offset += vk->first_field_offset();
1812         field = vk->get_field_by_offset(field_offset, false);
1813       }
1814     }
1815     if (flat->isa_klassptr()) {
1816       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1817         alias_type(idx)->set_rewritable(false);
1818       if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
1819         alias_type(idx)->set_rewritable(false);
1820       if (flat->offset() == in_bytes(Klass::access_flags_offset()))
1821         alias_type(idx)->set_rewritable(false);
1822       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1823         alias_type(idx)->set_rewritable(false);
1824     }
1825     // %%% (We would like to finalize JavaThread::threadObj_offset(),
1826     // but the base pointer type is not distinctive enough to identify
1827     // references into JavaThread.)
1828 
1829     // Check for final fields.
1830     const TypeInstPtr* tinst = flat->isa_instptr();
1831     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1832       if (tinst->const_oop() != NULL &&
1833           tinst->klass() == ciEnv::current()->Class_klass() &&
1834           tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
1835         // static field
1836         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1837         field = k->get_field_by_offset(tinst->offset(), true);
1838       } else if (tinst->klass()->is_valuetype()) {
1839         // Value type field
1840         ciValueKlass* vk = tinst->value_klass();
1841         field = vk->get_field_by_offset(tinst->offset(), false);
1842       } else {
1843         ciInstanceKlass* k = tinst->klass()->as_instance_klass();
1844         field = k->get_field_by_offset(tinst->offset(), false);
1845       }
1846     }
1847     assert(field == NULL ||
1848            original_field == NULL ||
1849            (field->holder() == original_field->holder() &&
1850             field->offset() == original_field->offset() &&
1851             field->is_static() == original_field->is_static()), "wrong field?");
1852     // Set field() and is_rewritable() attributes.
1853     if (field != NULL)  alias_type(idx)->set_field(field);
1854   }
1855 
1856   // Fill the cache for next time.
1857   ace->_adr_type = adr_type;
1858   ace->_index    = idx;
1859   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
1860 
1861   // Might as well try to fill the cache for the flattened version, too.
1862   AliasCacheEntry* face = probe_alias_cache(flat);
1863   if (face->_adr_type == NULL) {
1864     face->_adr_type = flat;
1865     face->_index    = idx;
1866     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1867   }
1868 
1869   return alias_type(idx);
1870 }
1871 
1872 
1873 Compile::AliasType* Compile::alias_type(ciField* field) {
1874   const TypeOopPtr* t;
1875   if (field->is_static())
1876     t = TypeInstPtr::make(field->holder()->java_mirror());
1877   else
1878     t = TypeOopPtr::make_from_klass_raw(field->holder());
1879   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1880   assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
1881   return atp;
1882 }
1883 
1884 
1885 //------------------------------have_alias_type--------------------------------
1886 bool Compile::have_alias_type(const TypePtr* adr_type) {
1887   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1888   if (ace->_adr_type == adr_type) {
1889     return true;
1890   }
1891 
1892   // Handle special cases.
1893   if (adr_type == NULL)             return true;
1894   if (adr_type == TypePtr::BOTTOM)  return true;
1895 
1896   return find_alias_type(adr_type, true, NULL) != NULL;
1897 }
1898 
1899 //-----------------------------must_alias--------------------------------------
1900 // True if all values of the given address type are in the given alias category.
1901 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1902   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1903   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
1904   if (alias_idx == AliasIdxTop)         return false; // the empty category
1905   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1906 
1907   // the only remaining possible overlap is identity
1908   int adr_idx = get_alias_index(adr_type);
1909   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1910   assert(adr_idx == alias_idx ||
1911          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1912           && adr_type                       != TypeOopPtr::BOTTOM),
1913          "should not be testing for overlap with an unsafe pointer");
1914   return adr_idx == alias_idx;
1915 }
1916 
1917 //------------------------------can_alias--------------------------------------
1918 // True if any values of the given address type are in the given alias category.
1919 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1920   if (alias_idx == AliasIdxTop)         return false; // the empty category
1921   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
1922   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1923   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
1924 
1925   // the only remaining possible overlap is identity
1926   int adr_idx = get_alias_index(adr_type);
1927   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1928   return adr_idx == alias_idx;
1929 }
1930 
1931 
1932 
1933 //---------------------------pop_warm_call-------------------------------------
1934 WarmCallInfo* Compile::pop_warm_call() {
1935   WarmCallInfo* wci = _warm_calls;
1936   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
1937   return wci;
1938 }
1939 
1940 //----------------------------Inline_Warm--------------------------------------
1941 int Compile::Inline_Warm() {
1942   // If there is room, try to inline some more warm call sites.
1943   // %%% Do a graph index compaction pass when we think we're out of space?
1944   if (!InlineWarmCalls)  return 0;
1945 
1946   int calls_made_hot = 0;
1947   int room_to_grow   = NodeCountInliningCutoff - unique();
1948   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1949   int amount_grown   = 0;
1950   WarmCallInfo* call;
1951   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1952     int est_size = (int)call->size();
1953     if (est_size > (room_to_grow - amount_grown)) {
1954       // This one won't fit anyway.  Get rid of it.
1955       call->make_cold();
1956       continue;
1957     }
1958     call->make_hot();
1959     calls_made_hot++;
1960     amount_grown   += est_size;
1961     amount_to_grow -= est_size;
1962   }
1963 
1964   if (calls_made_hot > 0)  set_major_progress();
1965   return calls_made_hot;
1966 }
1967 
1968 
1969 //----------------------------Finish_Warm--------------------------------------
1970 void Compile::Finish_Warm() {
1971   if (!InlineWarmCalls)  return;
1972   if (failing())  return;
1973   if (warm_calls() == NULL)  return;
1974 
1975   // Clean up loose ends, if we are out of space for inlining.
1976   WarmCallInfo* call;
1977   while ((call = pop_warm_call()) != NULL) {
1978     call->make_cold();
1979   }
1980 }
1981 
1982 //---------------------cleanup_loop_predicates-----------------------
1983 // Remove the opaque nodes that protect the predicates so that all unused
1984 // checks and uncommon_traps will be eliminated from the ideal graph
1985 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1986   if (predicate_count()==0) return;
1987   for (int i = predicate_count(); i > 0; i--) {
1988     Node * n = predicate_opaque1_node(i-1);
1989     assert(n->Opcode() == Op_Opaque1, "must be");
1990     igvn.replace_node(n, n->in(1));
1991   }
1992   assert(predicate_count()==0, "should be clean!");
1993 }
1994 
1995 void Compile::add_range_check_cast(Node* n) {
1996   assert(n->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1997   assert(!_range_check_casts->contains(n), "duplicate entry in range check casts");
1998   _range_check_casts->append(n);
1999 }
2000 
2001 // Remove all range check dependent CastIINodes.
2002 void Compile::remove_range_check_casts(PhaseIterGVN &igvn) {
2003   for (int i = range_check_cast_count(); i > 0; i--) {
2004     Node* cast = range_check_cast_node(i-1);
2005     assert(cast->isa_CastII()->has_range_check(), "CastII should have range check dependency");
2006     igvn.replace_node(cast, cast->in(1));
2007   }
2008   assert(range_check_cast_count() == 0, "should be empty");
2009 }
2010 
2011 void Compile::add_opaque4_node(Node* n) {
2012   assert(n->Opcode() == Op_Opaque4, "Opaque4 only");
2013   assert(!_opaque4_nodes->contains(n), "duplicate entry in Opaque4 list");
2014   _opaque4_nodes->append(n);
2015 }
2016 
2017 // Remove all Opaque4 nodes.
2018 void Compile::remove_opaque4_nodes(PhaseIterGVN &igvn) {
2019   for (int i = opaque4_count(); i > 0; i--) {
2020     Node* opaq = opaque4_node(i-1);
2021     assert(opaq->Opcode() == Op_Opaque4, "Opaque4 only");
2022     igvn.replace_node(opaq, opaq->in(2));
2023   }
2024   assert(opaque4_count() == 0, "should be empty");
2025 }
2026 
2027 void Compile::add_value_type(Node* n) {
2028   assert(n->is_ValueTypeBase(), "unexpected node");
2029   if (_value_type_nodes != NULL) {
2030     _value_type_nodes->push(n);
2031   }
2032 }
2033 
2034 void Compile::remove_value_type(Node* n) {
2035   assert(n->is_ValueTypeBase(), "unexpected node");
2036   if (_value_type_nodes != NULL) {
2037     _value_type_nodes->remove(n);
2038   }
2039 }
2040 
2041 void Compile::process_value_types(PhaseIterGVN &igvn) {
2042   // Make value types scalar in safepoints
2043   while (_value_type_nodes->size() != 0) {
2044     ValueTypeBaseNode* vt = _value_type_nodes->pop()->as_ValueTypeBase();
2045     vt->make_scalar_in_safepoints(igvn.C->root(), &igvn);
2046     if (vt->is_ValueTypePtr()) {
2047       igvn.replace_node(vt, vt->get_oop());
2048     }
2049   }
2050   _value_type_nodes = NULL;
2051   igvn.optimize();
2052 }
2053 
2054 // StringOpts and late inlining of string methods
2055 void Compile::inline_string_calls(bool parse_time) {
2056   {
2057     // remove useless nodes to make the usage analysis simpler
2058     ResourceMark rm;
2059     PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2060   }
2061 
2062   {
2063     ResourceMark rm;
2064     print_method(PHASE_BEFORE_STRINGOPTS, 3);
2065     PhaseStringOpts pso(initial_gvn(), for_igvn());
2066     print_method(PHASE_AFTER_STRINGOPTS, 3);
2067   }
2068 
2069   // now inline anything that we skipped the first time around
2070   if (!parse_time) {
2071     _late_inlines_pos = _late_inlines.length();
2072   }
2073 
2074   while (_string_late_inlines.length() > 0) {
2075     CallGenerator* cg = _string_late_inlines.pop();
2076     cg->do_late_inline();
2077     if (failing())  return;
2078   }
2079   _string_late_inlines.trunc_to(0);
2080 }
2081 
2082 // Late inlining of boxing methods
2083 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
2084   if (_boxing_late_inlines.length() > 0) {
2085     assert(has_boxed_value(), "inconsistent");
2086 
2087     PhaseGVN* gvn = initial_gvn();
2088     set_inlining_incrementally(true);
2089 
2090     assert( igvn._worklist.size() == 0, "should be done with igvn" );
2091     for_igvn()->clear();
2092     gvn->replace_with(&igvn);
2093 
2094     _late_inlines_pos = _late_inlines.length();
2095 
2096     while (_boxing_late_inlines.length() > 0) {
2097       CallGenerator* cg = _boxing_late_inlines.pop();
2098       cg->do_late_inline();
2099       if (failing())  return;
2100     }
2101     _boxing_late_inlines.trunc_to(0);
2102 
2103     {
2104       ResourceMark rm;
2105       PhaseRemoveUseless pru(gvn, for_igvn());
2106     }
2107 
2108     igvn = PhaseIterGVN(gvn);
2109     igvn.optimize();
2110 
2111     set_inlining_progress(false);
2112     set_inlining_incrementally(false);
2113   }
2114 }
2115 
2116 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
2117   assert(IncrementalInline, "incremental inlining should be on");
2118   PhaseGVN* gvn = initial_gvn();
2119 
2120   set_inlining_progress(false);
2121   for_igvn()->clear();
2122   gvn->replace_with(&igvn);
2123 
2124   {
2125     TracePhase tp("incrementalInline_inline", &timers[_t_incrInline_inline]);
2126     int i = 0;
2127     for (; i <_late_inlines.length() && !inlining_progress(); i++) {
2128       CallGenerator* cg = _late_inlines.at(i);
2129       _late_inlines_pos = i+1;
2130       cg->do_late_inline();
2131       if (failing())  return;
2132     }
2133     int j = 0;
2134     for (; i < _late_inlines.length(); i++, j++) {
2135       _late_inlines.at_put(j, _late_inlines.at(i));
2136     }
2137     _late_inlines.trunc_to(j);
2138   }
2139 
2140   {
2141     TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2142     ResourceMark rm;
2143     PhaseRemoveUseless pru(gvn, for_igvn());
2144   }
2145 
2146   {
2147     TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2148     igvn = PhaseIterGVN(gvn);
2149   }
2150 }
2151 
2152 // Perform incremental inlining until bound on number of live nodes is reached
2153 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
2154   TracePhase tp("incrementalInline", &timers[_t_incrInline]);
2155 
2156   PhaseGVN* gvn = initial_gvn();
2157 
2158   set_inlining_incrementally(true);
2159   set_inlining_progress(true);
2160   uint low_live_nodes = 0;
2161 
2162   while(inlining_progress() && _late_inlines.length() > 0) {
2163 
2164     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2165       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
2166         TracePhase tp("incrementalInline_ideal", &timers[_t_incrInline_ideal]);
2167         // PhaseIdealLoop is expensive so we only try it once we are
2168         // out of live nodes and we only try it again if the previous
2169         // helped got the number of nodes down significantly
2170         PhaseIdealLoop ideal_loop(igvn, LoopOptsNone);
2171         if (failing())  return;
2172         low_live_nodes = live_nodes();
2173         _major_progress = true;
2174       }
2175 
2176       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2177         break;
2178       }
2179     }
2180 
2181     inline_incrementally_one(igvn);
2182 
2183     if (failing())  return;
2184 
2185     {
2186       TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2187       igvn.optimize();
2188     }
2189 
2190     if (failing())  return;
2191   }
2192 
2193   assert( igvn._worklist.size() == 0, "should be done with igvn" );
2194 
2195   if (_string_late_inlines.length() > 0) {
2196     assert(has_stringbuilder(), "inconsistent");
2197     for_igvn()->clear();
2198     initial_gvn()->replace_with(&igvn);
2199 
2200     inline_string_calls(false);
2201 
2202     if (failing())  return;
2203 
2204     {
2205       TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2206       ResourceMark rm;
2207       PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2208     }
2209 
2210     {
2211       TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2212       igvn = PhaseIterGVN(gvn);
2213       igvn.optimize();
2214     }
2215   }
2216 
2217   set_inlining_incrementally(false);
2218 }
2219 
2220 
2221 bool Compile::optimize_loops(int& loop_opts_cnt, PhaseIterGVN& igvn, LoopOptsMode mode) {
2222   if(loop_opts_cnt > 0) {
2223     debug_only( int cnt = 0; );
2224     while(major_progress() && (loop_opts_cnt > 0)) {
2225       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2226       assert( cnt++ < 40, "infinite cycle in loop optimization" );
2227       PhaseIdealLoop ideal_loop(igvn, mode);
2228       loop_opts_cnt--;
2229       if (failing())  return false;
2230       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
2231     }
2232   }
2233   return true;
2234 }
2235 
2236 //------------------------------Optimize---------------------------------------
2237 // Given a graph, optimize it.
2238 void Compile::Optimize() {
2239   TracePhase tp("optimizer", &timers[_t_optimizer]);
2240 
2241 #ifndef PRODUCT
2242   if (_directive->BreakAtCompileOption) {
2243     BREAKPOINT;
2244   }
2245 
2246 #endif
2247 
2248 #ifdef ASSERT
2249   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2250   bs->verify_gc_barriers(this, BarrierSetC2::BeforeOptimize);
2251 #endif
2252 
2253   ResourceMark rm;
2254   int          loop_opts_cnt;
2255 
2256   print_inlining_reinit();
2257 
2258   NOT_PRODUCT( verify_graph_edges(); )
2259 
2260   print_method(PHASE_AFTER_PARSING);
2261 
2262  {
2263   // Iterative Global Value Numbering, including ideal transforms
2264   // Initialize IterGVN with types and values from parse-time GVN
2265   PhaseIterGVN igvn(initial_gvn());
2266 #ifdef ASSERT
2267   _modified_nodes = new (comp_arena()) Unique_Node_List(comp_arena());
2268 #endif
2269   {
2270     TracePhase tp("iterGVN", &timers[_t_iterGVN]);
2271     igvn.optimize();
2272   }
2273 
2274   if (failing())  return;
2275 
2276   print_method(PHASE_ITER_GVN1, 2);
2277 
2278   inline_incrementally(igvn);
2279 
2280   print_method(PHASE_INCREMENTAL_INLINE, 2);
2281 
2282   if (failing())  return;
2283 
2284   if (eliminate_boxing()) {
2285     // Inline valueOf() methods now.
2286     inline_boxing_calls(igvn);
2287 
2288     if (AlwaysIncrementalInline) {
2289       inline_incrementally(igvn);
2290     }
2291 
2292     print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
2293 
2294     if (failing())  return;
2295   }
2296 
2297   // Remove the speculative part of types and clean up the graph from
2298   // the extra CastPP nodes whose only purpose is to carry them. Do
2299   // that early so that optimizations are not disrupted by the extra
2300   // CastPP nodes.
2301   remove_speculative_types(igvn);
2302 
2303   // No more new expensive nodes will be added to the list from here
2304   // so keep only the actual candidates for optimizations.
2305   cleanup_expensive_nodes(igvn);
2306 
2307   if (!failing() && RenumberLiveNodes && live_nodes() + NodeLimitFudgeFactor < unique()) {
2308     Compile::TracePhase tp("", &timers[_t_renumberLive]);
2309     initial_gvn()->replace_with(&igvn);
2310     for_igvn()->clear();
2311     Unique_Node_List new_worklist(C->comp_arena());
2312     {
2313       ResourceMark rm;
2314       PhaseRenumberLive prl = PhaseRenumberLive(initial_gvn(), for_igvn(), &new_worklist);
2315     }
2316     set_for_igvn(&new_worklist);
2317     igvn = PhaseIterGVN(initial_gvn());
2318     igvn.optimize();
2319   }
2320 
2321   if (_value_type_nodes->size() > 0) {
2322     // Do this once all inlining is over to avoid getting inconsistent debug info
2323     process_value_types(igvn);
2324   }
2325 
2326   // Perform escape analysis
2327   if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
2328     if (has_loops()) {
2329       // Cleanup graph (remove dead nodes).
2330       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2331       PhaseIdealLoop ideal_loop(igvn, LoopOptsNone);
2332       if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
2333       if (failing())  return;
2334     }
2335     ConnectionGraph::do_analysis(this, &igvn);
2336 
2337     if (failing())  return;
2338 
2339     // Optimize out fields loads from scalar replaceable allocations.
2340     igvn.optimize();
2341     print_method(PHASE_ITER_GVN_AFTER_EA, 2);
2342 
2343     if (failing())  return;
2344 
2345     if (congraph() != NULL && macro_count() > 0) {
2346       TracePhase tp("macroEliminate", &timers[_t_macroEliminate]);
2347       PhaseMacroExpand mexp(igvn);
2348       mexp.eliminate_macro_nodes();
2349       igvn.set_delay_transform(false);
2350 
2351       igvn.optimize();
2352       print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
2353 
2354       if (failing())  return;
2355     }
2356   }
2357 
2358   // Loop transforms on the ideal graph.  Range Check Elimination,
2359   // peeling, unrolling, etc.
2360 
2361   // Set loop opts counter
2362   loop_opts_cnt = num_loop_opts();
2363   if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
2364     {
2365       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2366       PhaseIdealLoop ideal_loop(igvn, LoopOptsDefault);
2367       loop_opts_cnt--;
2368       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
2369       if (failing())  return;
2370     }
2371     // Loop opts pass if partial peeling occurred in previous pass
2372     if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
2373       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2374       PhaseIdealLoop ideal_loop(igvn, LoopOptsSkipSplitIf);
2375       loop_opts_cnt--;
2376       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
2377       if (failing())  return;
2378     }
2379     // Loop opts pass for loop-unrolling before CCP
2380     if(major_progress() && (loop_opts_cnt > 0)) {
2381       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2382       PhaseIdealLoop ideal_loop(igvn, LoopOptsSkipSplitIf);
2383       loop_opts_cnt--;
2384       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
2385     }
2386     if (!failing()) {
2387       // Verify that last round of loop opts produced a valid graph
2388       TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2389       PhaseIdealLoop::verify(igvn);
2390     }
2391   }
2392   if (failing())  return;
2393 
2394   // Conditional Constant Propagation;
2395   PhaseCCP ccp( &igvn );
2396   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
2397   {
2398     TracePhase tp("ccp", &timers[_t_ccp]);
2399     ccp.do_transform();
2400   }
2401   print_method(PHASE_CPP1, 2);
2402 
2403   assert( true, "Break here to ccp.dump_old2new_map()");
2404 
2405   // Iterative Global Value Numbering, including ideal transforms
2406   {
2407     TracePhase tp("iterGVN2", &timers[_t_iterGVN2]);
2408     igvn = ccp;
2409     igvn.optimize();
2410   }
2411 
2412   print_method(PHASE_ITER_GVN2, 2);
2413 
2414   if (failing())  return;
2415 
2416   // Loop transforms on the ideal graph.  Range Check Elimination,
2417   // peeling, unrolling, etc.
2418   if (!optimize_loops(loop_opts_cnt, igvn, LoopOptsDefault)) {
2419     return;
2420   }
2421 
2422 #if INCLUDE_ZGC
2423   if (UseZGC) {
2424     ZBarrierSetC2::find_dominating_barriers(igvn);
2425   }
2426 #endif
2427 
2428   if (failing())  return;
2429 
2430   // Ensure that major progress is now clear
2431   C->clear_major_progress();
2432 
2433   {
2434     // Verify that all previous optimizations produced a valid graph
2435     // at least to this point, even if no loop optimizations were done.
2436     TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2437     PhaseIdealLoop::verify(igvn);
2438   }
2439 
2440   if (range_check_cast_count() > 0) {
2441     // No more loop optimizations. Remove all range check dependent CastIINodes.
2442     C->remove_range_check_casts(igvn);
2443     igvn.optimize();
2444   }
2445 
2446 #ifdef ASSERT
2447   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2448   bs->verify_gc_barriers(this, BarrierSetC2::BeforeExpand);
2449 #endif
2450 
2451   {
2452     TracePhase tp("macroExpand", &timers[_t_macroExpand]);
2453     PhaseMacroExpand  mex(igvn);
2454     print_method(PHASE_BEFORE_MACRO_EXPANSION, 2);
2455     if (mex.expand_macro_nodes()) {
2456       assert(failing(), "must bail out w/ explicit message");
2457       return;
2458     }
2459   }
2460 
2461   if (opaque4_count() > 0) {
2462     C->remove_opaque4_nodes(igvn);
2463     igvn.optimize();
2464   }
2465 
2466   DEBUG_ONLY( _modified_nodes = NULL; )
2467  } // (End scope of igvn; run destructor if necessary for asserts.)
2468 
2469  process_print_inlining();
2470  // A method with only infinite loops has no edges entering loops from root
2471  {
2472    TracePhase tp("graphReshape", &timers[_t_graphReshaping]);
2473    if (final_graph_reshaping()) {
2474      assert(failing(), "must bail out w/ explicit message");
2475      return;
2476    }
2477  }
2478 
2479  print_method(PHASE_OPTIMIZE_FINISHED, 2);
2480 }
2481 
2482 //------------------------------Code_Gen---------------------------------------
2483 // Given a graph, generate code for it
2484 void Compile::Code_Gen() {
2485   if (failing()) {
2486     return;
2487   }
2488 
2489   // Perform instruction selection.  You might think we could reclaim Matcher
2490   // memory PDQ, but actually the Matcher is used in generating spill code.
2491   // Internals of the Matcher (including some VectorSets) must remain live
2492   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
2493   // set a bit in reclaimed memory.
2494 
2495   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2496   // nodes.  Mapping is only valid at the root of each matched subtree.
2497   NOT_PRODUCT( verify_graph_edges(); )
2498 
2499   Matcher matcher;
2500   _matcher = &matcher;
2501   {
2502     TracePhase tp("matcher", &timers[_t_matcher]);
2503     matcher.match();
2504   }
2505   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2506   // nodes.  Mapping is only valid at the root of each matched subtree.
2507   NOT_PRODUCT( verify_graph_edges(); )
2508 
2509   // If you have too many nodes, or if matching has failed, bail out
2510   check_node_count(0, "out of nodes matching instructions");
2511   if (failing()) {
2512     return;
2513   }
2514 
2515   print_method(PHASE_MATCHING, 2);
2516 
2517   // Build a proper-looking CFG
2518   PhaseCFG cfg(node_arena(), root(), matcher);
2519   _cfg = &cfg;
2520   {
2521     TracePhase tp("scheduler", &timers[_t_scheduler]);
2522     bool success = cfg.do_global_code_motion();
2523     if (!success) {
2524       return;
2525     }
2526 
2527     print_method(PHASE_GLOBAL_CODE_MOTION, 2);
2528     NOT_PRODUCT( verify_graph_edges(); )
2529     debug_only( cfg.verify(); )
2530   }
2531 
2532   PhaseChaitin regalloc(unique(), cfg, matcher, false);
2533   _regalloc = &regalloc;
2534   {
2535     TracePhase tp("regalloc", &timers[_t_registerAllocation]);
2536     // Perform register allocation.  After Chaitin, use-def chains are
2537     // no longer accurate (at spill code) and so must be ignored.
2538     // Node->LRG->reg mappings are still accurate.
2539     _regalloc->Register_Allocate();
2540 
2541     // Bail out if the allocator builds too many nodes
2542     if (failing()) {
2543       return;
2544     }
2545   }
2546 
2547   // Prior to register allocation we kept empty basic blocks in case the
2548   // the allocator needed a place to spill.  After register allocation we
2549   // are not adding any new instructions.  If any basic block is empty, we
2550   // can now safely remove it.
2551   {
2552     TracePhase tp("blockOrdering", &timers[_t_blockOrdering]);
2553     cfg.remove_empty_blocks();
2554     if (do_freq_based_layout()) {
2555       PhaseBlockLayout layout(cfg);
2556     } else {
2557       cfg.set_loop_alignment();
2558     }
2559     cfg.fixup_flow();
2560   }
2561 
2562   // Apply peephole optimizations
2563   if( OptoPeephole ) {
2564     TracePhase tp("peephole", &timers[_t_peephole]);
2565     PhasePeephole peep( _regalloc, cfg);
2566     peep.do_transform();
2567   }
2568 
2569   // Do late expand if CPU requires this.
2570   if (Matcher::require_postalloc_expand) {
2571     TracePhase tp("postalloc_expand", &timers[_t_postalloc_expand]);
2572     cfg.postalloc_expand(_regalloc);
2573   }
2574 
2575   // Convert Nodes to instruction bits in a buffer
2576   {
2577     TraceTime tp("output", &timers[_t_output], CITime);
2578     Output();
2579   }
2580 
2581   print_method(PHASE_FINAL_CODE);
2582 
2583   // He's dead, Jim.
2584   _cfg     = (PhaseCFG*)((intptr_t)0xdeadbeef);
2585   _regalloc = (PhaseChaitin*)((intptr_t)0xdeadbeef);
2586 }
2587 
2588 
2589 //------------------------------dump_asm---------------------------------------
2590 // Dump formatted assembly
2591 #ifndef PRODUCT
2592 void Compile::dump_asm(int *pcs, uint pc_limit) {
2593   bool cut_short = false;
2594   tty->print_cr("#");
2595   tty->print("#  ");  _tf->dump();  tty->cr();
2596   tty->print_cr("#");
2597 
2598   // For all blocks
2599   int pc = 0x0;                 // Program counter
2600   char starts_bundle = ' ';
2601   _regalloc->dump_frame();
2602 
2603   Node *n = NULL;
2604   for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
2605     if (VMThread::should_terminate()) {
2606       cut_short = true;
2607       break;
2608     }
2609     Block* block = _cfg->get_block(i);
2610     if (block->is_connector() && !Verbose) {
2611       continue;
2612     }
2613     n = block->head();
2614     if (pcs && n->_idx < pc_limit) {
2615       tty->print("%3.3x   ", pcs[n->_idx]);
2616     } else {
2617       tty->print("      ");
2618     }
2619     block->dump_head(_cfg);
2620     if (block->is_connector()) {
2621       tty->print_cr("        # Empty connector block");
2622     } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
2623       tty->print_cr("        # Block is sole successor of call");
2624     }
2625 
2626     // For all instructions
2627     Node *delay = NULL;
2628     for (uint j = 0; j < block->number_of_nodes(); j++) {
2629       if (VMThread::should_terminate()) {
2630         cut_short = true;
2631         break;
2632       }
2633       n = block->get_node(j);
2634       if (valid_bundle_info(n)) {
2635         Bundle* bundle = node_bundling(n);
2636         if (bundle->used_in_unconditional_delay()) {
2637           delay = n;
2638           continue;
2639         }
2640         if (bundle->starts_bundle()) {
2641           starts_bundle = '+';
2642         }
2643       }
2644 
2645       if (WizardMode) {
2646         n->dump();
2647       }
2648 
2649       if( !n->is_Region() &&    // Dont print in the Assembly
2650           !n->is_Phi() &&       // a few noisely useless nodes
2651           !n->is_Proj() &&
2652           !n->is_MachTemp() &&
2653           !n->is_SafePointScalarObject() &&
2654           !n->is_Catch() &&     // Would be nice to print exception table targets
2655           !n->is_MergeMem() &&  // Not very interesting
2656           !n->is_top() &&       // Debug info table constants
2657           !(n->is_Con() && !n->is_Mach())// Debug info table constants
2658           ) {
2659         if (pcs && n->_idx < pc_limit)
2660           tty->print("%3.3x", pcs[n->_idx]);
2661         else
2662           tty->print("   ");
2663         tty->print(" %c ", starts_bundle);
2664         starts_bundle = ' ';
2665         tty->print("\t");
2666         n->format(_regalloc, tty);
2667         tty->cr();
2668       }
2669 
2670       // If we have an instruction with a delay slot, and have seen a delay,
2671       // then back up and print it
2672       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
2673         assert(delay != NULL, "no unconditional delay instruction");
2674         if (WizardMode) delay->dump();
2675 
2676         if (node_bundling(delay)->starts_bundle())
2677           starts_bundle = '+';
2678         if (pcs && n->_idx < pc_limit)
2679           tty->print("%3.3x", pcs[n->_idx]);
2680         else
2681           tty->print("   ");
2682         tty->print(" %c ", starts_bundle);
2683         starts_bundle = ' ';
2684         tty->print("\t");
2685         delay->format(_regalloc, tty);
2686         tty->cr();
2687         delay = NULL;
2688       }
2689 
2690       // Dump the exception table as well
2691       if( n->is_Catch() && (Verbose || WizardMode) ) {
2692         // Print the exception table for this offset
2693         _handler_table.print_subtable_for(pc);
2694       }
2695     }
2696 
2697     if (pcs && n->_idx < pc_limit)
2698       tty->print_cr("%3.3x", pcs[n->_idx]);
2699     else
2700       tty->cr();
2701 
2702     assert(cut_short || delay == NULL, "no unconditional delay branch");
2703 
2704   } // End of per-block dump
2705   tty->cr();
2706 
2707   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
2708 }
2709 #endif
2710 
2711 //------------------------------Final_Reshape_Counts---------------------------
2712 // This class defines counters to help identify when a method
2713 // may/must be executed using hardware with only 24-bit precision.
2714 struct Final_Reshape_Counts : public StackObj {
2715   int  _call_count;             // count non-inlined 'common' calls
2716   int  _float_count;            // count float ops requiring 24-bit precision
2717   int  _double_count;           // count double ops requiring more precision
2718   int  _java_call_count;        // count non-inlined 'java' calls
2719   int  _inner_loop_count;       // count loops which need alignment
2720   VectorSet _visited;           // Visitation flags
2721   Node_List _tests;             // Set of IfNodes & PCTableNodes
2722 
2723   Final_Reshape_Counts() :
2724     _call_count(0), _float_count(0), _double_count(0),
2725     _java_call_count(0), _inner_loop_count(0),
2726     _visited( Thread::current()->resource_area() ) { }
2727 
2728   void inc_call_count  () { _call_count  ++; }
2729   void inc_float_count () { _float_count ++; }
2730   void inc_double_count() { _double_count++; }
2731   void inc_java_call_count() { _java_call_count++; }
2732   void inc_inner_loop_count() { _inner_loop_count++; }
2733 
2734   int  get_call_count  () const { return _call_count  ; }
2735   int  get_float_count () const { return _float_count ; }
2736   int  get_double_count() const { return _double_count; }
2737   int  get_java_call_count() const { return _java_call_count; }
2738   int  get_inner_loop_count() const { return _inner_loop_count; }
2739 };
2740 
2741 #ifdef ASSERT
2742 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
2743   ciInstanceKlass *k = tp->klass()->as_instance_klass();
2744   // Make sure the offset goes inside the instance layout.
2745   return k->contains_field_offset(tp->offset());
2746   // Note that OffsetBot and OffsetTop are very negative.
2747 }
2748 #endif
2749 
2750 // Eliminate trivially redundant StoreCMs and accumulate their
2751 // precedence edges.
2752 void Compile::eliminate_redundant_card_marks(Node* n) {
2753   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
2754   if (n->in(MemNode::Address)->outcnt() > 1) {
2755     // There are multiple users of the same address so it might be
2756     // possible to eliminate some of the StoreCMs
2757     Node* mem = n->in(MemNode::Memory);
2758     Node* adr = n->in(MemNode::Address);
2759     Node* val = n->in(MemNode::ValueIn);
2760     Node* prev = n;
2761     bool done = false;
2762     // Walk the chain of StoreCMs eliminating ones that match.  As
2763     // long as it's a chain of single users then the optimization is
2764     // safe.  Eliminating partially redundant StoreCMs would require
2765     // cloning copies down the other paths.
2766     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
2767       if (adr == mem->in(MemNode::Address) &&
2768           val == mem->in(MemNode::ValueIn)) {
2769         // redundant StoreCM
2770         if (mem->req() > MemNode::OopStore) {
2771           // Hasn't been processed by this code yet.
2772           n->add_prec(mem->in(MemNode::OopStore));
2773         } else {
2774           // Already converted to precedence edge
2775           for (uint i = mem->req(); i < mem->len(); i++) {
2776             // Accumulate any precedence edges
2777             if (mem->in(i) != NULL) {
2778               n->add_prec(mem->in(i));
2779             }
2780           }
2781           // Everything above this point has been processed.
2782           done = true;
2783         }
2784         // Eliminate the previous StoreCM
2785         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
2786         assert(mem->outcnt() == 0, "should be dead");
2787         mem->disconnect_inputs(NULL, this);
2788       } else {
2789         prev = mem;
2790       }
2791       mem = prev->in(MemNode::Memory);
2792     }
2793   }
2794 }
2795 
2796 
2797 //------------------------------final_graph_reshaping_impl----------------------
2798 // Implement items 1-5 from final_graph_reshaping below.
2799 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
2800 
2801   if ( n->outcnt() == 0 ) return; // dead node
2802   uint nop = n->Opcode();
2803 
2804   // Check for 2-input instruction with "last use" on right input.
2805   // Swap to left input.  Implements item (2).
2806   if( n->req() == 3 &&          // two-input instruction
2807       n->in(1)->outcnt() > 1 && // left use is NOT a last use
2808       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
2809       n->in(2)->outcnt() == 1 &&// right use IS a last use
2810       !n->in(2)->is_Con() ) {   // right use is not a constant
2811     // Check for commutative opcode
2812     switch( nop ) {
2813     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
2814     case Op_MaxI:  case Op_MinI:
2815     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
2816     case Op_AndL:  case Op_XorL:  case Op_OrL:
2817     case Op_AndI:  case Op_XorI:  case Op_OrI: {
2818       // Move "last use" input to left by swapping inputs
2819       n->swap_edges(1, 2);
2820       break;
2821     }
2822     default:
2823       break;
2824     }
2825   }
2826 
2827 #ifdef ASSERT
2828   if( n->is_Mem() ) {
2829     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
2830     assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
2831             // oop will be recorded in oop map if load crosses safepoint
2832             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
2833                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
2834             "raw memory operations should have control edge");
2835   }
2836   if (n->is_MemBar()) {
2837     MemBarNode* mb = n->as_MemBar();
2838     if (mb->trailing_store() || mb->trailing_load_store()) {
2839       assert(mb->leading_membar()->trailing_membar() == mb, "bad membar pair");
2840       Node* mem = mb->in(MemBarNode::Precedent);
2841       assert((mb->trailing_store() && mem->is_Store() && mem->as_Store()->is_release()) ||
2842              (mb->trailing_load_store() && mem->is_LoadStore()), "missing mem op");
2843     } else if (mb->leading()) {
2844       assert(mb->trailing_membar()->leading_membar() == mb, "bad membar pair");
2845     }
2846   }
2847 #endif
2848   // Count FPU ops and common calls, implements item (3)
2849   bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->final_graph_reshaping(this, n, nop);
2850   if (!gc_handled) {
2851     final_graph_reshaping_main_switch(n, frc, nop);
2852   }
2853 
2854   // Collect CFG split points
2855   if (n->is_MultiBranch() && !n->is_RangeCheck()) {
2856     frc._tests.push(n);
2857   }
2858 }
2859 
2860 void Compile::final_graph_reshaping_main_switch(Node* n, Final_Reshape_Counts& frc, uint nop) {
2861   switch( nop ) {
2862   // Count all float operations that may use FPU
2863   case Op_AddF:
2864   case Op_SubF:
2865   case Op_MulF:
2866   case Op_DivF:
2867   case Op_NegF:
2868   case Op_ModF:
2869   case Op_ConvI2F:
2870   case Op_ConF:
2871   case Op_CmpF:
2872   case Op_CmpF3:
2873   // case Op_ConvL2F: // longs are split into 32-bit halves
2874     frc.inc_float_count();
2875     break;
2876 
2877   case Op_ConvF2D:
2878   case Op_ConvD2F:
2879     frc.inc_float_count();
2880     frc.inc_double_count();
2881     break;
2882 
2883   // Count all double operations that may use FPU
2884   case Op_AddD:
2885   case Op_SubD:
2886   case Op_MulD:
2887   case Op_DivD:
2888   case Op_NegD:
2889   case Op_ModD:
2890   case Op_ConvI2D:
2891   case Op_ConvD2I:
2892   // case Op_ConvL2D: // handled by leaf call
2893   // case Op_ConvD2L: // handled by leaf call
2894   case Op_ConD:
2895   case Op_CmpD:
2896   case Op_CmpD3:
2897     frc.inc_double_count();
2898     break;
2899   case Op_Opaque1:              // Remove Opaque Nodes before matching
2900   case Op_Opaque2:              // Remove Opaque Nodes before matching
2901   case Op_Opaque3:
2902     n->subsume_by(n->in(1), this);
2903     break;
2904   case Op_CallStaticJava:
2905   case Op_CallJava:
2906   case Op_CallDynamicJava:
2907     frc.inc_java_call_count(); // Count java call site;
2908   case Op_CallRuntime:
2909   case Op_CallLeaf:
2910   case Op_CallLeafNoFP: {
2911     assert (n->is_Call(), "");
2912     CallNode *call = n->as_Call();
2913     // Count call sites where the FP mode bit would have to be flipped.
2914     // Do not count uncommon runtime calls:
2915     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
2916     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
2917     if (!call->is_CallStaticJava() || !call->as_CallStaticJava()->_name) {
2918       frc.inc_call_count();   // Count the call site
2919     } else {                  // See if uncommon argument is shared
2920       Node *n = call->in(TypeFunc::Parms);
2921       int nop = n->Opcode();
2922       // Clone shared simple arguments to uncommon calls, item (1).
2923       if (n->outcnt() > 1 &&
2924           !n->is_Proj() &&
2925           nop != Op_CreateEx &&
2926           nop != Op_CheckCastPP &&
2927           nop != Op_DecodeN &&
2928           nop != Op_DecodeNKlass &&
2929           !n->is_Mem() &&
2930           !n->is_Phi()) {
2931         Node *x = n->clone();
2932         call->set_req(TypeFunc::Parms, x);
2933       }
2934     }
2935     break;
2936   }
2937 
2938   case Op_StoreD:
2939   case Op_LoadD:
2940   case Op_LoadD_unaligned:
2941     frc.inc_double_count();
2942     goto handle_mem;
2943   case Op_StoreF:
2944   case Op_LoadF:
2945     frc.inc_float_count();
2946     goto handle_mem;
2947 
2948   case Op_StoreCM:
2949     {
2950       // Convert OopStore dependence into precedence edge
2951       Node* prec = n->in(MemNode::OopStore);
2952       n->del_req(MemNode::OopStore);
2953       n->add_prec(prec);
2954       eliminate_redundant_card_marks(n);
2955     }
2956 
2957     // fall through
2958 
2959   case Op_StoreB:
2960   case Op_StoreC:
2961   case Op_StorePConditional:
2962   case Op_StoreI:
2963   case Op_StoreL:
2964   case Op_StoreIConditional:
2965   case Op_StoreLConditional:
2966   case Op_CompareAndSwapB:
2967   case Op_CompareAndSwapS:
2968   case Op_CompareAndSwapI:
2969   case Op_CompareAndSwapL:
2970   case Op_CompareAndSwapP:
2971   case Op_CompareAndSwapN:
2972   case Op_WeakCompareAndSwapB:
2973   case Op_WeakCompareAndSwapS:
2974   case Op_WeakCompareAndSwapI:
2975   case Op_WeakCompareAndSwapL:
2976   case Op_WeakCompareAndSwapP:
2977   case Op_WeakCompareAndSwapN:
2978   case Op_CompareAndExchangeB:
2979   case Op_CompareAndExchangeS:
2980   case Op_CompareAndExchangeI:
2981   case Op_CompareAndExchangeL:
2982   case Op_CompareAndExchangeP:
2983   case Op_CompareAndExchangeN:
2984   case Op_GetAndAddS:
2985   case Op_GetAndAddB:
2986   case Op_GetAndAddI:
2987   case Op_GetAndAddL:
2988   case Op_GetAndSetS:
2989   case Op_GetAndSetB:
2990   case Op_GetAndSetI:
2991   case Op_GetAndSetL:
2992   case Op_GetAndSetP:
2993   case Op_GetAndSetN:
2994   case Op_StoreP:
2995   case Op_StoreN:
2996   case Op_StoreNKlass:
2997   case Op_LoadB:
2998   case Op_LoadUB:
2999   case Op_LoadUS:
3000   case Op_LoadI:
3001   case Op_LoadKlass:
3002   case Op_LoadNKlass:
3003   case Op_LoadL:
3004   case Op_LoadL_unaligned:
3005   case Op_LoadPLocked:
3006   case Op_LoadP:
3007   case Op_LoadN:
3008   case Op_LoadRange:
3009   case Op_LoadS: {
3010   handle_mem:
3011 #ifdef ASSERT
3012     if( VerifyOptoOopOffsets ) {
3013       MemNode* mem  = n->as_Mem();
3014       // Check to see if address types have grounded out somehow.
3015       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
3016       assert( !tp || oop_offset_is_sane(tp), "" );
3017     }
3018 #endif
3019     break;
3020   }
3021 
3022   case Op_AddP: {               // Assert sane base pointers
3023     Node *addp = n->in(AddPNode::Address);
3024     assert( !addp->is_AddP() ||
3025             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
3026             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
3027             "Base pointers must match (addp %u)", addp->_idx );
3028 #ifdef _LP64
3029     if ((UseCompressedOops || UseCompressedClassPointers) &&
3030         addp->Opcode() == Op_ConP &&
3031         addp == n->in(AddPNode::Base) &&
3032         n->in(AddPNode::Offset)->is_Con()) {
3033       // If the transformation of ConP to ConN+DecodeN is beneficial depends
3034       // on the platform and on the compressed oops mode.
3035       // Use addressing with narrow klass to load with offset on x86.
3036       // Some platforms can use the constant pool to load ConP.
3037       // Do this transformation here since IGVN will convert ConN back to ConP.
3038       const Type* t = addp->bottom_type();
3039       bool is_oop   = t->isa_oopptr() != NULL;
3040       bool is_klass = t->isa_klassptr() != NULL;
3041 
3042       if ((is_oop   && Matcher::const_oop_prefer_decode()  ) ||
3043           (is_klass && Matcher::const_klass_prefer_decode())) {
3044         Node* nn = NULL;
3045 
3046         int op = is_oop ? Op_ConN : Op_ConNKlass;
3047 
3048         // Look for existing ConN node of the same exact type.
3049         Node* r  = root();
3050         uint cnt = r->outcnt();
3051         for (uint i = 0; i < cnt; i++) {
3052           Node* m = r->raw_out(i);
3053           if (m!= NULL && m->Opcode() == op &&
3054               m->bottom_type()->make_ptr() == t) {
3055             nn = m;
3056             break;
3057           }
3058         }
3059         if (nn != NULL) {
3060           // Decode a narrow oop to match address
3061           // [R12 + narrow_oop_reg<<3 + offset]
3062           if (is_oop) {
3063             nn = new DecodeNNode(nn, t);
3064           } else {
3065             nn = new DecodeNKlassNode(nn, t);
3066           }
3067           // Check for succeeding AddP which uses the same Base.
3068           // Otherwise we will run into the assertion above when visiting that guy.
3069           for (uint i = 0; i < n->outcnt(); ++i) {
3070             Node *out_i = n->raw_out(i);
3071             if (out_i && out_i->is_AddP() && out_i->in(AddPNode::Base) == addp) {
3072               out_i->set_req(AddPNode::Base, nn);
3073 #ifdef ASSERT
3074               for (uint j = 0; j < out_i->outcnt(); ++j) {
3075                 Node *out_j = out_i->raw_out(j);
3076                 assert(out_j == NULL || !out_j->is_AddP() || out_j->in(AddPNode::Base) != addp,
3077                        "more than 2 AddP nodes in a chain (out_j %u)", out_j->_idx);
3078               }
3079 #endif
3080             }
3081           }
3082           n->set_req(AddPNode::Base, nn);
3083           n->set_req(AddPNode::Address, nn);
3084           if (addp->outcnt() == 0) {
3085             addp->disconnect_inputs(NULL, this);
3086           }
3087         }
3088       }
3089     }
3090 #endif
3091     // platform dependent reshaping of the address expression
3092     reshape_address(n->as_AddP());
3093     break;
3094   }
3095 
3096   case Op_CastPP: {
3097     // Remove CastPP nodes to gain more freedom during scheduling but
3098     // keep the dependency they encode as control or precedence edges
3099     // (if control is set already) on memory operations. Some CastPP
3100     // nodes don't have a control (don't carry a dependency): skip
3101     // those.
3102     if (n->in(0) != NULL) {
3103       ResourceMark rm;
3104       Unique_Node_List wq;
3105       wq.push(n);
3106       for (uint next = 0; next < wq.size(); ++next) {
3107         Node *m = wq.at(next);
3108         for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
3109           Node* use = m->fast_out(i);
3110           if (use->is_Mem() || use->is_EncodeNarrowPtr()) {
3111             use->ensure_control_or_add_prec(n->in(0));
3112           } else {
3113             switch(use->Opcode()) {
3114             case Op_AddP:
3115             case Op_DecodeN:
3116             case Op_DecodeNKlass:
3117             case Op_CheckCastPP:
3118             case Op_CastPP:
3119               wq.push(use);
3120               break;
3121             }
3122           }
3123         }
3124       }
3125     }
3126     const bool is_LP64 = LP64_ONLY(true) NOT_LP64(false);
3127     if (is_LP64 && n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
3128       Node* in1 = n->in(1);
3129       const Type* t = n->bottom_type();
3130       Node* new_in1 = in1->clone();
3131       new_in1->as_DecodeN()->set_type(t);
3132 
3133       if (!Matcher::narrow_oop_use_complex_address()) {
3134         //
3135         // x86, ARM and friends can handle 2 adds in addressing mode
3136         // and Matcher can fold a DecodeN node into address by using
3137         // a narrow oop directly and do implicit NULL check in address:
3138         //
3139         // [R12 + narrow_oop_reg<<3 + offset]
3140         // NullCheck narrow_oop_reg
3141         //
3142         // On other platforms (Sparc) we have to keep new DecodeN node and
3143         // use it to do implicit NULL check in address:
3144         //
3145         // decode_not_null narrow_oop_reg, base_reg
3146         // [base_reg + offset]
3147         // NullCheck base_reg
3148         //
3149         // Pin the new DecodeN node to non-null path on these platform (Sparc)
3150         // to keep the information to which NULL check the new DecodeN node
3151         // corresponds to use it as value in implicit_null_check().
3152         //
3153         new_in1->set_req(0, n->in(0));
3154       }
3155 
3156       n->subsume_by(new_in1, this);
3157       if (in1->outcnt() == 0) {
3158         in1->disconnect_inputs(NULL, this);
3159       }
3160     } else {
3161       n->subsume_by(n->in(1), this);
3162       if (n->outcnt() == 0) {
3163         n->disconnect_inputs(NULL, this);
3164       }
3165     }
3166     break;
3167   }
3168 #ifdef _LP64
3169   case Op_CmpP:
3170     // Do this transformation here to preserve CmpPNode::sub() and
3171     // other TypePtr related Ideal optimizations (for example, ptr nullness).
3172     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
3173       Node* in1 = n->in(1);
3174       Node* in2 = n->in(2);
3175       if (!in1->is_DecodeNarrowPtr()) {
3176         in2 = in1;
3177         in1 = n->in(2);
3178       }
3179       assert(in1->is_DecodeNarrowPtr(), "sanity");
3180 
3181       Node* new_in2 = NULL;
3182       if (in2->is_DecodeNarrowPtr()) {
3183         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
3184         new_in2 = in2->in(1);
3185       } else if (in2->Opcode() == Op_ConP) {
3186         const Type* t = in2->bottom_type();
3187         if (t == TypePtr::NULL_PTR) {
3188           assert(in1->is_DecodeN(), "compare klass to null?");
3189           // Don't convert CmpP null check into CmpN if compressed
3190           // oops implicit null check is not generated.
3191           // This will allow to generate normal oop implicit null check.
3192           if (Matcher::gen_narrow_oop_implicit_null_checks())
3193             new_in2 = ConNode::make(TypeNarrowOop::NULL_PTR);
3194           //
3195           // This transformation together with CastPP transformation above
3196           // will generated code for implicit NULL checks for compressed oops.
3197           //
3198           // The original code after Optimize()
3199           //
3200           //    LoadN memory, narrow_oop_reg
3201           //    decode narrow_oop_reg, base_reg
3202           //    CmpP base_reg, NULL
3203           //    CastPP base_reg // NotNull
3204           //    Load [base_reg + offset], val_reg
3205           //
3206           // after these transformations will be
3207           //
3208           //    LoadN memory, narrow_oop_reg
3209           //    CmpN narrow_oop_reg, NULL
3210           //    decode_not_null narrow_oop_reg, base_reg
3211           //    Load [base_reg + offset], val_reg
3212           //
3213           // and the uncommon path (== NULL) will use narrow_oop_reg directly
3214           // since narrow oops can be used in debug info now (see the code in
3215           // final_graph_reshaping_walk()).
3216           //
3217           // At the end the code will be matched to
3218           // on x86:
3219           //
3220           //    Load_narrow_oop memory, narrow_oop_reg
3221           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
3222           //    NullCheck narrow_oop_reg
3223           //
3224           // and on sparc:
3225           //
3226           //    Load_narrow_oop memory, narrow_oop_reg
3227           //    decode_not_null narrow_oop_reg, base_reg
3228           //    Load [base_reg + offset], val_reg
3229           //    NullCheck base_reg
3230           //
3231         } else if (t->isa_oopptr()) {
3232           new_in2 = ConNode::make(t->make_narrowoop());
3233         } else if (t->isa_klassptr()) {
3234           new_in2 = ConNode::make(t->make_narrowklass());
3235         }
3236       }
3237       if (new_in2 != NULL) {
3238         Node* cmpN = new CmpNNode(in1->in(1), new_in2);
3239         n->subsume_by(cmpN, this);
3240         if (in1->outcnt() == 0) {
3241           in1->disconnect_inputs(NULL, this);
3242         }
3243         if (in2->outcnt() == 0) {
3244           in2->disconnect_inputs(NULL, this);
3245         }
3246       }
3247     }
3248     break;
3249 
3250   case Op_DecodeN:
3251   case Op_DecodeNKlass:
3252     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
3253     // DecodeN could be pinned when it can't be fold into
3254     // an address expression, see the code for Op_CastPP above.
3255     assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
3256     break;
3257 
3258   case Op_EncodeP:
3259   case Op_EncodePKlass: {
3260     Node* in1 = n->in(1);
3261     if (in1->is_DecodeNarrowPtr()) {
3262       n->subsume_by(in1->in(1), this);
3263     } else if (in1->Opcode() == Op_ConP) {
3264       const Type* t = in1->bottom_type();
3265       if (t == TypePtr::NULL_PTR) {
3266         assert(t->isa_oopptr(), "null klass?");
3267         n->subsume_by(ConNode::make(TypeNarrowOop::NULL_PTR), this);
3268       } else if (t->isa_oopptr()) {
3269         n->subsume_by(ConNode::make(t->make_narrowoop()), this);
3270       } else if (t->isa_klassptr()) {
3271         n->subsume_by(ConNode::make(t->make_narrowklass()), this);
3272       }
3273     }
3274     if (in1->outcnt() == 0) {
3275       in1->disconnect_inputs(NULL, this);
3276     }
3277     break;
3278   }
3279 
3280   case Op_Proj: {
3281     if (OptimizeStringConcat) {
3282       ProjNode* p = n->as_Proj();
3283       if (p->_is_io_use) {
3284         // Separate projections were used for the exception path which
3285         // are normally removed by a late inline.  If it wasn't inlined
3286         // then they will hang around and should just be replaced with
3287         // the original one.
3288         Node* proj = NULL;
3289         // Replace with just one
3290         for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
3291           Node *use = i.get();
3292           if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
3293             proj = use;
3294             break;
3295           }
3296         }
3297         assert(proj != NULL, "must be found");
3298         p->subsume_by(proj, this);
3299       }
3300     }
3301     break;
3302   }
3303 
3304   case Op_Phi:
3305     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
3306       // The EncodeP optimization may create Phi with the same edges
3307       // for all paths. It is not handled well by Register Allocator.
3308       Node* unique_in = n->in(1);
3309       assert(unique_in != NULL, "");
3310       uint cnt = n->req();
3311       for (uint i = 2; i < cnt; i++) {
3312         Node* m = n->in(i);
3313         assert(m != NULL, "");
3314         if (unique_in != m)
3315           unique_in = NULL;
3316       }
3317       if (unique_in != NULL) {
3318         n->subsume_by(unique_in, this);
3319       }
3320     }
3321     break;
3322 
3323 #endif
3324 
3325 #ifdef ASSERT
3326   case Op_CastII:
3327     // Verify that all range check dependent CastII nodes were removed.
3328     if (n->isa_CastII()->has_range_check()) {
3329       n->dump(3);
3330       assert(false, "Range check dependent CastII node was not removed");
3331     }
3332     break;
3333 #endif
3334 
3335   case Op_ModI:
3336     if (UseDivMod) {
3337       // Check if a%b and a/b both exist
3338       Node* d = n->find_similar(Op_DivI);
3339       if (d) {
3340         // Replace them with a fused divmod if supported
3341         if (Matcher::has_match_rule(Op_DivModI)) {
3342           DivModINode* divmod = DivModINode::make(n);
3343           d->subsume_by(divmod->div_proj(), this);
3344           n->subsume_by(divmod->mod_proj(), this);
3345         } else {
3346           // replace a%b with a-((a/b)*b)
3347           Node* mult = new MulINode(d, d->in(2));
3348           Node* sub  = new SubINode(d->in(1), mult);
3349           n->subsume_by(sub, this);
3350         }
3351       }
3352     }
3353     break;
3354 
3355   case Op_ModL:
3356     if (UseDivMod) {
3357       // Check if a%b and a/b both exist
3358       Node* d = n->find_similar(Op_DivL);
3359       if (d) {
3360         // Replace them with a fused divmod if supported
3361         if (Matcher::has_match_rule(Op_DivModL)) {
3362           DivModLNode* divmod = DivModLNode::make(n);
3363           d->subsume_by(divmod->div_proj(), this);
3364           n->subsume_by(divmod->mod_proj(), this);
3365         } else {
3366           // replace a%b with a-((a/b)*b)
3367           Node* mult = new MulLNode(d, d->in(2));
3368           Node* sub  = new SubLNode(d->in(1), mult);
3369           n->subsume_by(sub, this);
3370         }
3371       }
3372     }
3373     break;
3374 
3375   case Op_LoadVector:
3376   case Op_StoreVector:
3377     break;
3378 
3379   case Op_AddReductionVI:
3380   case Op_AddReductionVL:
3381   case Op_AddReductionVF:
3382   case Op_AddReductionVD:
3383   case Op_MulReductionVI:
3384   case Op_MulReductionVL:
3385   case Op_MulReductionVF:
3386   case Op_MulReductionVD:
3387     break;
3388 
3389   case Op_PackB:
3390   case Op_PackS:
3391   case Op_PackI:
3392   case Op_PackF:
3393   case Op_PackL:
3394   case Op_PackD:
3395     if (n->req()-1 > 2) {
3396       // Replace many operand PackNodes with a binary tree for matching
3397       PackNode* p = (PackNode*) n;
3398       Node* btp = p->binary_tree_pack(1, n->req());
3399       n->subsume_by(btp, this);
3400     }
3401     break;
3402   case Op_Loop:
3403   case Op_CountedLoop:
3404   case Op_OuterStripMinedLoop:
3405     if (n->as_Loop()->is_inner_loop()) {
3406       frc.inc_inner_loop_count();
3407     }
3408     n->as_Loop()->verify_strip_mined(0);
3409     break;
3410   case Op_LShiftI:
3411   case Op_RShiftI:
3412   case Op_URShiftI:
3413   case Op_LShiftL:
3414   case Op_RShiftL:
3415   case Op_URShiftL:
3416     if (Matcher::need_masked_shift_count) {
3417       // The cpu's shift instructions don't restrict the count to the
3418       // lower 5/6 bits. We need to do the masking ourselves.
3419       Node* in2 = n->in(2);
3420       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
3421       const TypeInt* t = in2->find_int_type();
3422       if (t != NULL && t->is_con()) {
3423         juint shift = t->get_con();
3424         if (shift > mask) { // Unsigned cmp
3425           n->set_req(2, ConNode::make(TypeInt::make(shift & mask)));
3426         }
3427       } else {
3428         if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
3429           Node* shift = new AndINode(in2, ConNode::make(TypeInt::make(mask)));
3430           n->set_req(2, shift);
3431         }
3432       }
3433       if (in2->outcnt() == 0) { // Remove dead node
3434         in2->disconnect_inputs(NULL, this);
3435       }
3436     }
3437     break;
3438   case Op_MemBarStoreStore:
3439   case Op_MemBarRelease:
3440     // Break the link with AllocateNode: it is no longer useful and
3441     // confuses register allocation.
3442     if (n->req() > MemBarNode::Precedent) {
3443       n->set_req(MemBarNode::Precedent, top());
3444     }
3445     break;
3446   case Op_MemBarAcquire: {
3447     if (n->as_MemBar()->trailing_load() && n->req() > MemBarNode::Precedent) {
3448       // At parse time, the trailing MemBarAcquire for a volatile load
3449       // is created with an edge to the load. After optimizations,
3450       // that input may be a chain of Phis. If those phis have no
3451       // other use, then the MemBarAcquire keeps them alive and
3452       // register allocation can be confused.
3453       ResourceMark rm;
3454       Unique_Node_List wq;
3455       wq.push(n->in(MemBarNode::Precedent));
3456       n->set_req(MemBarNode::Precedent, top());
3457       while (wq.size() > 0) {
3458         Node* m = wq.pop();
3459         if (m->outcnt() == 0) {
3460           for (uint j = 0; j < m->req(); j++) {
3461             Node* in = m->in(j);
3462             if (in != NULL) {
3463               wq.push(in);
3464             }
3465           }
3466           m->disconnect_inputs(NULL, this);
3467         }
3468       }
3469     }
3470     break;
3471   }
3472   case Op_RangeCheck: {
3473     RangeCheckNode* rc = n->as_RangeCheck();
3474     Node* iff = new IfNode(rc->in(0), rc->in(1), rc->_prob, rc->_fcnt);
3475     n->subsume_by(iff, this);
3476     frc._tests.push(iff);
3477     break;
3478   }
3479   case Op_ConvI2L: {
3480     if (!Matcher::convi2l_type_required) {
3481       // Code generation on some platforms doesn't need accurate
3482       // ConvI2L types. Widening the type can help remove redundant
3483       // address computations.
3484       n->as_Type()->set_type(TypeLong::INT);
3485       ResourceMark rm;
3486       Node_List wq;
3487       wq.push(n);
3488       for (uint next = 0; next < wq.size(); next++) {
3489         Node *m = wq.at(next);
3490 
3491         for(;;) {
3492           // Loop over all nodes with identical inputs edges as m
3493           Node* k = m->find_similar(m->Opcode());
3494           if (k == NULL) {
3495             break;
3496           }
3497           // Push their uses so we get a chance to remove node made
3498           // redundant
3499           for (DUIterator_Fast imax, i = k->fast_outs(imax); i < imax; i++) {
3500             Node* u = k->fast_out(i);
3501             assert(!wq.contains(u), "shouldn't process one node several times");
3502             if (u->Opcode() == Op_LShiftL ||
3503                 u->Opcode() == Op_AddL ||
3504                 u->Opcode() == Op_SubL ||
3505                 u->Opcode() == Op_AddP) {
3506               wq.push(u);
3507             }
3508           }
3509           // Replace all nodes with identical edges as m with m
3510           k->subsume_by(m, this);
3511         }
3512       }
3513     }
3514     break;
3515   }
3516   case Op_CmpUL: {
3517     if (!Matcher::has_match_rule(Op_CmpUL)) {
3518       // We don't support unsigned long comparisons. Set 'max_idx_expr'
3519       // to max_julong if < 0 to make the signed comparison fail.
3520       ConINode* sign_pos = new ConINode(TypeInt::make(BitsPerLong - 1));
3521       Node* sign_bit_mask = new RShiftLNode(n->in(1), sign_pos);
3522       Node* orl = new OrLNode(n->in(1), sign_bit_mask);
3523       ConLNode* remove_sign_mask = new ConLNode(TypeLong::make(max_jlong));
3524       Node* andl = new AndLNode(orl, remove_sign_mask);
3525       Node* cmp = new CmpLNode(andl, n->in(2));
3526       n->subsume_by(cmp, this);
3527     }
3528     break;
3529   }
3530 #ifdef ASSERT
3531   case Op_ValueTypePtr:
3532   case Op_ValueType: {
3533     n->dump(-1);
3534     assert(false, "value type node was not removed");
3535     break;
3536   }
3537 #endif
3538   default:
3539     assert(!n->is_Call(), "");
3540     assert(!n->is_Mem(), "");
3541     assert(nop != Op_ProfileBoolean, "should be eliminated during IGVN");
3542     break;
3543   }
3544 }
3545 
3546 //------------------------------final_graph_reshaping_walk---------------------
3547 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
3548 // requires that the walk visits a node's inputs before visiting the node.
3549 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
3550   ResourceArea *area = Thread::current()->resource_area();
3551   Unique_Node_List sfpt(area);
3552 
3553   frc._visited.set(root->_idx); // first, mark node as visited
3554   uint cnt = root->req();
3555   Node *n = root;
3556   uint  i = 0;
3557   while (true) {
3558     if (i < cnt) {
3559       // Place all non-visited non-null inputs onto stack
3560       Node* m = n->in(i);
3561       ++i;
3562       if (m != NULL && !frc._visited.test_set(m->_idx)) {
3563         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL) {
3564           // compute worst case interpreter size in case of a deoptimization
3565           update_interpreter_frame_size(m->as_SafePoint()->jvms()->interpreter_frame_size());
3566 
3567           sfpt.push(m);
3568         }
3569         cnt = m->req();
3570         nstack.push(n, i); // put on stack parent and next input's index
3571         n = m;
3572         i = 0;
3573       }
3574     } else {
3575       // Now do post-visit work
3576       final_graph_reshaping_impl( n, frc );
3577       if (nstack.is_empty())
3578         break;             // finished
3579       n = nstack.node();   // Get node from stack
3580       cnt = n->req();
3581       i = nstack.index();
3582       nstack.pop();        // Shift to the next node on stack
3583     }
3584   }
3585 
3586   // Skip next transformation if compressed oops are not used.
3587   if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
3588       (!UseCompressedOops && !UseCompressedClassPointers))
3589     return;
3590 
3591   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
3592   // It could be done for an uncommon traps or any safepoints/calls
3593   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
3594   while (sfpt.size() > 0) {
3595     n = sfpt.pop();
3596     JVMState *jvms = n->as_SafePoint()->jvms();
3597     assert(jvms != NULL, "sanity");
3598     int start = jvms->debug_start();
3599     int end   = n->req();
3600     bool is_uncommon = (n->is_CallStaticJava() &&
3601                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
3602     for (int j = start; j < end; j++) {
3603       Node* in = n->in(j);
3604       if (in->is_DecodeNarrowPtr()) {
3605         bool safe_to_skip = true;
3606         if (!is_uncommon ) {
3607           // Is it safe to skip?
3608           for (uint i = 0; i < in->outcnt(); i++) {
3609             Node* u = in->raw_out(i);
3610             if (!u->is_SafePoint() ||
3611                 (u->is_Call() && u->as_Call()->has_non_debug_use(n))) {
3612               safe_to_skip = false;
3613             }
3614           }
3615         }
3616         if (safe_to_skip) {
3617           n->set_req(j, in->in(1));
3618         }
3619         if (in->outcnt() == 0) {
3620           in->disconnect_inputs(NULL, this);
3621         }
3622       }
3623     }
3624   }
3625 }
3626 
3627 //------------------------------final_graph_reshaping--------------------------
3628 // Final Graph Reshaping.
3629 //
3630 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
3631 //     and not commoned up and forced early.  Must come after regular
3632 //     optimizations to avoid GVN undoing the cloning.  Clone constant
3633 //     inputs to Loop Phis; these will be split by the allocator anyways.
3634 //     Remove Opaque nodes.
3635 // (2) Move last-uses by commutative operations to the left input to encourage
3636 //     Intel update-in-place two-address operations and better register usage
3637 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
3638 //     calls canonicalizing them back.
3639 // (3) Count the number of double-precision FP ops, single-precision FP ops
3640 //     and call sites.  On Intel, we can get correct rounding either by
3641 //     forcing singles to memory (requires extra stores and loads after each
3642 //     FP bytecode) or we can set a rounding mode bit (requires setting and
3643 //     clearing the mode bit around call sites).  The mode bit is only used
3644 //     if the relative frequency of single FP ops to calls is low enough.
3645 //     This is a key transform for SPEC mpeg_audio.
3646 // (4) Detect infinite loops; blobs of code reachable from above but not
3647 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
3648 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
3649 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
3650 //     Detection is by looking for IfNodes where only 1 projection is
3651 //     reachable from below or CatchNodes missing some targets.
3652 // (5) Assert for insane oop offsets in debug mode.
3653 
3654 bool Compile::final_graph_reshaping() {
3655   // an infinite loop may have been eliminated by the optimizer,
3656   // in which case the graph will be empty.
3657   if (root()->req() == 1) {
3658     record_method_not_compilable("trivial infinite loop");
3659     return true;
3660   }
3661 
3662   // Expensive nodes have their control input set to prevent the GVN
3663   // from freely commoning them. There's no GVN beyond this point so
3664   // no need to keep the control input. We want the expensive nodes to
3665   // be freely moved to the least frequent code path by gcm.
3666   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
3667   for (int i = 0; i < expensive_count(); i++) {
3668     _expensive_nodes->at(i)->set_req(0, NULL);
3669   }
3670 
3671   Final_Reshape_Counts frc;
3672 
3673   // Visit everybody reachable!
3674   // Allocate stack of size C->live_nodes()/2 to avoid frequent realloc
3675   Node_Stack nstack(live_nodes() >> 1);
3676   final_graph_reshaping_walk(nstack, root(), frc);
3677 
3678   // Check for unreachable (from below) code (i.e., infinite loops).
3679   for( uint i = 0; i < frc._tests.size(); i++ ) {
3680     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
3681     // Get number of CFG targets.
3682     // Note that PCTables include exception targets after calls.
3683     uint required_outcnt = n->required_outcnt();
3684     if (n->outcnt() != required_outcnt) {
3685       // Check for a few special cases.  Rethrow Nodes never take the
3686       // 'fall-thru' path, so expected kids is 1 less.
3687       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
3688         if (n->in(0)->in(0)->is_Call()) {
3689           CallNode *call = n->in(0)->in(0)->as_Call();
3690           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
3691             required_outcnt--;      // Rethrow always has 1 less kid
3692           } else if (call->req() > TypeFunc::Parms &&
3693                      call->is_CallDynamicJava()) {
3694             // Check for null receiver. In such case, the optimizer has
3695             // detected that the virtual call will always result in a null
3696             // pointer exception. The fall-through projection of this CatchNode
3697             // will not be populated.
3698             Node *arg0 = call->in(TypeFunc::Parms);
3699             if (arg0->is_Type() &&
3700                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
3701               required_outcnt--;
3702             }
3703           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
3704                      call->req() > TypeFunc::Parms+1 &&
3705                      call->is_CallStaticJava()) {
3706             // Check for negative array length. In such case, the optimizer has
3707             // detected that the allocation attempt will always result in an
3708             // exception. There is no fall-through projection of this CatchNode .
3709             Node *arg1 = call->in(TypeFunc::Parms+1);
3710             if (arg1->is_Type() &&
3711                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
3712               required_outcnt--;
3713             }
3714           }
3715         }
3716       }
3717       // Recheck with a better notion of 'required_outcnt'
3718       if (n->outcnt() != required_outcnt) {
3719         record_method_not_compilable("malformed control flow");
3720         return true;            // Not all targets reachable!
3721       }
3722     }
3723     // Check that I actually visited all kids.  Unreached kids
3724     // must be infinite loops.
3725     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
3726       if (!frc._visited.test(n->fast_out(j)->_idx)) {
3727         record_method_not_compilable("infinite loop");
3728         return true;            // Found unvisited kid; must be unreach
3729       }
3730 
3731     // Here so verification code in final_graph_reshaping_walk()
3732     // always see an OuterStripMinedLoopEnd
3733     if (n->is_OuterStripMinedLoopEnd()) {
3734       IfNode* init_iff = n->as_If();
3735       Node* iff = new IfNode(init_iff->in(0), init_iff->in(1), init_iff->_prob, init_iff->_fcnt);
3736       n->subsume_by(iff, this);
3737     }
3738   }
3739 
3740   // If original bytecodes contained a mixture of floats and doubles
3741   // check if the optimizer has made it homogenous, item (3).
3742   if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
3743       frc.get_float_count() > 32 &&
3744       frc.get_double_count() == 0 &&
3745       (10 * frc.get_call_count() < frc.get_float_count()) ) {
3746     set_24_bit_selection_and_mode( false,  true );
3747   }
3748 
3749   set_java_calls(frc.get_java_call_count());
3750   set_inner_loops(frc.get_inner_loop_count());
3751 
3752   // No infinite loops, no reason to bail out.
3753   return false;
3754 }
3755 
3756 //-----------------------------too_many_traps----------------------------------
3757 // Report if there are too many traps at the current method and bci.
3758 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
3759 bool Compile::too_many_traps(ciMethod* method,
3760                              int bci,
3761                              Deoptimization::DeoptReason reason) {
3762   ciMethodData* md = method->method_data();
3763   if (md->is_empty()) {
3764     // Assume the trap has not occurred, or that it occurred only
3765     // because of a transient condition during start-up in the interpreter.
3766     return false;
3767   }
3768   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3769   if (md->has_trap_at(bci, m, reason) != 0) {
3770     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
3771     // Also, if there are multiple reasons, or if there is no per-BCI record,
3772     // assume the worst.
3773     if (log())
3774       log()->elem("observe trap='%s' count='%d'",
3775                   Deoptimization::trap_reason_name(reason),
3776                   md->trap_count(reason));
3777     return true;
3778   } else {
3779     // Ignore method/bci and see if there have been too many globally.
3780     return too_many_traps(reason, md);
3781   }
3782 }
3783 
3784 // Less-accurate variant which does not require a method and bci.
3785 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
3786                              ciMethodData* logmd) {
3787   if (trap_count(reason) >= Deoptimization::per_method_trap_limit(reason)) {
3788     // Too many traps globally.
3789     // Note that we use cumulative trap_count, not just md->trap_count.
3790     if (log()) {
3791       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
3792       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
3793                   Deoptimization::trap_reason_name(reason),
3794                   mcount, trap_count(reason));
3795     }
3796     return true;
3797   } else {
3798     // The coast is clear.
3799     return false;
3800   }
3801 }
3802 
3803 //--------------------------too_many_recompiles--------------------------------
3804 // Report if there are too many recompiles at the current method and bci.
3805 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
3806 // Is not eager to return true, since this will cause the compiler to use
3807 // Action_none for a trap point, to avoid too many recompilations.
3808 bool Compile::too_many_recompiles(ciMethod* method,
3809                                   int bci,
3810                                   Deoptimization::DeoptReason reason) {
3811   ciMethodData* md = method->method_data();
3812   if (md->is_empty()) {
3813     // Assume the trap has not occurred, or that it occurred only
3814     // because of a transient condition during start-up in the interpreter.
3815     return false;
3816   }
3817   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
3818   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
3819   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
3820   Deoptimization::DeoptReason per_bc_reason
3821     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
3822   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3823   if ((per_bc_reason == Deoptimization::Reason_none
3824        || md->has_trap_at(bci, m, reason) != 0)
3825       // The trap frequency measure we care about is the recompile count:
3826       && md->trap_recompiled_at(bci, m)
3827       && md->overflow_recompile_count() >= bc_cutoff) {
3828     // Do not emit a trap here if it has already caused recompilations.
3829     // Also, if there are multiple reasons, or if there is no per-BCI record,
3830     // assume the worst.
3831     if (log())
3832       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
3833                   Deoptimization::trap_reason_name(reason),
3834                   md->trap_count(reason),
3835                   md->overflow_recompile_count());
3836     return true;
3837   } else if (trap_count(reason) != 0
3838              && decompile_count() >= m_cutoff) {
3839     // Too many recompiles globally, and we have seen this sort of trap.
3840     // Use cumulative decompile_count, not just md->decompile_count.
3841     if (log())
3842       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
3843                   Deoptimization::trap_reason_name(reason),
3844                   md->trap_count(reason), trap_count(reason),
3845                   md->decompile_count(), decompile_count());
3846     return true;
3847   } else {
3848     // The coast is clear.
3849     return false;
3850   }
3851 }
3852 
3853 // Compute when not to trap. Used by matching trap based nodes and
3854 // NullCheck optimization.
3855 void Compile::set_allowed_deopt_reasons() {
3856   _allowed_reasons = 0;
3857   if (is_method_compilation()) {
3858     for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
3859       assert(rs < BitsPerInt, "recode bit map");
3860       if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
3861         _allowed_reasons |= nth_bit(rs);
3862       }
3863     }
3864   }
3865 }
3866 
3867 #ifndef PRODUCT
3868 //------------------------------verify_graph_edges---------------------------
3869 // Walk the Graph and verify that there is a one-to-one correspondence
3870 // between Use-Def edges and Def-Use edges in the graph.
3871 void Compile::verify_graph_edges(bool no_dead_code) {
3872   if (VerifyGraphEdges) {
3873     ResourceArea *area = Thread::current()->resource_area();
3874     Unique_Node_List visited(area);
3875     // Call recursive graph walk to check edges
3876     _root->verify_edges(visited);
3877     if (no_dead_code) {
3878       // Now make sure that no visited node is used by an unvisited node.
3879       bool dead_nodes = false;
3880       Unique_Node_List checked(area);
3881       while (visited.size() > 0) {
3882         Node* n = visited.pop();
3883         checked.push(n);
3884         for (uint i = 0; i < n->outcnt(); i++) {
3885           Node* use = n->raw_out(i);
3886           if (checked.member(use))  continue;  // already checked
3887           if (visited.member(use))  continue;  // already in the graph
3888           if (use->is_Con())        continue;  // a dead ConNode is OK
3889           // At this point, we have found a dead node which is DU-reachable.
3890           if (!dead_nodes) {
3891             tty->print_cr("*** Dead nodes reachable via DU edges:");
3892             dead_nodes = true;
3893           }
3894           use->dump(2);
3895           tty->print_cr("---");
3896           checked.push(use);  // No repeats; pretend it is now checked.
3897         }
3898       }
3899       assert(!dead_nodes, "using nodes must be reachable from root");
3900     }
3901   }
3902 }
3903 #endif
3904 
3905 // The Compile object keeps track of failure reasons separately from the ciEnv.
3906 // This is required because there is not quite a 1-1 relation between the
3907 // ciEnv and its compilation task and the Compile object.  Note that one
3908 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
3909 // to backtrack and retry without subsuming loads.  Other than this backtracking
3910 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
3911 // by the logic in C2Compiler.
3912 void Compile::record_failure(const char* reason) {
3913   if (log() != NULL) {
3914     log()->elem("failure reason='%s' phase='compile'", reason);
3915   }
3916   if (_failure_reason == NULL) {
3917     // Record the first failure reason.
3918     _failure_reason = reason;
3919   }
3920 
3921   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
3922     C->print_method(PHASE_FAILURE);
3923   }
3924   _root = NULL;  // flush the graph, too
3925 }
3926 
3927 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator)
3928   : TraceTime(name, accumulator, CITime, CITimeVerbose),
3929     _phase_name(name), _dolog(CITimeVerbose)
3930 {
3931   if (_dolog) {
3932     C = Compile::current();
3933     _log = C->log();
3934   } else {
3935     C = NULL;
3936     _log = NULL;
3937   }
3938   if (_log != NULL) {
3939     _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3940     _log->stamp();
3941     _log->end_head();
3942   }
3943 }
3944 
3945 Compile::TracePhase::~TracePhase() {
3946 
3947   C = Compile::current();
3948   if (_dolog) {
3949     _log = C->log();
3950   } else {
3951     _log = NULL;
3952   }
3953 
3954 #ifdef ASSERT
3955   if (PrintIdealNodeCount) {
3956     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
3957                   _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
3958   }
3959 
3960   if (VerifyIdealNodeCount) {
3961     Compile::current()->print_missing_nodes();
3962   }
3963 #endif
3964 
3965   if (_log != NULL) {
3966     _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3967   }
3968 }
3969 
3970 //=============================================================================
3971 // Two Constant's are equal when the type and the value are equal.
3972 bool Compile::Constant::operator==(const Constant& other) {
3973   if (type()          != other.type()         )  return false;
3974   if (can_be_reused() != other.can_be_reused())  return false;
3975   // For floating point values we compare the bit pattern.
3976   switch (type()) {
3977   case T_INT:
3978   case T_FLOAT:   return (_v._value.i == other._v._value.i);
3979   case T_LONG:
3980   case T_DOUBLE:  return (_v._value.j == other._v._value.j);
3981   case T_OBJECT:
3982   case T_ADDRESS: return (_v._value.l == other._v._value.l);
3983   case T_VOID:    return (_v._value.l == other._v._value.l);  // jump-table entries
3984   case T_METADATA: return (_v._metadata == other._v._metadata);
3985   default: ShouldNotReachHere(); return false;
3986   }
3987 }
3988 
3989 static int type_to_size_in_bytes(BasicType t) {
3990   switch (t) {
3991   case T_INT:     return sizeof(jint   );
3992   case T_LONG:    return sizeof(jlong  );
3993   case T_FLOAT:   return sizeof(jfloat );
3994   case T_DOUBLE:  return sizeof(jdouble);
3995   case T_METADATA: return sizeof(Metadata*);
3996     // We use T_VOID as marker for jump-table entries (labels) which
3997     // need an internal word relocation.
3998   case T_VOID:
3999   case T_ADDRESS:
4000   case T_OBJECT:  return sizeof(jobject);
4001   default:
4002     ShouldNotReachHere();
4003     return -1;
4004   }
4005 }
4006 
4007 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
4008   // sort descending
4009   if (a->freq() > b->freq())  return -1;
4010   if (a->freq() < b->freq())  return  1;
4011   return 0;
4012 }
4013 
4014 void Compile::ConstantTable::calculate_offsets_and_size() {
4015   // First, sort the array by frequencies.
4016   _constants.sort(qsort_comparator);
4017 
4018 #ifdef ASSERT
4019   // Make sure all jump-table entries were sorted to the end of the
4020   // array (they have a negative frequency).
4021   bool found_void = false;
4022   for (int i = 0; i < _constants.length(); i++) {
4023     Constant con = _constants.at(i);
4024     if (con.type() == T_VOID)
4025       found_void = true;  // jump-tables
4026     else
4027       assert(!found_void, "wrong sorting");
4028   }
4029 #endif
4030 
4031   int offset = 0;
4032   for (int i = 0; i < _constants.length(); i++) {
4033     Constant* con = _constants.adr_at(i);
4034 
4035     // Align offset for type.
4036     int typesize = type_to_size_in_bytes(con->type());
4037     offset = align_up(offset, typesize);
4038     con->set_offset(offset);   // set constant's offset
4039 
4040     if (con->type() == T_VOID) {
4041       MachConstantNode* n = (MachConstantNode*) con->get_jobject();
4042       offset = offset + typesize * n->outcnt();  // expand jump-table
4043     } else {
4044       offset = offset + typesize;
4045     }
4046   }
4047 
4048   // Align size up to the next section start (which is insts; see
4049   // CodeBuffer::align_at_start).
4050   assert(_size == -1, "already set?");
4051   _size = align_up(offset, (int)CodeEntryAlignment);
4052 }
4053 
4054 void Compile::ConstantTable::emit(CodeBuffer& cb) {
4055   MacroAssembler _masm(&cb);
4056   for (int i = 0; i < _constants.length(); i++) {
4057     Constant con = _constants.at(i);
4058     address constant_addr = NULL;
4059     switch (con.type()) {
4060     case T_INT:    constant_addr = _masm.int_constant(   con.get_jint()   ); break;
4061     case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
4062     case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
4063     case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
4064     case T_OBJECT: {
4065       jobject obj = con.get_jobject();
4066       int oop_index = _masm.oop_recorder()->find_index(obj);
4067       constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
4068       break;
4069     }
4070     case T_ADDRESS: {
4071       address addr = (address) con.get_jobject();
4072       constant_addr = _masm.address_constant(addr);
4073       break;
4074     }
4075     // We use T_VOID as marker for jump-table entries (labels) which
4076     // need an internal word relocation.
4077     case T_VOID: {
4078       MachConstantNode* n = (MachConstantNode*) con.get_jobject();
4079       // Fill the jump-table with a dummy word.  The real value is
4080       // filled in later in fill_jump_table.
4081       address dummy = (address) n;
4082       constant_addr = _masm.address_constant(dummy);
4083       // Expand jump-table
4084       for (uint i = 1; i < n->outcnt(); i++) {
4085         address temp_addr = _masm.address_constant(dummy + i);
4086         assert(temp_addr, "consts section too small");
4087       }
4088       break;
4089     }
4090     case T_METADATA: {
4091       Metadata* obj = con.get_metadata();
4092       int metadata_index = _masm.oop_recorder()->find_index(obj);
4093       constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
4094       break;
4095     }
4096     default: ShouldNotReachHere();
4097     }
4098     assert(constant_addr, "consts section too small");
4099     assert((constant_addr - _masm.code()->consts()->start()) == con.offset(),
4100             "must be: %d == %d", (int) (constant_addr - _masm.code()->consts()->start()), (int)(con.offset()));
4101   }
4102 }
4103 
4104 int Compile::ConstantTable::find_offset(Constant& con) const {
4105   int idx = _constants.find(con);
4106   guarantee(idx != -1, "constant must be in constant table");
4107   int offset = _constants.at(idx).offset();
4108   guarantee(offset != -1, "constant table not emitted yet?");
4109   return offset;
4110 }
4111 
4112 void Compile::ConstantTable::add(Constant& con) {
4113   if (con.can_be_reused()) {
4114     int idx = _constants.find(con);
4115     if (idx != -1 && _constants.at(idx).can_be_reused()) {
4116       _constants.adr_at(idx)->inc_freq(con.freq());  // increase the frequency by the current value
4117       return;
4118     }
4119   }
4120   (void) _constants.append(con);
4121 }
4122 
4123 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
4124   Block* b = Compile::current()->cfg()->get_block_for_node(n);
4125   Constant con(type, value, b->_freq);
4126   add(con);
4127   return con;
4128 }
4129 
4130 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
4131   Constant con(metadata);
4132   add(con);
4133   return con;
4134 }
4135 
4136 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
4137   jvalue value;
4138   BasicType type = oper->type()->basic_type();
4139   switch (type) {
4140   case T_LONG:    value.j = oper->constantL(); break;
4141   case T_FLOAT:   value.f = oper->constantF(); break;
4142   case T_DOUBLE:  value.d = oper->constantD(); break;
4143   case T_OBJECT:
4144   case T_ADDRESS: value.l = (jobject) oper->constant(); break;
4145   case T_METADATA: return add((Metadata*)oper->constant()); break;
4146   default: guarantee(false, "unhandled type: %s", type2name(type));
4147   }
4148   return add(n, type, value);
4149 }
4150 
4151 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
4152   jvalue value;
4153   // We can use the node pointer here to identify the right jump-table
4154   // as this method is called from Compile::Fill_buffer right before
4155   // the MachNodes are emitted and the jump-table is filled (means the
4156   // MachNode pointers do not change anymore).
4157   value.l = (jobject) n;
4158   Constant con(T_VOID, value, next_jump_table_freq(), false);  // Labels of a jump-table cannot be reused.
4159   add(con);
4160   return con;
4161 }
4162 
4163 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
4164   // If called from Compile::scratch_emit_size do nothing.
4165   if (Compile::current()->in_scratch_emit_size())  return;
4166 
4167   assert(labels.is_nonempty(), "must be");
4168   assert((uint) labels.length() == n->outcnt(), "must be equal: %d == %d", labels.length(), n->outcnt());
4169 
4170   // Since MachConstantNode::constant_offset() also contains
4171   // table_base_offset() we need to subtract the table_base_offset()
4172   // to get the plain offset into the constant table.
4173   int offset = n->constant_offset() - table_base_offset();
4174 
4175   MacroAssembler _masm(&cb);
4176   address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
4177 
4178   for (uint i = 0; i < n->outcnt(); i++) {
4179     address* constant_addr = &jump_table_base[i];
4180     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));
4181     *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
4182     cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
4183   }
4184 }
4185 
4186 //----------------------------static_subtype_check-----------------------------
4187 // Shortcut important common cases when superklass is exact:
4188 // (0) superklass is java.lang.Object (can occur in reflective code)
4189 // (1) subklass is already limited to a subtype of superklass => always ok
4190 // (2) subklass does not overlap with superklass => always fail
4191 // (3) superklass has NO subtypes and we can check with a simple compare.
4192 int Compile::static_subtype_check(ciKlass* superk, ciKlass* subk) {
4193   if (StressReflectiveCode || superk == NULL || subk == NULL) {
4194     return SSC_full_test;       // Let caller generate the general case.
4195   }
4196 
4197   if (superk == env()->Object_klass()) {
4198     return SSC_always_true;     // (0) this test cannot fail
4199   }
4200 
4201   ciType* superelem = superk;
4202   if (superelem->is_array_klass())
4203     superelem = superelem->as_array_klass()->base_element_type();
4204 
4205   if (!subk->is_interface()) {  // cannot trust static interface types yet
4206     if (subk->is_subtype_of(superk)) {
4207       return SSC_always_true;   // (1) false path dead; no dynamic test needed
4208     }
4209     if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
4210         !superk->is_subtype_of(subk)) {
4211       return SSC_always_false;
4212     }
4213   }
4214 
4215   // If casting to an instance klass, it must have no subtypes
4216   if (superk->is_interface()) {
4217     // Cannot trust interfaces yet.
4218     // %%% S.B. superk->nof_implementors() == 1
4219   } else if (superelem->is_instance_klass()) {
4220     ciInstanceKlass* ik = superelem->as_instance_klass();
4221     if (!ik->has_subklass() && !ik->is_interface()) {
4222       if (!ik->is_final()) {
4223         // Add a dependency if there is a chance of a later subclass.
4224         dependencies()->assert_leaf_type(ik);
4225       }
4226       return SSC_easy_test;     // (3) caller can do a simple ptr comparison
4227     }
4228   } else {
4229     // A primitive array type has no subtypes.
4230     return SSC_easy_test;       // (3) caller can do a simple ptr comparison
4231   }
4232 
4233   return SSC_full_test;
4234 }
4235 
4236 Node* Compile::conv_I2X_index(PhaseGVN* phase, Node* idx, const TypeInt* sizetype, Node* ctrl) {
4237 #ifdef _LP64
4238   // The scaled index operand to AddP must be a clean 64-bit value.
4239   // Java allows a 32-bit int to be incremented to a negative
4240   // value, which appears in a 64-bit register as a large
4241   // positive number.  Using that large positive number as an
4242   // operand in pointer arithmetic has bad consequences.
4243   // On the other hand, 32-bit overflow is rare, and the possibility
4244   // can often be excluded, if we annotate the ConvI2L node with
4245   // a type assertion that its value is known to be a small positive
4246   // number.  (The prior range check has ensured this.)
4247   // This assertion is used by ConvI2LNode::Ideal.
4248   int index_max = max_jint - 1;  // array size is max_jint, index is one less
4249   if (sizetype != NULL) index_max = sizetype->_hi - 1;
4250   const TypeInt* iidxtype = TypeInt::make(0, index_max, Type::WidenMax);
4251   idx = constrained_convI2L(phase, idx, iidxtype, ctrl);
4252 #endif
4253   return idx;
4254 }
4255 
4256 // Convert integer value to a narrowed long type dependent on ctrl (for example, a range check)
4257 Node* Compile::constrained_convI2L(PhaseGVN* phase, Node* value, const TypeInt* itype, Node* ctrl) {
4258   if (ctrl != NULL) {
4259     // Express control dependency by a CastII node with a narrow type.
4260     value = new CastIINode(value, itype, false, true /* range check dependency */);
4261     // Make the CastII node dependent on the control input to prevent the narrowed ConvI2L
4262     // node from floating above the range check during loop optimizations. Otherwise, the
4263     // ConvI2L node may be eliminated independently of the range check, causing the data path
4264     // to become TOP while the control path is still there (although it's unreachable).
4265     value->set_req(0, ctrl);
4266     // Save CastII node to remove it after loop optimizations.
4267     phase->C->add_range_check_cast(value);
4268     value = phase->transform(value);
4269   }
4270   const TypeLong* ltype = TypeLong::make(itype->_lo, itype->_hi, itype->_widen);
4271   return phase->transform(new ConvI2LNode(value, ltype));
4272 }
4273 
4274 // The message about the current inlining is accumulated in
4275 // _print_inlining_stream and transfered into the _print_inlining_list
4276 // once we know whether inlining succeeds or not. For regular
4277 // inlining, messages are appended to the buffer pointed by
4278 // _print_inlining_idx in the _print_inlining_list. For late inlining,
4279 // a new buffer is added after _print_inlining_idx in the list. This
4280 // way we can update the inlining message for late inlining call site
4281 // when the inlining is attempted again.
4282 void Compile::print_inlining_init() {
4283   if (print_inlining() || print_intrinsics()) {
4284     _print_inlining_stream = new stringStream();
4285     _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
4286   }
4287 }
4288 
4289 void Compile::print_inlining_reinit() {
4290   if (print_inlining() || print_intrinsics()) {
4291     // Re allocate buffer when we change ResourceMark
4292     _print_inlining_stream = new stringStream();
4293   }
4294 }
4295 
4296 void Compile::print_inlining_reset() {
4297   _print_inlining_stream->reset();
4298 }
4299 
4300 void Compile::print_inlining_commit() {
4301   assert(print_inlining() || print_intrinsics(), "PrintInlining off?");
4302   // Transfer the message from _print_inlining_stream to the current
4303   // _print_inlining_list buffer and clear _print_inlining_stream.
4304   _print_inlining_list->at(_print_inlining_idx).ss()->write(_print_inlining_stream->as_string(), _print_inlining_stream->size());
4305   print_inlining_reset();
4306 }
4307 
4308 void Compile::print_inlining_push() {
4309   // Add new buffer to the _print_inlining_list at current position
4310   _print_inlining_idx++;
4311   _print_inlining_list->insert_before(_print_inlining_idx, PrintInliningBuffer());
4312 }
4313 
4314 Compile::PrintInliningBuffer& Compile::print_inlining_current() {
4315   return _print_inlining_list->at(_print_inlining_idx);
4316 }
4317 
4318 void Compile::print_inlining_update(CallGenerator* cg) {
4319   if (print_inlining() || print_intrinsics()) {
4320     if (!cg->is_late_inline()) {
4321       if (print_inlining_current().cg() != NULL) {
4322         print_inlining_push();
4323       }
4324       print_inlining_commit();
4325     } else {
4326       if (print_inlining_current().cg() != cg &&
4327           (print_inlining_current().cg() != NULL ||
4328            print_inlining_current().ss()->size() != 0)) {
4329         print_inlining_push();
4330       }
4331       print_inlining_commit();
4332       print_inlining_current().set_cg(cg);
4333     }
4334   }
4335 }
4336 
4337 void Compile::print_inlining_move_to(CallGenerator* cg) {
4338   // We resume inlining at a late inlining call site. Locate the
4339   // corresponding inlining buffer so that we can update it.
4340   if (print_inlining()) {
4341     for (int i = 0; i < _print_inlining_list->length(); i++) {
4342       if (_print_inlining_list->adr_at(i)->cg() == cg) {
4343         _print_inlining_idx = i;
4344         return;
4345       }
4346     }
4347     ShouldNotReachHere();
4348   }
4349 }
4350 
4351 void Compile::print_inlining_update_delayed(CallGenerator* cg) {
4352   if (print_inlining()) {
4353     assert(_print_inlining_stream->size() > 0, "missing inlining msg");
4354     assert(print_inlining_current().cg() == cg, "wrong entry");
4355     // replace message with new message
4356     _print_inlining_list->at_put(_print_inlining_idx, PrintInliningBuffer());
4357     print_inlining_commit();
4358     print_inlining_current().set_cg(cg);
4359   }
4360 }
4361 
4362 void Compile::print_inlining_assert_ready() {
4363   assert(!_print_inlining || _print_inlining_stream->size() == 0, "loosing data");
4364 }
4365 
4366 void Compile::process_print_inlining() {
4367   bool do_print_inlining = print_inlining() || print_intrinsics();
4368   if (do_print_inlining || log() != NULL) {
4369     // Print inlining message for candidates that we couldn't inline
4370     // for lack of space
4371     for (int i = 0; i < _late_inlines.length(); i++) {
4372       CallGenerator* cg = _late_inlines.at(i);
4373       if (!cg->is_mh_late_inline()) {
4374         const char* msg = "live nodes > LiveNodeCountInliningCutoff";
4375         if (do_print_inlining) {
4376           cg->print_inlining_late(msg);
4377         }
4378         log_late_inline_failure(cg, msg);
4379       }
4380     }
4381   }
4382   if (do_print_inlining) {
4383     ResourceMark rm;
4384     stringStream ss;
4385     for (int i = 0; i < _print_inlining_list->length(); i++) {
4386       ss.print("%s", _print_inlining_list->adr_at(i)->ss()->as_string());
4387     }
4388     size_t end = ss.size();
4389     _print_inlining_output = NEW_ARENA_ARRAY(comp_arena(), char, end+1);
4390     strncpy(_print_inlining_output, ss.base(), end+1);
4391     _print_inlining_output[end] = 0;
4392   }
4393 }
4394 
4395 void Compile::dump_print_inlining() {
4396   if (_print_inlining_output != NULL) {
4397     tty->print_raw(_print_inlining_output);
4398   }
4399 }
4400 
4401 void Compile::log_late_inline(CallGenerator* cg) {
4402   if (log() != NULL) {
4403     log()->head("late_inline method='%d'  inline_id='" JLONG_FORMAT "'", log()->identify(cg->method()),
4404                 cg->unique_id());
4405     JVMState* p = cg->call_node()->jvms();
4406     while (p != NULL) {
4407       log()->elem("jvms bci='%d' method='%d'", p->bci(), log()->identify(p->method()));
4408       p = p->caller();
4409     }
4410     log()->tail("late_inline");
4411   }
4412 }
4413 
4414 void Compile::log_late_inline_failure(CallGenerator* cg, const char* msg) {
4415   log_late_inline(cg);
4416   if (log() != NULL) {
4417     log()->inline_fail(msg);
4418   }
4419 }
4420 
4421 void Compile::log_inline_id(CallGenerator* cg) {
4422   if (log() != NULL) {
4423     // The LogCompilation tool needs a unique way to identify late
4424     // inline call sites. This id must be unique for this call site in
4425     // this compilation. Try to have it unique across compilations as
4426     // well because it can be convenient when grepping through the log
4427     // file.
4428     // Distinguish OSR compilations from others in case CICountOSR is
4429     // on.
4430     jlong id = ((jlong)unique()) + (((jlong)compile_id()) << 33) + (CICountOSR && is_osr_compilation() ? ((jlong)1) << 32 : 0);
4431     cg->set_unique_id(id);
4432     log()->elem("inline_id id='" JLONG_FORMAT "'", id);
4433   }
4434 }
4435 
4436 void Compile::log_inline_failure(const char* msg) {
4437   if (C->log() != NULL) {
4438     C->log()->inline_fail(msg);
4439   }
4440 }
4441 
4442 
4443 // Dump inlining replay data to the stream.
4444 // Don't change thread state and acquire any locks.
4445 void Compile::dump_inline_data(outputStream* out) {
4446   InlineTree* inl_tree = ilt();
4447   if (inl_tree != NULL) {
4448     out->print(" inline %d", inl_tree->count());
4449     inl_tree->dump_replay_data(out);
4450   }
4451 }
4452 
4453 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
4454   if (n1->Opcode() < n2->Opcode())      return -1;
4455   else if (n1->Opcode() > n2->Opcode()) return 1;
4456 
4457   assert(n1->req() == n2->req(), "can't compare %s nodes: n1->req() = %d, n2->req() = %d", NodeClassNames[n1->Opcode()], n1->req(), n2->req());
4458   for (uint i = 1; i < n1->req(); i++) {
4459     if (n1->in(i) < n2->in(i))      return -1;
4460     else if (n1->in(i) > n2->in(i)) return 1;
4461   }
4462 
4463   return 0;
4464 }
4465 
4466 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
4467   Node* n1 = *n1p;
4468   Node* n2 = *n2p;
4469 
4470   return cmp_expensive_nodes(n1, n2);
4471 }
4472 
4473 void Compile::sort_expensive_nodes() {
4474   if (!expensive_nodes_sorted()) {
4475     _expensive_nodes->sort(cmp_expensive_nodes);
4476   }
4477 }
4478 
4479 bool Compile::expensive_nodes_sorted() const {
4480   for (int i = 1; i < _expensive_nodes->length(); i++) {
4481     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
4482       return false;
4483     }
4484   }
4485   return true;
4486 }
4487 
4488 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
4489   if (_expensive_nodes->length() == 0) {
4490     return false;
4491   }
4492 
4493   assert(OptimizeExpensiveOps, "optimization off?");
4494 
4495   // Take this opportunity to remove dead nodes from the list
4496   int j = 0;
4497   for (int i = 0; i < _expensive_nodes->length(); i++) {
4498     Node* n = _expensive_nodes->at(i);
4499     if (!n->is_unreachable(igvn)) {
4500       assert(n->is_expensive(), "should be expensive");
4501       _expensive_nodes->at_put(j, n);
4502       j++;
4503     }
4504   }
4505   _expensive_nodes->trunc_to(j);
4506 
4507   // Then sort the list so that similar nodes are next to each other
4508   // and check for at least two nodes of identical kind with same data
4509   // inputs.
4510   sort_expensive_nodes();
4511 
4512   for (int i = 0; i < _expensive_nodes->length()-1; i++) {
4513     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
4514       return true;
4515     }
4516   }
4517 
4518   return false;
4519 }
4520 
4521 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
4522   if (_expensive_nodes->length() == 0) {
4523     return;
4524   }
4525 
4526   assert(OptimizeExpensiveOps, "optimization off?");
4527 
4528   // Sort to bring similar nodes next to each other and clear the
4529   // control input of nodes for which there's only a single copy.
4530   sort_expensive_nodes();
4531 
4532   int j = 0;
4533   int identical = 0;
4534   int i = 0;
4535   bool modified = false;
4536   for (; i < _expensive_nodes->length()-1; i++) {
4537     assert(j <= i, "can't write beyond current index");
4538     if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
4539       identical++;
4540       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4541       continue;
4542     }
4543     if (identical > 0) {
4544       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4545       identical = 0;
4546     } else {
4547       Node* n = _expensive_nodes->at(i);
4548       igvn.replace_input_of(n, 0, NULL);
4549       igvn.hash_insert(n);
4550       modified = true;
4551     }
4552   }
4553   if (identical > 0) {
4554     _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4555   } else if (_expensive_nodes->length() >= 1) {
4556     Node* n = _expensive_nodes->at(i);
4557     igvn.replace_input_of(n, 0, NULL);
4558     igvn.hash_insert(n);
4559     modified = true;
4560   }
4561   _expensive_nodes->trunc_to(j);
4562   if (modified) {
4563     igvn.optimize();
4564   }
4565 }
4566 
4567 void Compile::add_expensive_node(Node * n) {
4568   assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
4569   assert(n->is_expensive(), "expensive nodes with non-null control here only");
4570   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
4571   if (OptimizeExpensiveOps) {
4572     _expensive_nodes->append(n);
4573   } else {
4574     // Clear control input and let IGVN optimize expensive nodes if
4575     // OptimizeExpensiveOps is off.
4576     n->set_req(0, NULL);
4577   }
4578 }
4579 
4580 /**
4581  * Remove the speculative part of types and clean up the graph
4582  */
4583 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
4584   if (UseTypeSpeculation) {
4585     Unique_Node_List worklist;
4586     worklist.push(root());
4587     int modified = 0;
4588     // Go over all type nodes that carry a speculative type, drop the
4589     // speculative part of the type and enqueue the node for an igvn
4590     // which may optimize it out.
4591     for (uint next = 0; next < worklist.size(); ++next) {
4592       Node *n  = worklist.at(next);
4593       if (n->is_Type()) {
4594         TypeNode* tn = n->as_Type();
4595         const Type* t = tn->type();
4596         const Type* t_no_spec = t->remove_speculative();
4597         if (t_no_spec != t) {
4598           bool in_hash = igvn.hash_delete(n);
4599           assert(in_hash, "node should be in igvn hash table");
4600           tn->set_type(t_no_spec);
4601           igvn.hash_insert(n);
4602           igvn._worklist.push(n); // give it a chance to go away
4603           modified++;
4604         }
4605       }
4606       uint max = n->len();
4607       for( uint i = 0; i < max; ++i ) {
4608         Node *m = n->in(i);
4609         if (not_a_node(m))  continue;
4610         worklist.push(m);
4611       }
4612     }
4613     // Drop the speculative part of all types in the igvn's type table
4614     igvn.remove_speculative_types();
4615     if (modified > 0) {
4616       igvn.optimize();
4617     }
4618 #ifdef ASSERT
4619     // Verify that after the IGVN is over no speculative type has resurfaced
4620     worklist.clear();
4621     worklist.push(root());
4622     for (uint next = 0; next < worklist.size(); ++next) {
4623       Node *n  = worklist.at(next);
4624       const Type* t = igvn.type_or_null(n);
4625       assert((t == NULL) || (t == t->remove_speculative()), "no more speculative types");
4626       if (n->is_Type()) {
4627         t = n->as_Type()->type();
4628         assert(t == t->remove_speculative(), "no more speculative types");
4629       }
4630       uint max = n->len();
4631       for( uint i = 0; i < max; ++i ) {
4632         Node *m = n->in(i);
4633         if (not_a_node(m))  continue;
4634         worklist.push(m);
4635       }
4636     }
4637     igvn.check_no_speculative_types();
4638 #endif
4639   }
4640 }
4641 
4642 Node* Compile::optimize_acmp(PhaseGVN* phase, Node* a, Node* b) {
4643   const TypeInstPtr* ta = phase->type(a)->isa_instptr();
4644   const TypeInstPtr* tb = phase->type(b)->isa_instptr();
4645   if (!EnableValhalla || ta == NULL || tb == NULL ||
4646       ta->is_zero_type() || tb->is_zero_type() ||
4647       !ta->can_be_value_type() || !tb->can_be_value_type()) {
4648     // Use old acmp if one operand is null or not a value type
4649     return new CmpPNode(a, b);
4650   } else if (ta->is_valuetypeptr() || tb->is_valuetypeptr()) {
4651     // We know that one operand is a value type. Therefore,
4652     // new acmp will only return true if both operands are NULL.
4653     // Check if both operands are null by or'ing the oops.
4654     a = phase->transform(new CastP2XNode(NULL, a));
4655     b = phase->transform(new CastP2XNode(NULL, b));
4656     a = phase->transform(new OrXNode(a, b));
4657     return new CmpXNode(a, phase->MakeConX(0));
4658   }
4659   // Use new acmp
4660   return NULL;
4661 }
4662 
4663 // Auxiliary method to support randomized stressing/fuzzing.
4664 //
4665 // This method can be called the arbitrary number of times, with current count
4666 // as the argument. The logic allows selecting a single candidate from the
4667 // running list of candidates as follows:
4668 //    int count = 0;
4669 //    Cand* selected = null;
4670 //    while(cand = cand->next()) {
4671 //      if (randomized_select(++count)) {
4672 //        selected = cand;
4673 //      }
4674 //    }
4675 //
4676 // Including count equalizes the chances any candidate is "selected".
4677 // This is useful when we don't have the complete list of candidates to choose
4678 // from uniformly. In this case, we need to adjust the randomicity of the
4679 // selection, or else we will end up biasing the selection towards the latter
4680 // candidates.
4681 //
4682 // Quick back-envelope calculation shows that for the list of n candidates
4683 // the equal probability for the candidate to persist as "best" can be
4684 // achieved by replacing it with "next" k-th candidate with the probability
4685 // of 1/k. It can be easily shown that by the end of the run, the
4686 // probability for any candidate is converged to 1/n, thus giving the
4687 // uniform distribution among all the candidates.
4688 //
4689 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
4690 #define RANDOMIZED_DOMAIN_POW 29
4691 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
4692 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
4693 bool Compile::randomized_select(int count) {
4694   assert(count > 0, "only positive");
4695   return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);
4696 }
4697 
4698 CloneMap&     Compile::clone_map()                 { return _clone_map; }
4699 void          Compile::set_clone_map(Dict* d)      { _clone_map._dict = d; }
4700 
4701 void NodeCloneInfo::dump() const {
4702   tty->print(" {%d:%d} ", idx(), gen());
4703 }
4704 
4705 void CloneMap::clone(Node* old, Node* nnn, int gen) {
4706   uint64_t val = value(old->_idx);
4707   NodeCloneInfo cio(val);
4708   assert(val != 0, "old node should be in the map");
4709   NodeCloneInfo cin(cio.idx(), gen + cio.gen());
4710   insert(nnn->_idx, cin.get());
4711 #ifndef PRODUCT
4712   if (is_debug()) {
4713     tty->print_cr("CloneMap::clone inserted node %d info {%d:%d} into CloneMap", nnn->_idx, cin.idx(), cin.gen());
4714   }
4715 #endif
4716 }
4717 
4718 void CloneMap::verify_insert_and_clone(Node* old, Node* nnn, int gen) {
4719   NodeCloneInfo cio(value(old->_idx));
4720   if (cio.get() == 0) {
4721     cio.set(old->_idx, 0);
4722     insert(old->_idx, cio.get());
4723 #ifndef PRODUCT
4724     if (is_debug()) {
4725       tty->print_cr("CloneMap::verify_insert_and_clone inserted node %d info {%d:%d} into CloneMap", old->_idx, cio.idx(), cio.gen());
4726     }
4727 #endif
4728   }
4729   clone(old, nnn, gen);
4730 }
4731 
4732 int CloneMap::max_gen() const {
4733   int g = 0;
4734   DictI di(_dict);
4735   for(; di.test(); ++di) {
4736     int t = gen(di._key);
4737     if (g < t) {
4738       g = t;
4739 #ifndef PRODUCT
4740       if (is_debug()) {
4741         tty->print_cr("CloneMap::max_gen() update max=%d from %d", g, _2_node_idx_t(di._key));
4742       }
4743 #endif
4744     }
4745   }
4746   return g;
4747 }
4748 
4749 void CloneMap::dump(node_idx_t key) const {
4750   uint64_t val = value(key);
4751   if (val != 0) {
4752     NodeCloneInfo ni(val);
4753     ni.dump();
4754   }
4755 }