1 /*
   2  * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "asm/macroAssembler.hpp"
  27 #include "asm/macroAssembler.inline.hpp"
  28 #include "ci/ciReplay.hpp"
  29 #include "classfile/systemDictionary.hpp"
  30 #include "code/exceptionHandlerTable.hpp"
  31 #include "code/nmethod.hpp"
  32 #include "compiler/compileBroker.hpp"
  33 #include "compiler/compileLog.hpp"
  34 #include "compiler/disassembler.hpp"
  35 #include "compiler/oopMap.hpp"
  36 #include "gc/shared/barrierSet.hpp"
  37 #include "gc/shared/c2/barrierSetC2.hpp"
  38 #include "memory/resourceArea.hpp"
  39 #include "opto/addnode.hpp"
  40 #include "opto/block.hpp"
  41 #include "opto/c2compiler.hpp"
  42 #include "opto/callGenerator.hpp"
  43 #include "opto/callnode.hpp"
  44 #include "opto/castnode.hpp"
  45 #include "opto/cfgnode.hpp"
  46 #include "opto/chaitin.hpp"
  47 #include "opto/compile.hpp"
  48 #include "opto/connode.hpp"
  49 #include "opto/convertnode.hpp"
  50 #include "opto/divnode.hpp"
  51 #include "opto/escape.hpp"
  52 #include "opto/idealGraphPrinter.hpp"
  53 #include "opto/loopnode.hpp"
  54 #include "opto/machnode.hpp"
  55 #include "opto/macro.hpp"
  56 #include "opto/matcher.hpp"
  57 #include "opto/mathexactnode.hpp"
  58 #include "opto/memnode.hpp"
  59 #include "opto/mulnode.hpp"
  60 #include "opto/narrowptrnode.hpp"
  61 #include "opto/node.hpp"
  62 #include "opto/opcodes.hpp"
  63 #include "opto/output.hpp"
  64 #include "opto/parse.hpp"
  65 #include "opto/phaseX.hpp"
  66 #include "opto/rootnode.hpp"
  67 #include "opto/runtime.hpp"
  68 #include "opto/stringopts.hpp"
  69 #include "opto/type.hpp"
  70 #include "opto/vectornode.hpp"
  71 #include "runtime/arguments.hpp"
  72 #include "runtime/sharedRuntime.hpp"
  73 #include "runtime/signature.hpp"
  74 #include "runtime/stubRoutines.hpp"
  75 #include "runtime/timer.hpp"
  76 #include "utilities/align.hpp"
  77 #include "utilities/copy.hpp"
  78 #include "utilities/macros.hpp"
  79 #if INCLUDE_G1GC
  80 #include "gc/g1/g1ThreadLocalData.hpp"
  81 #endif // INCLUDE_G1GC
  82 #if INCLUDE_ZGC
  83 #include "gc/z/c2/zBarrierSetC2.hpp"
  84 #endif
  85 
  86 
  87 // -------------------- Compile::mach_constant_base_node -----------------------
  88 // Constant table base node singleton.
  89 MachConstantBaseNode* Compile::mach_constant_base_node() {
  90   if (_mach_constant_base_node == NULL) {
  91     _mach_constant_base_node = new MachConstantBaseNode();
  92     _mach_constant_base_node->add_req(C->root());
  93   }
  94   return _mach_constant_base_node;
  95 }
  96 
  97 
  98 /// Support for intrinsics.
  99 
 100 // Return the index at which m must be inserted (or already exists).
 101 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
 102 class IntrinsicDescPair {
 103  private:
 104   ciMethod* _m;
 105   bool _is_virtual;
 106  public:
 107   IntrinsicDescPair(ciMethod* m, bool is_virtual) : _m(m), _is_virtual(is_virtual) {}
 108   static int compare(IntrinsicDescPair* const& key, CallGenerator* const& elt) {
 109     ciMethod* m= elt->method();
 110     ciMethod* key_m = key->_m;
 111     if (key_m < m)      return -1;
 112     else if (key_m > m) return 1;
 113     else {
 114       bool is_virtual = elt->is_virtual();
 115       bool key_virtual = key->_is_virtual;
 116       if (key_virtual < is_virtual)      return -1;
 117       else if (key_virtual > is_virtual) return 1;
 118       else                               return 0;
 119     }
 120   }
 121 };
 122 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual, bool& found) {
 123 #ifdef ASSERT
 124   for (int i = 1; i < _intrinsics->length(); i++) {
 125     CallGenerator* cg1 = _intrinsics->at(i-1);
 126     CallGenerator* cg2 = _intrinsics->at(i);
 127     assert(cg1->method() != cg2->method()
 128            ? cg1->method()     < cg2->method()
 129            : cg1->is_virtual() < cg2->is_virtual(),
 130            "compiler intrinsics list must stay sorted");
 131   }
 132 #endif
 133   IntrinsicDescPair pair(m, is_virtual);
 134   return _intrinsics->find_sorted<IntrinsicDescPair*, IntrinsicDescPair::compare>(&pair, found);
 135 }
 136 
 137 void Compile::register_intrinsic(CallGenerator* cg) {
 138   if (_intrinsics == NULL) {
 139     _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
 140   }
 141   int len = _intrinsics->length();
 142   bool found = false;
 143   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual(), found);
 144   assert(!found, "registering twice");
 145   _intrinsics->insert_before(index, cg);
 146   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
 147 }
 148 
 149 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
 150   assert(m->is_loaded(), "don't try this on unloaded methods");
 151   if (_intrinsics != NULL) {
 152     bool found = false;
 153     int index = intrinsic_insertion_index(m, is_virtual, found);
 154      if (found) {
 155       return _intrinsics->at(index);
 156     }
 157   }
 158   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
 159   if (m->intrinsic_id() != vmIntrinsics::_none &&
 160       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
 161     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
 162     if (cg != NULL) {
 163       // Save it for next time:
 164       register_intrinsic(cg);
 165       return cg;
 166     } else {
 167       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
 168     }
 169   }
 170   return NULL;
 171 }
 172 
 173 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
 174 // in library_call.cpp.
 175 
 176 
 177 #ifndef PRODUCT
 178 // statistics gathering...
 179 
 180 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
 181 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
 182 
 183 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
 184   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
 185   int oflags = _intrinsic_hist_flags[id];
 186   assert(flags != 0, "what happened?");
 187   if (is_virtual) {
 188     flags |= _intrinsic_virtual;
 189   }
 190   bool changed = (flags != oflags);
 191   if ((flags & _intrinsic_worked) != 0) {
 192     juint count = (_intrinsic_hist_count[id] += 1);
 193     if (count == 1) {
 194       changed = true;           // first time
 195     }
 196     // increment the overall count also:
 197     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
 198   }
 199   if (changed) {
 200     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
 201       // Something changed about the intrinsic's virtuality.
 202       if ((flags & _intrinsic_virtual) != 0) {
 203         // This is the first use of this intrinsic as a virtual call.
 204         if (oflags != 0) {
 205           // We already saw it as a non-virtual, so note both cases.
 206           flags |= _intrinsic_both;
 207         }
 208       } else if ((oflags & _intrinsic_both) == 0) {
 209         // This is the first use of this intrinsic as a non-virtual
 210         flags |= _intrinsic_both;
 211       }
 212     }
 213     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
 214   }
 215   // update the overall flags also:
 216   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
 217   return changed;
 218 }
 219 
 220 static char* format_flags(int flags, char* buf) {
 221   buf[0] = 0;
 222   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
 223   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
 224   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
 225   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
 226   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
 227   if (buf[0] == 0)  strcat(buf, ",");
 228   assert(buf[0] == ',', "must be");
 229   return &buf[1];
 230 }
 231 
 232 void Compile::print_intrinsic_statistics() {
 233   char flagsbuf[100];
 234   ttyLocker ttyl;
 235   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
 236   tty->print_cr("Compiler intrinsic usage:");
 237   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
 238   if (total == 0)  total = 1;  // avoid div0 in case of no successes
 239   #define PRINT_STAT_LINE(name, c, f) \
 240     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
 241   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
 242     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
 243     int   flags = _intrinsic_hist_flags[id];
 244     juint count = _intrinsic_hist_count[id];
 245     if ((flags | count) != 0) {
 246       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
 247     }
 248   }
 249   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
 250   if (xtty != NULL)  xtty->tail("statistics");
 251 }
 252 
 253 void Compile::print_statistics() {
 254   { ttyLocker ttyl;
 255     if (xtty != NULL)  xtty->head("statistics type='opto'");
 256     Parse::print_statistics();
 257     PhaseCCP::print_statistics();
 258     PhaseRegAlloc::print_statistics();
 259     Scheduling::print_statistics();
 260     PhasePeephole::print_statistics();
 261     PhaseIdealLoop::print_statistics();
 262     if (xtty != NULL)  xtty->tail("statistics");
 263   }
 264   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
 265     // put this under its own <statistics> element.
 266     print_intrinsic_statistics();
 267   }
 268 }
 269 #endif //PRODUCT
 270 
 271 // Support for bundling info
 272 Bundle* Compile::node_bundling(const Node *n) {
 273   assert(valid_bundle_info(n), "oob");
 274   return &_node_bundling_base[n->_idx];
 275 }
 276 
 277 bool Compile::valid_bundle_info(const Node *n) {
 278   return (_node_bundling_limit > n->_idx);
 279 }
 280 
 281 
 282 void Compile::gvn_replace_by(Node* n, Node* nn) {
 283   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
 284     Node* use = n->last_out(i);
 285     bool is_in_table = initial_gvn()->hash_delete(use);
 286     uint uses_found = 0;
 287     for (uint j = 0; j < use->len(); j++) {
 288       if (use->in(j) == n) {
 289         if (j < use->req())
 290           use->set_req(j, nn);
 291         else
 292           use->set_prec(j, nn);
 293         uses_found++;
 294       }
 295     }
 296     if (is_in_table) {
 297       // reinsert into table
 298       initial_gvn()->hash_find_insert(use);
 299     }
 300     record_for_igvn(use);
 301     i -= uses_found;    // we deleted 1 or more copies of this edge
 302   }
 303 }
 304 
 305 
 306 static inline bool not_a_node(const Node* n) {
 307   if (n == NULL)                   return true;
 308   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
 309   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
 310   return false;
 311 }
 312 
 313 // Identify all nodes that are reachable from below, useful.
 314 // Use breadth-first pass that records state in a Unique_Node_List,
 315 // recursive traversal is slower.
 316 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
 317   int estimated_worklist_size = live_nodes();
 318   useful.map( estimated_worklist_size, NULL );  // preallocate space
 319 
 320   // Initialize worklist
 321   if (root() != NULL)     { useful.push(root()); }
 322   // If 'top' is cached, declare it useful to preserve cached node
 323   if( cached_top_node() ) { useful.push(cached_top_node()); }
 324 
 325   // Push all useful nodes onto the list, breadthfirst
 326   for( uint next = 0; next < useful.size(); ++next ) {
 327     assert( next < unique(), "Unique useful nodes < total nodes");
 328     Node *n  = useful.at(next);
 329     uint max = n->len();
 330     for( uint i = 0; i < max; ++i ) {
 331       Node *m = n->in(i);
 332       if (not_a_node(m))  continue;
 333       useful.push(m);
 334     }
 335   }
 336 }
 337 
 338 // Update dead_node_list with any missing dead nodes using useful
 339 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
 340 void Compile::update_dead_node_list(Unique_Node_List &useful) {
 341   uint max_idx = unique();
 342   VectorSet& useful_node_set = useful.member_set();
 343 
 344   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
 345     // If node with index node_idx is not in useful set,
 346     // mark it as dead in dead node list.
 347     if (! useful_node_set.test(node_idx) ) {
 348       record_dead_node(node_idx);
 349     }
 350   }
 351 }
 352 
 353 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
 354   int shift = 0;
 355   for (int i = 0; i < inlines->length(); i++) {
 356     CallGenerator* cg = inlines->at(i);
 357     CallNode* call = cg->call_node();
 358     if (shift > 0) {
 359       inlines->at_put(i-shift, cg);
 360     }
 361     if (!useful.member(call)) {
 362       shift++;
 363     }
 364   }
 365   inlines->trunc_to(inlines->length()-shift);
 366 }
 367 
 368 // Disconnect all useless nodes by disconnecting those at the boundary.
 369 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
 370   uint next = 0;
 371   while (next < useful.size()) {
 372     Node *n = useful.at(next++);
 373     if (n->is_SafePoint()) {
 374       // We're done with a parsing phase. Replaced nodes are not valid
 375       // beyond that point.
 376       n->as_SafePoint()->delete_replaced_nodes();
 377     }
 378     // Use raw traversal of out edges since this code removes out edges
 379     int max = n->outcnt();
 380     for (int j = 0; j < max; ++j) {
 381       Node* child = n->raw_out(j);
 382       if (! useful.member(child)) {
 383         assert(!child->is_top() || child != top(),
 384                "If top is cached in Compile object it is in useful list");
 385         // Only need to remove this out-edge to the useless node
 386         n->raw_del_out(j);
 387         --j;
 388         --max;
 389       }
 390     }
 391     if (n->outcnt() == 1 && n->has_special_unique_user()) {
 392       record_for_igvn(n->unique_out());
 393     }
 394   }
 395   // Remove useless macro and predicate opaq nodes
 396   for (int i = C->macro_count()-1; i >= 0; i--) {
 397     Node* n = C->macro_node(i);
 398     if (!useful.member(n)) {
 399       remove_macro_node(n);
 400     }
 401   }
 402   // Remove useless CastII nodes with range check dependency
 403   for (int i = range_check_cast_count() - 1; i >= 0; i--) {
 404     Node* cast = range_check_cast_node(i);
 405     if (!useful.member(cast)) {
 406       remove_range_check_cast(cast);
 407     }
 408   }
 409   // Remove useless expensive nodes
 410   for (int i = C->expensive_count()-1; i >= 0; i--) {
 411     Node* n = C->expensive_node(i);
 412     if (!useful.member(n)) {
 413       remove_expensive_node(n);
 414     }
 415   }
 416   // Remove useless Opaque4 nodes
 417   for (int i = opaque4_count() - 1; i >= 0; i--) {
 418     Node* opaq = opaque4_node(i);
 419     if (!useful.member(opaq)) {
 420       remove_opaque4_node(opaq);
 421     }
 422   }
 423   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 424   bs->eliminate_useless_gc_barriers(useful);
 425   // clean up the late inline lists
 426   remove_useless_late_inlines(&_string_late_inlines, useful);
 427   remove_useless_late_inlines(&_boxing_late_inlines, useful);
 428   remove_useless_late_inlines(&_late_inlines, useful);
 429   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
 430 }
 431 
 432 //------------------------------frame_size_in_words-----------------------------
 433 // frame_slots in units of words
 434 int Compile::frame_size_in_words() const {
 435   // shift is 0 in LP32 and 1 in LP64
 436   const int shift = (LogBytesPerWord - LogBytesPerInt);
 437   int words = _frame_slots >> shift;
 438   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
 439   return words;
 440 }
 441 
 442 // To bang the stack of this compiled method we use the stack size
 443 // that the interpreter would need in case of a deoptimization. This
 444 // removes the need to bang the stack in the deoptimization blob which
 445 // in turn simplifies stack overflow handling.
 446 int Compile::bang_size_in_bytes() const {
 447   return MAX2(frame_size_in_bytes() + os::extra_bang_size_in_bytes(), _interpreter_frame_size);
 448 }
 449 
 450 // ============================================================================
 451 //------------------------------CompileWrapper---------------------------------
 452 class CompileWrapper : public StackObj {
 453   Compile *const _compile;
 454  public:
 455   CompileWrapper(Compile* compile);
 456 
 457   ~CompileWrapper();
 458 };
 459 
 460 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
 461   // the Compile* pointer is stored in the current ciEnv:
 462   ciEnv* env = compile->env();
 463   assert(env == ciEnv::current(), "must already be a ciEnv active");
 464   assert(env->compiler_data() == NULL, "compile already active?");
 465   env->set_compiler_data(compile);
 466   assert(compile == Compile::current(), "sanity");
 467 
 468   compile->set_type_dict(NULL);
 469   compile->set_clone_map(new Dict(cmpkey, hashkey, _compile->comp_arena()));
 470   compile->clone_map().set_clone_idx(0);
 471   compile->set_type_hwm(NULL);
 472   compile->set_type_last_size(0);
 473   compile->set_last_tf(NULL, NULL);
 474   compile->set_indexSet_arena(NULL);
 475   compile->set_indexSet_free_block_list(NULL);
 476   compile->init_type_arena();
 477   Type::Initialize(compile);
 478   _compile->set_scratch_buffer_blob(NULL);
 479   _compile->begin_method();
 480   _compile->clone_map().set_debug(_compile->has_method() && _compile->directive()->CloneMapDebugOption);
 481 }
 482 CompileWrapper::~CompileWrapper() {
 483   _compile->end_method();
 484   if (_compile->scratch_buffer_blob() != NULL)
 485     BufferBlob::free(_compile->scratch_buffer_blob());
 486   _compile->env()->set_compiler_data(NULL);
 487 }
 488 
 489 
 490 //----------------------------print_compile_messages---------------------------
 491 void Compile::print_compile_messages() {
 492 #ifndef PRODUCT
 493   // Check if recompiling
 494   if (_subsume_loads == false && PrintOpto) {
 495     // Recompiling without allowing machine instructions to subsume loads
 496     tty->print_cr("*********************************************************");
 497     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
 498     tty->print_cr("*********************************************************");
 499   }
 500   if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
 501     // Recompiling without escape analysis
 502     tty->print_cr("*********************************************************");
 503     tty->print_cr("** Bailout: Recompile without escape analysis          **");
 504     tty->print_cr("*********************************************************");
 505   }
 506   if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
 507     // Recompiling without boxing elimination
 508     tty->print_cr("*********************************************************");
 509     tty->print_cr("** Bailout: Recompile without boxing elimination       **");
 510     tty->print_cr("*********************************************************");
 511   }
 512   if (C->directive()->BreakAtCompileOption) {
 513     // Open the debugger when compiling this method.
 514     tty->print("### Breaking when compiling: ");
 515     method()->print_short_name();
 516     tty->cr();
 517     BREAKPOINT;
 518   }
 519 
 520   if( PrintOpto ) {
 521     if (is_osr_compilation()) {
 522       tty->print("[OSR]%3d", _compile_id);
 523     } else {
 524       tty->print("%3d", _compile_id);
 525     }
 526   }
 527 #endif
 528 }
 529 
 530 
 531 //-----------------------init_scratch_buffer_blob------------------------------
 532 // Construct a temporary BufferBlob and cache it for this compile.
 533 void Compile::init_scratch_buffer_blob(int const_size) {
 534   // If there is already a scratch buffer blob allocated and the
 535   // constant section is big enough, use it.  Otherwise free the
 536   // current and allocate a new one.
 537   BufferBlob* blob = scratch_buffer_blob();
 538   if ((blob != NULL) && (const_size <= _scratch_const_size)) {
 539     // Use the current blob.
 540   } else {
 541     if (blob != NULL) {
 542       BufferBlob::free(blob);
 543     }
 544 
 545     ResourceMark rm;
 546     _scratch_const_size = const_size;
 547     int locs_size = sizeof(relocInfo) * MAX_locs_size;
 548     int slop = 2 * CodeSection::end_slop(); // space between sections
 549     int size = (MAX_inst_size + MAX_stubs_size + _scratch_const_size + slop + locs_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   if (is_branch) // Restore label.
 621     n->as_MachBranch()->label_set(saveL, save_bnum);
 622 
 623   // End scratch_emit_size section.
 624   set_in_scratch_emit_size(false);
 625 
 626   return buf.insts_size();
 627 }
 628 
 629 
 630 // ============================================================================
 631 //------------------------------Compile standard-------------------------------
 632 debug_only( int Compile::_debug_idx = 100000; )
 633 
 634 // Compile a method.  entry_bci is -1 for normal compilations and indicates
 635 // the continuation bci for on stack replacement.
 636 
 637 
 638 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
 639                   bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing, DirectiveSet* directive)
 640                 : Phase(Compiler),
 641                   _compile_id(ci_env->compile_id()),
 642                   _save_argument_registers(false),
 643                   _subsume_loads(subsume_loads),
 644                   _do_escape_analysis(do_escape_analysis),
 645                   _eliminate_boxing(eliminate_boxing),
 646                   _method(target),
 647                   _entry_bci(osr_bci),
 648                   _stub_function(NULL),
 649                   _stub_name(NULL),
 650                   _stub_entry_point(NULL),
 651                   _max_node_limit(MaxNodeLimit),
 652                   _orig_pc_slot(0),
 653                   _orig_pc_slot_offset_in_bytes(0),
 654                   _inlining_progress(false),
 655                   _inlining_incrementally(false),
 656                   _has_reserved_stack_access(target->has_reserved_stack_access()),
 657 #ifndef PRODUCT
 658                   _trace_opto_output(directive->TraceOptoOutputOption),
 659 #endif
 660                   _has_method_handle_invokes(false),
 661                   _comp_arena(mtCompiler),
 662                   _barrier_set_state(BarrierSet::barrier_set()->barrier_set_c2()->create_barrier_state(comp_arena())),
 663                   _env(ci_env),
 664                   _directive(directive),
 665                   _log(ci_env->log()),
 666                   _failure_reason(NULL),
 667                   _congraph(NULL),
 668 #ifndef PRODUCT
 669                   _printer(IdealGraphPrinter::printer()),
 670 #endif
 671                   _dead_node_list(comp_arena()),
 672                   _dead_node_count(0),
 673                   _node_arena(mtCompiler),
 674                   _old_arena(mtCompiler),
 675                   _mach_constant_base_node(NULL),
 676                   _Compile_types(mtCompiler),
 677                   _initial_gvn(NULL),
 678                   _for_igvn(NULL),
 679                   _warm_calls(NULL),
 680                   _late_inlines(comp_arena(), 2, 0, NULL),
 681                   _string_late_inlines(comp_arena(), 2, 0, NULL),
 682                   _boxing_late_inlines(comp_arena(), 2, 0, NULL),
 683                   _late_inlines_pos(0),
 684                   _number_of_mh_late_inlines(0),
 685                   _print_inlining_stream(NULL),
 686                   _print_inlining_list(NULL),
 687                   _print_inlining_idx(0),
 688                   _print_inlining_output(NULL),
 689                   _replay_inline_data(NULL),
 690                   _java_calls(0),
 691                   _inner_loops(0),
 692                   _interpreter_frame_size(0),
 693                   _node_bundling_limit(0),
 694                   _node_bundling_base(NULL),
 695                   _code_buffer("Compile::Fill_buffer"),
 696                   _scratch_const_size(-1),
 697                   _in_scratch_emit_size(false)
 698 #ifndef PRODUCT
 699                   , _in_dump_cnt(0)
 700 #endif
 701 {
 702   C = this;
 703 #ifndef PRODUCT
 704   if (_printer != NULL) {
 705     _printer->set_compile(this);
 706   }
 707 #endif
 708   CompileWrapper cw(this);
 709 
 710   if (CITimeVerbose) {
 711     tty->print(" ");
 712     target->holder()->name()->print();
 713     tty->print(".");
 714     target->print_short_name();
 715     tty->print("  ");
 716   }
 717   TraceTime t1("Total compilation time", &_t_totalCompilation, CITime, CITimeVerbose);
 718   TraceTime t2(NULL, &_t_methodCompilation, CITime, false);
 719 
 720 #ifndef PRODUCT
 721   bool print_opto_assembly = directive->PrintOptoAssemblyOption;
 722   if (!print_opto_assembly) {
 723     bool print_assembly = directive->PrintAssemblyOption;
 724     if (print_assembly && !Disassembler::can_decode()) {
 725       tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
 726       print_opto_assembly = true;
 727     }
 728   }
 729   set_print_assembly(print_opto_assembly);
 730   set_parsed_irreducible_loop(false);
 731 
 732   if (directive->ReplayInlineOption) {
 733     _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
 734   }
 735 #endif
 736   set_print_inlining(directive->PrintInliningOption || PrintOptoInlining);
 737   set_print_intrinsics(directive->PrintIntrinsicsOption);
 738   set_has_irreducible_loop(true); // conservative until build_loop_tree() reset it
 739 
 740   if (ProfileTraps RTM_OPT_ONLY( || UseRTMLocking )) {
 741     // Make sure the method being compiled gets its own MDO,
 742     // so we can at least track the decompile_count().
 743     // Need MDO to record RTM code generation state.
 744     method()->ensure_method_data();
 745   }
 746 
 747   Init(::AliasLevel);
 748 
 749 
 750   print_compile_messages();
 751 
 752   _ilt = InlineTree::build_inline_tree_root();
 753 
 754   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
 755   assert(num_alias_types() >= AliasIdxRaw, "");
 756 
 757 #define MINIMUM_NODE_HASH  1023
 758   // Node list that Iterative GVN will start with
 759   Unique_Node_List for_igvn(comp_arena());
 760   set_for_igvn(&for_igvn);
 761 
 762   // GVN that will be run immediately on new nodes
 763   uint estimated_size = method()->code_size()*4+64;
 764   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
 765   PhaseGVN gvn(node_arena(), estimated_size);
 766   set_initial_gvn(&gvn);
 767 
 768   print_inlining_init();
 769   { // Scope for timing the parser
 770     TracePhase tp("parse", &timers[_t_parser]);
 771 
 772     // Put top into the hash table ASAP.
 773     initial_gvn()->transform_no_reclaim(top());
 774 
 775     // Set up tf(), start(), and find a CallGenerator.
 776     CallGenerator* cg = NULL;
 777     if (is_osr_compilation()) {
 778       const TypeTuple *domain = StartOSRNode::osr_domain();
 779       const TypeTuple *range = TypeTuple::make_range(method()->signature());
 780       init_tf(TypeFunc::make(domain, range));
 781       StartNode* s = new StartOSRNode(root(), domain);
 782       initial_gvn()->set_type_bottom(s);
 783       init_start(s);
 784       cg = CallGenerator::for_osr(method(), entry_bci());
 785     } else {
 786       // Normal case.
 787       init_tf(TypeFunc::make(method()));
 788       StartNode* s = new StartNode(root(), tf()->domain());
 789       initial_gvn()->set_type_bottom(s);
 790       init_start(s);
 791       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get) {
 792         // With java.lang.ref.reference.get() we must go through the
 793         // intrinsic - even when get() is the root
 794         // method of the compile - so that, if necessary, the value in
 795         // the referent field of the reference object gets recorded by
 796         // the pre-barrier code.
 797         cg = find_intrinsic(method(), false);
 798       }
 799       if (cg == NULL) {
 800         float past_uses = method()->interpreter_invocation_count();
 801         float expected_uses = past_uses;
 802         cg = CallGenerator::for_inline(method(), expected_uses);
 803       }
 804     }
 805     if (failing())  return;
 806     if (cg == NULL) {
 807       record_method_not_compilable("cannot parse method");
 808       return;
 809     }
 810     JVMState* jvms = build_start_state(start(), tf());
 811     if ((jvms = cg->generate(jvms)) == NULL) {
 812       if (!failure_reason_is(C2Compiler::retry_class_loading_during_parsing())) {
 813         record_method_not_compilable("method parse failed");
 814       }
 815       return;
 816     }
 817     GraphKit kit(jvms);
 818 
 819     if (!kit.stopped()) {
 820       // Accept return values, and transfer control we know not where.
 821       // This is done by a special, unique ReturnNode bound to root.
 822       return_values(kit.jvms());
 823     }
 824 
 825     if (kit.has_exceptions()) {
 826       // Any exceptions that escape from this call must be rethrown
 827       // to whatever caller is dynamically above us on the stack.
 828       // This is done by a special, unique RethrowNode bound to root.
 829       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
 830     }
 831 
 832     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
 833 
 834     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
 835       inline_string_calls(true);
 836     }
 837 
 838     if (failing())  return;
 839 
 840     print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
 841 
 842     // Remove clutter produced by parsing.
 843     if (!failing()) {
 844       ResourceMark rm;
 845       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
 846     }
 847   }
 848 
 849   // Note:  Large methods are capped off in do_one_bytecode().
 850   if (failing())  return;
 851 
 852   // After parsing, node notes are no longer automagic.
 853   // They must be propagated by register_new_node_with_optimizer(),
 854   // clone(), or the like.
 855   set_default_node_notes(NULL);
 856 
 857   for (;;) {
 858     int successes = Inline_Warm();
 859     if (failing())  return;
 860     if (successes == 0)  break;
 861   }
 862 
 863   // Drain the list.
 864   Finish_Warm();
 865 #ifndef PRODUCT
 866   if (_printer && _printer->should_print(1)) {
 867     _printer->print_inlining();
 868   }
 869 #endif
 870 
 871   if (failing())  return;
 872   NOT_PRODUCT( verify_graph_edges(); )
 873 
 874   // Now optimize
 875   Optimize();
 876   if (failing())  return;
 877   NOT_PRODUCT( verify_graph_edges(); )
 878 
 879 #ifndef PRODUCT
 880   if (PrintIdeal) {
 881     ttyLocker ttyl;  // keep the following output all in one block
 882     // This output goes directly to the tty, not the compiler log.
 883     // To enable tools to match it up with the compilation activity,
 884     // be sure to tag this tty output with the compile ID.
 885     if (xtty != NULL) {
 886       xtty->head("ideal compile_id='%d'%s", compile_id(),
 887                  is_osr_compilation()    ? " compile_kind='osr'" :
 888                  "");
 889     }
 890     root()->dump(9999);
 891     if (xtty != NULL) {
 892       xtty->tail("ideal");
 893     }
 894   }
 895 #endif
 896 
 897   NOT_PRODUCT( verify_barriers(); )
 898 
 899   // Dump compilation data to replay it.
 900   if (directive->DumpReplayOption) {
 901     env()->dump_replay_data(_compile_id);
 902   }
 903   if (directive->DumpInlineOption && (ilt() != NULL)) {
 904     env()->dump_inline_data(_compile_id);
 905   }
 906 
 907   // Now that we know the size of all the monitors we can add a fixed slot
 908   // for the original deopt pc.
 909 
 910   _orig_pc_slot =  fixed_slots();
 911   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
 912   set_fixed_slots(next_slot);
 913 
 914   // Compute when to use implicit null checks. Used by matching trap based
 915   // nodes and NullCheck optimization.
 916   set_allowed_deopt_reasons();
 917 
 918   // Now generate code
 919   Code_Gen();
 920   if (failing())  return;
 921 
 922   // Check if we want to skip execution of all compiled code.
 923   {
 924 #ifndef PRODUCT
 925     if (OptoNoExecute) {
 926       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
 927       return;
 928     }
 929 #endif
 930     TracePhase tp("install_code", &timers[_t_registerMethod]);
 931 
 932     if (is_osr_compilation()) {
 933       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
 934       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
 935     } else {
 936       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
 937       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
 938     }
 939 
 940     env()->register_method(_method, _entry_bci,
 941                            &_code_offsets,
 942                            _orig_pc_slot_offset_in_bytes,
 943                            code_buffer(),
 944                            frame_size_in_words(), _oop_map_set,
 945                            &_handler_table, &_inc_table,
 946                            compiler,
 947                            has_unsafe_access(),
 948                            SharedRuntime::is_wide_vector(max_vector_size()),
 949                            rtm_state()
 950                            );
 951 
 952     if (log() != NULL) // Print code cache state into compiler log
 953       log()->code_cache_state();
 954   }
 955 }
 956 
 957 //------------------------------Compile----------------------------------------
 958 // Compile a runtime stub
 959 Compile::Compile( ciEnv* ci_env,
 960                   TypeFunc_generator generator,
 961                   address stub_function,
 962                   const char *stub_name,
 963                   int is_fancy_jump,
 964                   bool pass_tls,
 965                   bool save_arg_registers,
 966                   bool return_pc,
 967                   DirectiveSet* directive)
 968   : Phase(Compiler),
 969     _compile_id(0),
 970     _save_argument_registers(save_arg_registers),
 971     _subsume_loads(true),
 972     _do_escape_analysis(false),
 973     _eliminate_boxing(false),
 974     _method(NULL),
 975     _entry_bci(InvocationEntryBci),
 976     _stub_function(stub_function),
 977     _stub_name(stub_name),
 978     _stub_entry_point(NULL),
 979     _max_node_limit(MaxNodeLimit),
 980     _orig_pc_slot(0),
 981     _orig_pc_slot_offset_in_bytes(0),
 982     _inlining_progress(false),
 983     _inlining_incrementally(false),
 984     _has_reserved_stack_access(false),
 985 #ifndef PRODUCT
 986     _trace_opto_output(directive->TraceOptoOutputOption),
 987 #endif
 988     _has_method_handle_invokes(false),
 989     _comp_arena(mtCompiler),
 990     _env(ci_env),
 991     _directive(directive),
 992     _log(ci_env->log()),
 993     _failure_reason(NULL),
 994     _congraph(NULL),
 995 #ifndef PRODUCT
 996     _printer(NULL),
 997 #endif
 998     _dead_node_list(comp_arena()),
 999     _dead_node_count(0),
1000     _node_arena(mtCompiler),
1001     _old_arena(mtCompiler),
1002     _mach_constant_base_node(NULL),
1003     _Compile_types(mtCompiler),
1004     _initial_gvn(NULL),
1005     _for_igvn(NULL),
1006     _warm_calls(NULL),
1007     _number_of_mh_late_inlines(0),
1008     _print_inlining_stream(NULL),
1009     _print_inlining_list(NULL),
1010     _print_inlining_idx(0),
1011     _print_inlining_output(NULL),
1012     _replay_inline_data(NULL),
1013     _java_calls(0),
1014     _inner_loops(0),
1015     _interpreter_frame_size(0),
1016     _node_bundling_limit(0),
1017     _node_bundling_base(NULL),
1018     _code_buffer("Compile::Fill_buffer"),
1019 #ifndef PRODUCT
1020     _in_dump_cnt(0),
1021 #endif
1022     _allowed_reasons(0) {
1023   C = this;
1024 
1025   TraceTime t1(NULL, &_t_totalCompilation, CITime, false);
1026   TraceTime t2(NULL, &_t_stubCompilation, CITime, false);
1027 
1028 #ifndef PRODUCT
1029   set_print_assembly(PrintFrameConverterAssembly);
1030   set_parsed_irreducible_loop(false);
1031 #endif
1032   set_has_irreducible_loop(false); // no loops
1033 
1034   CompileWrapper cw(this);
1035   Init(/*AliasLevel=*/ 0);
1036   init_tf((*generator)());
1037 
1038   {
1039     // The following is a dummy for the sake of GraphKit::gen_stub
1040     Unique_Node_List for_igvn(comp_arena());
1041     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
1042     PhaseGVN gvn(Thread::current()->resource_area(),255);
1043     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
1044     gvn.transform_no_reclaim(top());
1045 
1046     GraphKit kit;
1047     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
1048   }
1049 
1050   NOT_PRODUCT( verify_graph_edges(); )
1051   Code_Gen();
1052   if (failing())  return;
1053 
1054 
1055   // Entry point will be accessed using compile->stub_entry_point();
1056   if (code_buffer() == NULL) {
1057     Matcher::soft_match_failure();
1058   } else {
1059     if (PrintAssembly && (WizardMode || Verbose))
1060       tty->print_cr("### Stub::%s", stub_name);
1061 
1062     if (!failing()) {
1063       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
1064 
1065       // Make the NMethod
1066       // For now we mark the frame as never safe for profile stackwalking
1067       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
1068                                                       code_buffer(),
1069                                                       CodeOffsets::frame_never_safe,
1070                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
1071                                                       frame_size_in_words(),
1072                                                       _oop_map_set,
1073                                                       save_arg_registers);
1074       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
1075 
1076       _stub_entry_point = rs->entry_point();
1077     }
1078   }
1079 }
1080 
1081 //------------------------------Init-------------------------------------------
1082 // Prepare for a single compilation
1083 void Compile::Init(int aliaslevel) {
1084   _unique  = 0;
1085   _regalloc = NULL;
1086 
1087   _tf      = NULL;  // filled in later
1088   _top     = NULL;  // cached later
1089   _matcher = NULL;  // filled in later
1090   _cfg     = NULL;  // filled in later
1091 
1092   set_24_bit_selection_and_mode(Use24BitFP, false);
1093 
1094   _node_note_array = NULL;
1095   _default_node_notes = NULL;
1096   DEBUG_ONLY( _modified_nodes = NULL; ) // Used in Optimize()
1097 
1098   _immutable_memory = NULL; // filled in at first inquiry
1099 
1100   // Globally visible Nodes
1101   // First set TOP to NULL to give safe behavior during creation of RootNode
1102   set_cached_top_node(NULL);
1103   set_root(new RootNode());
1104   // Now that you have a Root to point to, create the real TOP
1105   set_cached_top_node( new ConNode(Type::TOP) );
1106   set_recent_alloc(NULL, NULL);
1107 
1108   // Create Debug Information Recorder to record scopes, oopmaps, etc.
1109   env()->set_oop_recorder(new OopRecorder(env()->arena()));
1110   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
1111   env()->set_dependencies(new Dependencies(env()));
1112 
1113   _fixed_slots = 0;
1114   set_has_split_ifs(false);
1115   set_has_loops(has_method() && method()->has_loops()); // first approximation
1116   set_has_stringbuilder(false);
1117   set_has_boxed_value(false);
1118   _trap_can_recompile = false;  // no traps emitted yet
1119   _major_progress = true; // start out assuming good things will happen
1120   set_has_unsafe_access(false);
1121   set_max_vector_size(0);
1122   set_clear_upper_avx(false);  //false as default for clear upper bits of ymm registers
1123   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
1124   set_decompile_count(0);
1125 
1126   set_do_freq_based_layout(_directive->BlockLayoutByFrequencyOption);
1127   set_num_loop_opts(LoopOptsCount);
1128   set_do_inlining(Inline);
1129   set_max_inline_size(MaxInlineSize);
1130   set_freq_inline_size(FreqInlineSize);
1131   set_do_scheduling(OptoScheduling);
1132   set_do_count_invocations(false);
1133   set_do_method_data_update(false);
1134 
1135   set_do_vector_loop(false);
1136 
1137   if (AllowVectorizeOnDemand) {
1138     if (has_method() && (_directive->VectorizeOption || _directive->VectorizeDebugOption)) {
1139       set_do_vector_loop(true);
1140       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());})
1141     } else if (has_method() && method()->name() != 0 &&
1142                method()->intrinsic_id() == vmIntrinsics::_forEachRemaining) {
1143       set_do_vector_loop(true);
1144     }
1145   }
1146   set_use_cmove(UseCMoveUnconditionally /* || do_vector_loop()*/); //TODO: consider do_vector_loop() mandate use_cmove unconditionally
1147   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());})
1148 
1149   set_age_code(has_method() && method()->profile_aging());
1150   set_rtm_state(NoRTM); // No RTM lock eliding by default
1151   _max_node_limit = _directive->MaxNodeLimitOption;
1152 
1153 #if INCLUDE_RTM_OPT
1154   if (UseRTMLocking && has_method() && (method()->method_data_or_null() != NULL)) {
1155     int rtm_state = method()->method_data()->rtm_state();
1156     if (method_has_option("NoRTMLockEliding") || ((rtm_state & NoRTM) != 0)) {
1157       // Don't generate RTM lock eliding code.
1158       set_rtm_state(NoRTM);
1159     } else if (method_has_option("UseRTMLockEliding") || ((rtm_state & UseRTM) != 0) || !UseRTMDeopt) {
1160       // Generate RTM lock eliding code without abort ratio calculation code.
1161       set_rtm_state(UseRTM);
1162     } else if (UseRTMDeopt) {
1163       // Generate RTM lock eliding code and include abort ratio calculation
1164       // code if UseRTMDeopt is on.
1165       set_rtm_state(ProfileRTM);
1166     }
1167   }
1168 #endif
1169   if (debug_info()->recording_non_safepoints()) {
1170     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
1171                         (comp_arena(), 8, 0, NULL));
1172     set_default_node_notes(Node_Notes::make(this));
1173   }
1174 
1175   // // -- Initialize types before each compile --
1176   // // Update cached type information
1177   // if( _method && _method->constants() )
1178   //   Type::update_loaded_types(_method, _method->constants());
1179 
1180   // Init alias_type map.
1181   if (!_do_escape_analysis && aliaslevel == 3)
1182     aliaslevel = 2;  // No unique types without escape analysis
1183   _AliasLevel = aliaslevel;
1184   const int grow_ats = 16;
1185   _max_alias_types = grow_ats;
1186   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1187   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
1188   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1189   {
1190     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
1191   }
1192   // Initialize the first few types.
1193   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
1194   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1195   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1196   _num_alias_types = AliasIdxRaw+1;
1197   // Zero out the alias type cache.
1198   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1199   // A NULL adr_type hits in the cache right away.  Preload the right answer.
1200   probe_alias_cache(NULL)->_index = AliasIdxTop;
1201 
1202   _intrinsics = NULL;
1203   _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1204   _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1205   _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1206   _range_check_casts = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1207   _opaque4_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1208   register_library_intrinsics();
1209 }
1210 
1211 //---------------------------init_start----------------------------------------
1212 // Install the StartNode on this compile object.
1213 void Compile::init_start(StartNode* s) {
1214   if (failing())
1215     return; // already failing
1216   assert(s == start(), "");
1217 }
1218 
1219 /**
1220  * Return the 'StartNode'. We must not have a pending failure, since the ideal graph
1221  * can be in an inconsistent state, i.e., we can get segmentation faults when traversing
1222  * the ideal graph.
1223  */
1224 StartNode* Compile::start() const {
1225   assert (!failing(), "Must not have pending failure. Reason is: %s", failure_reason());
1226   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1227     Node* start = root()->fast_out(i);
1228     if (start->is_Start()) {
1229       return start->as_Start();
1230     }
1231   }
1232   fatal("Did not find Start node!");
1233   return NULL;
1234 }
1235 
1236 //-------------------------------immutable_memory-------------------------------------
1237 // Access immutable memory
1238 Node* Compile::immutable_memory() {
1239   if (_immutable_memory != NULL) {
1240     return _immutable_memory;
1241   }
1242   StartNode* s = start();
1243   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1244     Node *p = s->fast_out(i);
1245     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1246       _immutable_memory = p;
1247       return _immutable_memory;
1248     }
1249   }
1250   ShouldNotReachHere();
1251   return NULL;
1252 }
1253 
1254 //----------------------set_cached_top_node------------------------------------
1255 // Install the cached top node, and make sure Node::is_top works correctly.
1256 void Compile::set_cached_top_node(Node* tn) {
1257   if (tn != NULL)  verify_top(tn);
1258   Node* old_top = _top;
1259   _top = tn;
1260   // Calling Node::setup_is_top allows the nodes the chance to adjust
1261   // their _out arrays.
1262   if (_top != NULL)     _top->setup_is_top();
1263   if (old_top != NULL)  old_top->setup_is_top();
1264   assert(_top == NULL || top()->is_top(), "");
1265 }
1266 
1267 #ifdef ASSERT
1268 uint Compile::count_live_nodes_by_graph_walk() {
1269   Unique_Node_List useful(comp_arena());
1270   // Get useful node list by walking the graph.
1271   identify_useful_nodes(useful);
1272   return useful.size();
1273 }
1274 
1275 void Compile::print_missing_nodes() {
1276 
1277   // Return if CompileLog is NULL and PrintIdealNodeCount is false.
1278   if ((_log == NULL) && (! PrintIdealNodeCount)) {
1279     return;
1280   }
1281 
1282   // This is an expensive function. It is executed only when the user
1283   // specifies VerifyIdealNodeCount option or otherwise knows the
1284   // additional work that needs to be done to identify reachable nodes
1285   // by walking the flow graph and find the missing ones using
1286   // _dead_node_list.
1287 
1288   Unique_Node_List useful(comp_arena());
1289   // Get useful node list by walking the graph.
1290   identify_useful_nodes(useful);
1291 
1292   uint l_nodes = C->live_nodes();
1293   uint l_nodes_by_walk = useful.size();
1294 
1295   if (l_nodes != l_nodes_by_walk) {
1296     if (_log != NULL) {
1297       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
1298       _log->stamp();
1299       _log->end_head();
1300     }
1301     VectorSet& useful_member_set = useful.member_set();
1302     int last_idx = l_nodes_by_walk;
1303     for (int i = 0; i < last_idx; i++) {
1304       if (useful_member_set.test(i)) {
1305         if (_dead_node_list.test(i)) {
1306           if (_log != NULL) {
1307             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
1308           }
1309           if (PrintIdealNodeCount) {
1310             // Print the log message to tty
1311               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
1312               useful.at(i)->dump();
1313           }
1314         }
1315       }
1316       else if (! _dead_node_list.test(i)) {
1317         if (_log != NULL) {
1318           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
1319         }
1320         if (PrintIdealNodeCount) {
1321           // Print the log message to tty
1322           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
1323         }
1324       }
1325     }
1326     if (_log != NULL) {
1327       _log->tail("mismatched_nodes");
1328     }
1329   }
1330 }
1331 void Compile::record_modified_node(Node* n) {
1332   if (_modified_nodes != NULL && !_inlining_incrementally &&
1333       n->outcnt() != 0 && !n->is_Con()) {
1334     _modified_nodes->push(n);
1335   }
1336 }
1337 
1338 void Compile::remove_modified_node(Node* n) {
1339   if (_modified_nodes != NULL) {
1340     _modified_nodes->remove(n);
1341   }
1342 }
1343 #endif
1344 
1345 #ifndef PRODUCT
1346 void Compile::verify_top(Node* tn) const {
1347   if (tn != NULL) {
1348     assert(tn->is_Con(), "top node must be a constant");
1349     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1350     assert(tn->in(0) != NULL, "must have live top node");
1351   }
1352 }
1353 #endif
1354 
1355 
1356 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1357 
1358 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1359   guarantee(arr != NULL, "");
1360   int num_blocks = arr->length();
1361   if (grow_by < num_blocks)  grow_by = num_blocks;
1362   int num_notes = grow_by * _node_notes_block_size;
1363   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1364   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1365   while (num_notes > 0) {
1366     arr->append(notes);
1367     notes     += _node_notes_block_size;
1368     num_notes -= _node_notes_block_size;
1369   }
1370   assert(num_notes == 0, "exact multiple, please");
1371 }
1372 
1373 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1374   if (source == NULL || dest == NULL)  return false;
1375 
1376   if (dest->is_Con())
1377     return false;               // Do not push debug info onto constants.
1378 
1379 #ifdef ASSERT
1380   // Leave a bread crumb trail pointing to the original node:
1381   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1382     dest->set_debug_orig(source);
1383   }
1384 #endif
1385 
1386   if (node_note_array() == NULL)
1387     return false;               // Not collecting any notes now.
1388 
1389   // This is a copy onto a pre-existing node, which may already have notes.
1390   // If both nodes have notes, do not overwrite any pre-existing notes.
1391   Node_Notes* source_notes = node_notes_at(source->_idx);
1392   if (source_notes == NULL || source_notes->is_clear())  return false;
1393   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
1394   if (dest_notes == NULL || dest_notes->is_clear()) {
1395     return set_node_notes_at(dest->_idx, source_notes);
1396   }
1397 
1398   Node_Notes merged_notes = (*source_notes);
1399   // The order of operations here ensures that dest notes will win...
1400   merged_notes.update_from(dest_notes);
1401   return set_node_notes_at(dest->_idx, &merged_notes);
1402 }
1403 
1404 
1405 //--------------------------allow_range_check_smearing-------------------------
1406 // Gating condition for coalescing similar range checks.
1407 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1408 // single covering check that is at least as strong as any of them.
1409 // If the optimization succeeds, the simplified (strengthened) range check
1410 // will always succeed.  If it fails, we will deopt, and then give up
1411 // on the optimization.
1412 bool Compile::allow_range_check_smearing() const {
1413   // If this method has already thrown a range-check,
1414   // assume it was because we already tried range smearing
1415   // and it failed.
1416   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1417   return !already_trapped;
1418 }
1419 
1420 
1421 //------------------------------flatten_alias_type-----------------------------
1422 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1423   int offset = tj->offset();
1424   TypePtr::PTR ptr = tj->ptr();
1425 
1426   // Known instance (scalarizable allocation) alias only with itself.
1427   bool is_known_inst = tj->isa_oopptr() != NULL &&
1428                        tj->is_oopptr()->is_known_instance();
1429 
1430   // Process weird unsafe references.
1431   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1432     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
1433     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1434     tj = TypeOopPtr::BOTTOM;
1435     ptr = tj->ptr();
1436     offset = tj->offset();
1437   }
1438 
1439   // Array pointers need some flattening
1440   const TypeAryPtr *ta = tj->isa_aryptr();
1441   if (ta && ta->is_stable()) {
1442     // Erase stability property for alias analysis.
1443     tj = ta = ta->cast_to_stable(false);
1444   }
1445   if( ta && is_known_inst ) {
1446     if ( offset != Type::OffsetBot &&
1447          offset > arrayOopDesc::length_offset_in_bytes() ) {
1448       offset = Type::OffsetBot; // Flatten constant access into array body only
1449       tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
1450     }
1451   } else if( ta && _AliasLevel >= 2 ) {
1452     // For arrays indexed by constant indices, we flatten the alias
1453     // space to include all of the array body.  Only the header, klass
1454     // and array length can be accessed un-aliased.
1455     if( offset != Type::OffsetBot ) {
1456       if( ta->const_oop() ) { // MethodData* or Method*
1457         offset = Type::OffsetBot;   // Flatten constant access into array body
1458         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
1459       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1460         // range is OK as-is.
1461         tj = ta = TypeAryPtr::RANGE;
1462       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1463         tj = TypeInstPtr::KLASS; // all klass loads look alike
1464         ta = TypeAryPtr::RANGE; // generic ignored junk
1465         ptr = TypePtr::BotPTR;
1466       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1467         tj = TypeInstPtr::MARK;
1468         ta = TypeAryPtr::RANGE; // generic ignored junk
1469         ptr = TypePtr::BotPTR;
1470       } else {                  // Random constant offset into array body
1471         offset = Type::OffsetBot;   // Flatten constant access into array body
1472         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
1473       }
1474     }
1475     // Arrays of fixed size alias with arrays of unknown size.
1476     if (ta->size() != TypeInt::POS) {
1477       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1478       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
1479     }
1480     // Arrays of known objects become arrays of unknown objects.
1481     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1482       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1483       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1484     }
1485     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1486       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1487       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1488     }
1489     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1490     // cannot be distinguished by bytecode alone.
1491     if (ta->elem() == TypeInt::BOOL) {
1492       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1493       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1494       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
1495     }
1496     // During the 2nd round of IterGVN, NotNull castings are removed.
1497     // Make sure the Bottom and NotNull variants alias the same.
1498     // Also, make sure exact and non-exact variants alias the same.
1499     if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != NULL) {
1500       tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
1501     }
1502   }
1503 
1504   // Oop pointers need some flattening
1505   const TypeInstPtr *to = tj->isa_instptr();
1506   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1507     ciInstanceKlass *k = to->klass()->as_instance_klass();
1508     if( ptr == TypePtr::Constant ) {
1509       if (to->klass() != ciEnv::current()->Class_klass() ||
1510           offset < k->size_helper() * wordSize) {
1511         // No constant oop pointers (such as Strings); they alias with
1512         // unknown strings.
1513         assert(!is_known_inst, "not scalarizable allocation");
1514         tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1515       }
1516     } else if( is_known_inst ) {
1517       tj = to; // Keep NotNull and klass_is_exact for instance type
1518     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1519       // During the 2nd round of IterGVN, NotNull castings are removed.
1520       // Make sure the Bottom and NotNull variants alias the same.
1521       // Also, make sure exact and non-exact variants alias the same.
1522       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1523     }
1524     if (to->speculative() != NULL) {
1525       tj = to = TypeInstPtr::make(to->ptr(),to->klass(),to->klass_is_exact(),to->const_oop(),to->offset(), to->instance_id());
1526     }
1527     // Canonicalize the holder of this field
1528     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1529       // First handle header references such as a LoadKlassNode, even if the
1530       // object's klass is unloaded at compile time (4965979).
1531       if (!is_known_inst) { // Do it only for non-instance types
1532         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
1533       }
1534     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1535       // Static fields are in the space above the normal instance
1536       // fields in the java.lang.Class instance.
1537       if (to->klass() != ciEnv::current()->Class_klass()) {
1538         to = NULL;
1539         tj = TypeOopPtr::BOTTOM;
1540         offset = tj->offset();
1541       }
1542     } else {
1543       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1544       if (!k->equals(canonical_holder) || tj->offset() != offset) {
1545         if( is_known_inst ) {
1546           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
1547         } else {
1548           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
1549         }
1550       }
1551     }
1552   }
1553 
1554   // Klass pointers to object array klasses need some flattening
1555   const TypeKlassPtr *tk = tj->isa_klassptr();
1556   if( tk ) {
1557     // If we are referencing a field within a Klass, we need
1558     // to assume the worst case of an Object.  Both exact and
1559     // inexact types must flatten to the same alias class so
1560     // use NotNull as the PTR.
1561     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1562 
1563       tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
1564                                    TypeKlassPtr::OBJECT->klass(),
1565                                    offset);
1566     }
1567 
1568     ciKlass* klass = tk->klass();
1569     if( klass->is_obj_array_klass() ) {
1570       ciKlass* k = TypeAryPtr::OOPS->klass();
1571       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
1572         k = TypeInstPtr::BOTTOM->klass();
1573       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
1574     }
1575 
1576     // Check for precise loads from the primary supertype array and force them
1577     // to the supertype cache alias index.  Check for generic array loads from
1578     // the primary supertype array and also force them to the supertype cache
1579     // alias index.  Since the same load can reach both, we need to merge
1580     // these 2 disparate memories into the same alias class.  Since the
1581     // primary supertype array is read-only, there's no chance of confusion
1582     // where we bypass an array load and an array store.
1583     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1584     if (offset == Type::OffsetBot ||
1585         (offset >= primary_supers_offset &&
1586          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1587         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1588       offset = in_bytes(Klass::secondary_super_cache_offset());
1589       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
1590     }
1591   }
1592 
1593   // Flatten all Raw pointers together.
1594   if (tj->base() == Type::RawPtr)
1595     tj = TypeRawPtr::BOTTOM;
1596 
1597   if (tj->base() == Type::AnyPtr)
1598     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
1599 
1600   // Flatten all to bottom for now
1601   switch( _AliasLevel ) {
1602   case 0:
1603     tj = TypePtr::BOTTOM;
1604     break;
1605   case 1:                       // Flatten to: oop, static, field or array
1606     switch (tj->base()) {
1607     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
1608     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
1609     case Type::AryPtr:   // do not distinguish arrays at all
1610     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
1611     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1612     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
1613     default: ShouldNotReachHere();
1614     }
1615     break;
1616   case 2:                       // No collapsing at level 2; keep all splits
1617   case 3:                       // No collapsing at level 3; keep all splits
1618     break;
1619   default:
1620     Unimplemented();
1621   }
1622 
1623   offset = tj->offset();
1624   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1625 
1626   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1627           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1628           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1629           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1630           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1631           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1632           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr)  ,
1633           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1634   assert( tj->ptr() != TypePtr::TopPTR &&
1635           tj->ptr() != TypePtr::AnyNull &&
1636           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1637 //    assert( tj->ptr() != TypePtr::Constant ||
1638 //            tj->base() == Type::RawPtr ||
1639 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
1640 
1641   return tj;
1642 }
1643 
1644 void Compile::AliasType::Init(int i, const TypePtr* at) {
1645   _index = i;
1646   _adr_type = at;
1647   _field = NULL;
1648   _element = NULL;
1649   _is_rewritable = true; // default
1650   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1651   if (atoop != NULL && atoop->is_known_instance()) {
1652     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1653     _general_index = Compile::current()->get_alias_index(gt);
1654   } else {
1655     _general_index = 0;
1656   }
1657 }
1658 
1659 BasicType Compile::AliasType::basic_type() const {
1660   if (element() != NULL) {
1661     const Type* element = adr_type()->is_aryptr()->elem();
1662     return element->isa_narrowoop() ? T_OBJECT : element->array_element_basic_type();
1663   } if (field() != NULL) {
1664     return field()->layout_type();
1665   } else {
1666     return T_ILLEGAL; // unknown
1667   }
1668 }
1669 
1670 //---------------------------------print_on------------------------------------
1671 #ifndef PRODUCT
1672 void Compile::AliasType::print_on(outputStream* st) {
1673   if (index() < 10)
1674         st->print("@ <%d> ", index());
1675   else  st->print("@ <%d>",  index());
1676   st->print(is_rewritable() ? "   " : " RO");
1677   int offset = adr_type()->offset();
1678   if (offset == Type::OffsetBot)
1679         st->print(" +any");
1680   else  st->print(" +%-3d", offset);
1681   st->print(" in ");
1682   adr_type()->dump_on(st);
1683   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1684   if (field() != NULL && tjp) {
1685     if (tjp->klass()  != field()->holder() ||
1686         tjp->offset() != field()->offset_in_bytes()) {
1687       st->print(" != ");
1688       field()->print();
1689       st->print(" ***");
1690     }
1691   }
1692 }
1693 
1694 void print_alias_types() {
1695   Compile* C = Compile::current();
1696   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1697   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1698     C->alias_type(idx)->print_on(tty);
1699     tty->cr();
1700   }
1701 }
1702 #endif
1703 
1704 
1705 //----------------------------probe_alias_cache--------------------------------
1706 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1707   intptr_t key = (intptr_t) adr_type;
1708   key ^= key >> logAliasCacheSize;
1709   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1710 }
1711 
1712 
1713 //-----------------------------grow_alias_types--------------------------------
1714 void Compile::grow_alias_types() {
1715   const int old_ats  = _max_alias_types; // how many before?
1716   const int new_ats  = old_ats;          // how many more?
1717   const int grow_ats = old_ats+new_ats;  // how many now?
1718   _max_alias_types = grow_ats;
1719   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1720   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1721   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1722   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
1723 }
1724 
1725 
1726 //--------------------------------find_alias_type------------------------------
1727 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1728   if (_AliasLevel == 0)
1729     return alias_type(AliasIdxBot);
1730 
1731   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1732   if (ace->_adr_type == adr_type) {
1733     return alias_type(ace->_index);
1734   }
1735 
1736   // Handle special cases.
1737   if (adr_type == NULL)             return alias_type(AliasIdxTop);
1738   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
1739 
1740   // Do it the slow way.
1741   const TypePtr* flat = flatten_alias_type(adr_type);
1742 
1743 #ifdef ASSERT
1744   {
1745     ResourceMark rm;
1746     assert(flat == flatten_alias_type(flat), "not idempotent: adr_type = %s; flat = %s => %s",
1747            Type::str(adr_type), Type::str(flat), Type::str(flatten_alias_type(flat)));
1748     assert(flat != TypePtr::BOTTOM, "cannot alias-analyze an untyped ptr: adr_type = %s",
1749            Type::str(adr_type));
1750     if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1751       const TypeOopPtr* foop = flat->is_oopptr();
1752       // Scalarizable allocations have exact klass always.
1753       bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1754       const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1755       assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type: foop = %s; xoop = %s",
1756              Type::str(foop), Type::str(xoop));
1757     }
1758   }
1759 #endif
1760 
1761   int idx = AliasIdxTop;
1762   for (int i = 0; i < num_alias_types(); i++) {
1763     if (alias_type(i)->adr_type() == flat) {
1764       idx = i;
1765       break;
1766     }
1767   }
1768 
1769   if (idx == AliasIdxTop) {
1770     if (no_create)  return NULL;
1771     // Grow the array if necessary.
1772     if (_num_alias_types == _max_alias_types)  grow_alias_types();
1773     // Add a new alias type.
1774     idx = _num_alias_types++;
1775     _alias_types[idx]->Init(idx, flat);
1776     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
1777     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
1778     if (flat->isa_instptr()) {
1779       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1780           && flat->is_instptr()->klass() == env()->Class_klass())
1781         alias_type(idx)->set_rewritable(false);
1782     }
1783     if (flat->isa_aryptr()) {
1784 #ifdef ASSERT
1785       const int header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1786       // (T_BYTE has the weakest alignment and size restrictions...)
1787       assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
1788 #endif
1789       if (flat->offset() == TypePtr::OffsetBot) {
1790         alias_type(idx)->set_element(flat->is_aryptr()->elem());
1791       }
1792     }
1793     if (flat->isa_klassptr()) {
1794       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1795         alias_type(idx)->set_rewritable(false);
1796       if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
1797         alias_type(idx)->set_rewritable(false);
1798       if (flat->offset() == in_bytes(Klass::access_flags_offset()))
1799         alias_type(idx)->set_rewritable(false);
1800       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1801         alias_type(idx)->set_rewritable(false);
1802     }
1803     // %%% (We would like to finalize JavaThread::threadObj_offset(),
1804     // but the base pointer type is not distinctive enough to identify
1805     // references into JavaThread.)
1806 
1807     // Check for final fields.
1808     const TypeInstPtr* tinst = flat->isa_instptr();
1809     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1810       ciField* field;
1811       if (tinst->const_oop() != NULL &&
1812           tinst->klass() == ciEnv::current()->Class_klass() &&
1813           tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
1814         // static field
1815         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1816         field = k->get_field_by_offset(tinst->offset(), true);
1817       } else {
1818         ciInstanceKlass *k = tinst->klass()->as_instance_klass();
1819         field = k->get_field_by_offset(tinst->offset(), false);
1820       }
1821       assert(field == NULL ||
1822              original_field == NULL ||
1823              (field->holder() == original_field->holder() &&
1824               field->offset() == original_field->offset() &&
1825               field->is_static() == original_field->is_static()), "wrong field?");
1826       // Set field() and is_rewritable() attributes.
1827       if (field != NULL)  alias_type(idx)->set_field(field);
1828     }
1829   }
1830 
1831   // Fill the cache for next time.
1832   ace->_adr_type = adr_type;
1833   ace->_index    = idx;
1834   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
1835 
1836   // Might as well try to fill the cache for the flattened version, too.
1837   AliasCacheEntry* face = probe_alias_cache(flat);
1838   if (face->_adr_type == NULL) {
1839     face->_adr_type = flat;
1840     face->_index    = idx;
1841     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1842   }
1843 
1844   return alias_type(idx);
1845 }
1846 
1847 
1848 Compile::AliasType* Compile::alias_type(ciField* field) {
1849   const TypeOopPtr* t;
1850   if (field->is_static())
1851     t = TypeInstPtr::make(field->holder()->java_mirror());
1852   else
1853     t = TypeOopPtr::make_from_klass_raw(field->holder());
1854   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1855   assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
1856   return atp;
1857 }
1858 
1859 
1860 //------------------------------have_alias_type--------------------------------
1861 bool Compile::have_alias_type(const TypePtr* adr_type) {
1862   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1863   if (ace->_adr_type == adr_type) {
1864     return true;
1865   }
1866 
1867   // Handle special cases.
1868   if (adr_type == NULL)             return true;
1869   if (adr_type == TypePtr::BOTTOM)  return true;
1870 
1871   return find_alias_type(adr_type, true, NULL) != NULL;
1872 }
1873 
1874 //-----------------------------must_alias--------------------------------------
1875 // True if all values of the given address type are in the given alias category.
1876 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1877   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1878   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
1879   if (alias_idx == AliasIdxTop)         return false; // the empty category
1880   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1881 
1882   // the only remaining possible overlap is identity
1883   int adr_idx = get_alias_index(adr_type);
1884   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1885   assert(adr_idx == alias_idx ||
1886          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1887           && adr_type                       != TypeOopPtr::BOTTOM),
1888          "should not be testing for overlap with an unsafe pointer");
1889   return adr_idx == alias_idx;
1890 }
1891 
1892 //------------------------------can_alias--------------------------------------
1893 // True if any values of the given address type are in the given alias category.
1894 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1895   if (alias_idx == AliasIdxTop)         return false; // the empty category
1896   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
1897   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1898   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
1899 
1900   // the only remaining possible overlap is identity
1901   int adr_idx = get_alias_index(adr_type);
1902   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1903   return adr_idx == alias_idx;
1904 }
1905 
1906 
1907 
1908 //---------------------------pop_warm_call-------------------------------------
1909 WarmCallInfo* Compile::pop_warm_call() {
1910   WarmCallInfo* wci = _warm_calls;
1911   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
1912   return wci;
1913 }
1914 
1915 //----------------------------Inline_Warm--------------------------------------
1916 int Compile::Inline_Warm() {
1917   // If there is room, try to inline some more warm call sites.
1918   // %%% Do a graph index compaction pass when we think we're out of space?
1919   if (!InlineWarmCalls)  return 0;
1920 
1921   int calls_made_hot = 0;
1922   int room_to_grow   = NodeCountInliningCutoff - unique();
1923   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1924   int amount_grown   = 0;
1925   WarmCallInfo* call;
1926   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1927     int est_size = (int)call->size();
1928     if (est_size > (room_to_grow - amount_grown)) {
1929       // This one won't fit anyway.  Get rid of it.
1930       call->make_cold();
1931       continue;
1932     }
1933     call->make_hot();
1934     calls_made_hot++;
1935     amount_grown   += est_size;
1936     amount_to_grow -= est_size;
1937   }
1938 
1939   if (calls_made_hot > 0)  set_major_progress();
1940   return calls_made_hot;
1941 }
1942 
1943 
1944 //----------------------------Finish_Warm--------------------------------------
1945 void Compile::Finish_Warm() {
1946   if (!InlineWarmCalls)  return;
1947   if (failing())  return;
1948   if (warm_calls() == NULL)  return;
1949 
1950   // Clean up loose ends, if we are out of space for inlining.
1951   WarmCallInfo* call;
1952   while ((call = pop_warm_call()) != NULL) {
1953     call->make_cold();
1954   }
1955 }
1956 
1957 //---------------------cleanup_loop_predicates-----------------------
1958 // Remove the opaque nodes that protect the predicates so that all unused
1959 // checks and uncommon_traps will be eliminated from the ideal graph
1960 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1961   if (predicate_count()==0) return;
1962   for (int i = predicate_count(); i > 0; i--) {
1963     Node * n = predicate_opaque1_node(i-1);
1964     assert(n->Opcode() == Op_Opaque1, "must be");
1965     igvn.replace_node(n, n->in(1));
1966   }
1967   assert(predicate_count()==0, "should be clean!");
1968 }
1969 
1970 void Compile::add_range_check_cast(Node* n) {
1971   assert(n->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1972   assert(!_range_check_casts->contains(n), "duplicate entry in range check casts");
1973   _range_check_casts->append(n);
1974 }
1975 
1976 // Remove all range check dependent CastIINodes.
1977 void Compile::remove_range_check_casts(PhaseIterGVN &igvn) {
1978   for (int i = range_check_cast_count(); i > 0; i--) {
1979     Node* cast = range_check_cast_node(i-1);
1980     assert(cast->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1981     igvn.replace_node(cast, cast->in(1));
1982   }
1983   assert(range_check_cast_count() == 0, "should be empty");
1984 }
1985 
1986 void Compile::add_opaque4_node(Node* n) {
1987   assert(n->Opcode() == Op_Opaque4, "Opaque4 only");
1988   assert(!_opaque4_nodes->contains(n), "duplicate entry in Opaque4 list");
1989   _opaque4_nodes->append(n);
1990 }
1991 
1992 // Remove all Opaque4 nodes.
1993 void Compile::remove_opaque4_nodes(PhaseIterGVN &igvn) {
1994   for (int i = opaque4_count(); i > 0; i--) {
1995     Node* opaq = opaque4_node(i-1);
1996     assert(opaq->Opcode() == Op_Opaque4, "Opaque4 only");
1997     igvn.replace_node(opaq, opaq->in(2));
1998   }
1999   assert(opaque4_count() == 0, "should be empty");
2000 }
2001 
2002 // StringOpts and late inlining of string methods
2003 void Compile::inline_string_calls(bool parse_time) {
2004   {
2005     // remove useless nodes to make the usage analysis simpler
2006     ResourceMark rm;
2007     PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2008   }
2009 
2010   {
2011     ResourceMark rm;
2012     print_method(PHASE_BEFORE_STRINGOPTS, 3);
2013     PhaseStringOpts pso(initial_gvn(), for_igvn());
2014     print_method(PHASE_AFTER_STRINGOPTS, 3);
2015   }
2016 
2017   // now inline anything that we skipped the first time around
2018   if (!parse_time) {
2019     _late_inlines_pos = _late_inlines.length();
2020   }
2021 
2022   while (_string_late_inlines.length() > 0) {
2023     CallGenerator* cg = _string_late_inlines.pop();
2024     cg->do_late_inline();
2025     if (failing())  return;
2026   }
2027   _string_late_inlines.trunc_to(0);
2028 }
2029 
2030 // Late inlining of boxing methods
2031 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
2032   if (_boxing_late_inlines.length() > 0) {
2033     assert(has_boxed_value(), "inconsistent");
2034 
2035     PhaseGVN* gvn = initial_gvn();
2036     set_inlining_incrementally(true);
2037 
2038     assert( igvn._worklist.size() == 0, "should be done with igvn" );
2039     for_igvn()->clear();
2040     gvn->replace_with(&igvn);
2041 
2042     _late_inlines_pos = _late_inlines.length();
2043 
2044     while (_boxing_late_inlines.length() > 0) {
2045       CallGenerator* cg = _boxing_late_inlines.pop();
2046       cg->do_late_inline();
2047       if (failing())  return;
2048     }
2049     _boxing_late_inlines.trunc_to(0);
2050 
2051     {
2052       ResourceMark rm;
2053       PhaseRemoveUseless pru(gvn, for_igvn());
2054     }
2055 
2056     igvn = PhaseIterGVN(gvn);
2057     igvn.optimize();
2058 
2059     set_inlining_progress(false);
2060     set_inlining_incrementally(false);
2061   }
2062 }
2063 
2064 void Compile::inline_incrementally_one(PhaseIterGVN& igvn) {
2065   assert(IncrementalInline, "incremental inlining should be on");
2066   PhaseGVN* gvn = initial_gvn();
2067 
2068   set_inlining_progress(false);
2069   for_igvn()->clear();
2070   gvn->replace_with(&igvn);
2071 
2072   {
2073     TracePhase tp("incrementalInline_inline", &timers[_t_incrInline_inline]);
2074     int i = 0;
2075     for (; i <_late_inlines.length() && !inlining_progress(); i++) {
2076       CallGenerator* cg = _late_inlines.at(i);
2077       _late_inlines_pos = i+1;
2078       cg->do_late_inline();
2079       if (failing())  return;
2080     }
2081     int j = 0;
2082     for (; i < _late_inlines.length(); i++, j++) {
2083       _late_inlines.at_put(j, _late_inlines.at(i));
2084     }
2085     _late_inlines.trunc_to(j);
2086   }
2087 
2088   {
2089     TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2090     ResourceMark rm;
2091     PhaseRemoveUseless pru(gvn, for_igvn());
2092   }
2093 
2094   {
2095     TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2096     igvn = PhaseIterGVN(gvn);
2097   }
2098 }
2099 
2100 // Perform incremental inlining until bound on number of live nodes is reached
2101 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
2102   TracePhase tp("incrementalInline", &timers[_t_incrInline]);
2103 
2104   PhaseGVN* gvn = initial_gvn();
2105 
2106   set_inlining_incrementally(true);
2107   set_inlining_progress(true);
2108   uint low_live_nodes = 0;
2109 
2110   while(inlining_progress() && _late_inlines.length() > 0) {
2111 
2112     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2113       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
2114         TracePhase tp("incrementalInline_ideal", &timers[_t_incrInline_ideal]);
2115         // PhaseIdealLoop is expensive so we only try it once we are
2116         // out of live nodes and we only try it again if the previous
2117         // helped got the number of nodes down significantly
2118         PhaseIdealLoop ideal_loop(igvn, LoopOptsNone);
2119         if (failing())  return;
2120         low_live_nodes = live_nodes();
2121         _major_progress = true;
2122       }
2123 
2124       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2125         break;
2126       }
2127     }
2128 
2129     inline_incrementally_one(igvn);
2130 
2131     if (failing())  return;
2132 
2133     {
2134       TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2135       igvn.optimize();
2136     }
2137 
2138     if (failing())  return;
2139   }
2140 
2141   assert( igvn._worklist.size() == 0, "should be done with igvn" );
2142 
2143   if (_string_late_inlines.length() > 0) {
2144     assert(has_stringbuilder(), "inconsistent");
2145     for_igvn()->clear();
2146     initial_gvn()->replace_with(&igvn);
2147 
2148     inline_string_calls(false);
2149 
2150     if (failing())  return;
2151 
2152     {
2153       TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2154       ResourceMark rm;
2155       PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2156     }
2157 
2158     {
2159       TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2160       igvn = PhaseIterGVN(gvn);
2161       igvn.optimize();
2162     }
2163   }
2164 
2165   set_inlining_incrementally(false);
2166 }
2167 
2168 
2169 bool Compile::optimize_loops(int& loop_opts_cnt, PhaseIterGVN& igvn, LoopOptsMode mode) {
2170   if(loop_opts_cnt > 0) {
2171     debug_only( int cnt = 0; );
2172     while(major_progress() && (loop_opts_cnt > 0)) {
2173       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2174       assert( cnt++ < 40, "infinite cycle in loop optimization" );
2175       PhaseIdealLoop ideal_loop(igvn, mode);
2176       loop_opts_cnt--;
2177       if (failing())  return false;
2178       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
2179     }
2180   }
2181   return true;
2182 }
2183 
2184 //------------------------------Optimize---------------------------------------
2185 // Given a graph, optimize it.
2186 void Compile::Optimize() {
2187   TracePhase tp("optimizer", &timers[_t_optimizer]);
2188 
2189 #ifndef PRODUCT
2190   if (_directive->BreakAtCompileOption) {
2191     BREAKPOINT;
2192   }
2193 
2194 #endif
2195 
2196 #ifdef ASSERT
2197   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2198   bs->verify_gc_barriers(true);
2199 #endif
2200 
2201   ResourceMark rm;
2202   int          loop_opts_cnt;
2203 
2204   print_inlining_reinit();
2205 
2206   NOT_PRODUCT( verify_graph_edges(); )
2207 
2208   print_method(PHASE_AFTER_PARSING);
2209 
2210  {
2211   // Iterative Global Value Numbering, including ideal transforms
2212   // Initialize IterGVN with types and values from parse-time GVN
2213   PhaseIterGVN igvn(initial_gvn());
2214 #ifdef ASSERT
2215   _modified_nodes = new (comp_arena()) Unique_Node_List(comp_arena());
2216 #endif
2217   {
2218     TracePhase tp("iterGVN", &timers[_t_iterGVN]);
2219     igvn.optimize();
2220   }
2221 
2222   if (failing())  return;
2223 
2224   print_method(PHASE_ITER_GVN1, 2);
2225 
2226   inline_incrementally(igvn);
2227 
2228   print_method(PHASE_INCREMENTAL_INLINE, 2);
2229 
2230   if (failing())  return;
2231 
2232   if (eliminate_boxing()) {
2233     // Inline valueOf() methods now.
2234     inline_boxing_calls(igvn);
2235 
2236     if (AlwaysIncrementalInline) {
2237       inline_incrementally(igvn);
2238     }
2239 
2240     print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
2241 
2242     if (failing())  return;
2243   }
2244 
2245   // Remove the speculative part of types and clean up the graph from
2246   // the extra CastPP nodes whose only purpose is to carry them. Do
2247   // that early so that optimizations are not disrupted by the extra
2248   // CastPP nodes.
2249   remove_speculative_types(igvn);
2250 
2251   // No more new expensive nodes will be added to the list from here
2252   // so keep only the actual candidates for optimizations.
2253   cleanup_expensive_nodes(igvn);
2254 
2255   if (!failing() && RenumberLiveNodes && live_nodes() + NodeLimitFudgeFactor < unique()) {
2256     Compile::TracePhase tp("", &timers[_t_renumberLive]);
2257     initial_gvn()->replace_with(&igvn);
2258     for_igvn()->clear();
2259     Unique_Node_List new_worklist(C->comp_arena());
2260     {
2261       ResourceMark rm;
2262       PhaseRenumberLive prl = PhaseRenumberLive(initial_gvn(), for_igvn(), &new_worklist);
2263     }
2264     set_for_igvn(&new_worklist);
2265     igvn = PhaseIterGVN(initial_gvn());
2266     igvn.optimize();
2267   }
2268 
2269   // Perform escape analysis
2270   if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
2271     if (has_loops()) {
2272       // Cleanup graph (remove dead nodes).
2273       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2274       PhaseIdealLoop ideal_loop(igvn, LoopOptsNone);
2275       if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
2276       if (failing())  return;
2277     }
2278     ConnectionGraph::do_analysis(this, &igvn);
2279 
2280     if (failing())  return;
2281 
2282     // Optimize out fields loads from scalar replaceable allocations.
2283     igvn.optimize();
2284     print_method(PHASE_ITER_GVN_AFTER_EA, 2);
2285 
2286     if (failing())  return;
2287 
2288     if (congraph() != NULL && macro_count() > 0) {
2289       TracePhase tp("macroEliminate", &timers[_t_macroEliminate]);
2290       PhaseMacroExpand mexp(igvn);
2291       mexp.eliminate_macro_nodes();
2292       igvn.set_delay_transform(false);
2293 
2294       igvn.optimize();
2295       print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
2296 
2297       if (failing())  return;
2298     }
2299   }
2300 
2301   // Loop transforms on the ideal graph.  Range Check Elimination,
2302   // peeling, unrolling, etc.
2303 
2304   // Set loop opts counter
2305   loop_opts_cnt = num_loop_opts();
2306   if((loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
2307     {
2308       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2309       PhaseIdealLoop ideal_loop(igvn, LoopOptsDefault);
2310       loop_opts_cnt--;
2311       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
2312       if (failing())  return;
2313     }
2314     // Loop opts pass if partial peeling occurred in previous pass
2315     if(PartialPeelLoop && major_progress() && (loop_opts_cnt > 0)) {
2316       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2317       PhaseIdealLoop ideal_loop(igvn, LoopOptsSkipSplitIf);
2318       loop_opts_cnt--;
2319       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
2320       if (failing())  return;
2321     }
2322     // Loop opts pass for loop-unrolling before CCP
2323     if(major_progress() && (loop_opts_cnt > 0)) {
2324       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2325       PhaseIdealLoop ideal_loop(igvn, LoopOptsSkipSplitIf);
2326       loop_opts_cnt--;
2327       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
2328     }
2329     if (!failing()) {
2330       // Verify that last round of loop opts produced a valid graph
2331       TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2332       PhaseIdealLoop::verify(igvn);
2333     }
2334   }
2335   if (failing())  return;
2336 
2337   // Conditional Constant Propagation;
2338   PhaseCCP ccp( &igvn );
2339   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
2340   {
2341     TracePhase tp("ccp", &timers[_t_ccp]);
2342     ccp.do_transform();
2343   }
2344   print_method(PHASE_CPP1, 2);
2345 
2346   assert( true, "Break here to ccp.dump_old2new_map()");
2347 
2348   // Iterative Global Value Numbering, including ideal transforms
2349   {
2350     TracePhase tp("iterGVN2", &timers[_t_iterGVN2]);
2351     igvn = ccp;
2352     igvn.optimize();
2353   }
2354 
2355   print_method(PHASE_ITER_GVN2, 2);
2356 
2357   if (failing())  return;
2358 
2359   // Loop transforms on the ideal graph.  Range Check Elimination,
2360   // peeling, unrolling, etc.
2361   if (!optimize_loops(loop_opts_cnt, igvn, LoopOptsDefault)) {
2362     return;
2363   }
2364 
2365 #if INCLUDE_ZGC
2366   if (UseZGC) {
2367     ZBarrierSetC2::find_dominating_barriers(igvn);
2368   }
2369 #endif
2370 
2371   if (failing())  return;
2372 
2373   // Ensure that major progress is now clear
2374   C->clear_major_progress();
2375 
2376   {
2377     // Verify that all previous optimizations produced a valid graph
2378     // at least to this point, even if no loop optimizations were done.
2379     TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2380     PhaseIdealLoop::verify(igvn);
2381   }
2382 
2383   if (range_check_cast_count() > 0) {
2384     // No more loop optimizations. Remove all range check dependent CastIINodes.
2385     C->remove_range_check_casts(igvn);
2386     igvn.optimize();
2387   }
2388 
2389 #ifdef ASSERT
2390   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2391   bs->verify_gc_barriers(false);
2392 #endif
2393 
2394   {
2395     TracePhase tp("macroExpand", &timers[_t_macroExpand]);
2396     PhaseMacroExpand  mex(igvn);
2397     print_method(PHASE_BEFORE_MACRO_EXPANSION, 2);
2398     if (mex.expand_macro_nodes()) {
2399       assert(failing(), "must bail out w/ explicit message");
2400       return;
2401     }
2402   }
2403 
2404   if (opaque4_count() > 0) {
2405     C->remove_opaque4_nodes(igvn);
2406     igvn.optimize();
2407   }
2408 
2409   DEBUG_ONLY( _modified_nodes = NULL; )
2410  } // (End scope of igvn; run destructor if necessary for asserts.)
2411 
2412  process_print_inlining();
2413  // A method with only infinite loops has no edges entering loops from root
2414  {
2415    TracePhase tp("graphReshape", &timers[_t_graphReshaping]);
2416    if (final_graph_reshaping()) {
2417      assert(failing(), "must bail out w/ explicit message");
2418      return;
2419    }
2420  }
2421 
2422  print_method(PHASE_OPTIMIZE_FINISHED, 2);
2423 }
2424 
2425 
2426 //------------------------------Code_Gen---------------------------------------
2427 // Given a graph, generate code for it
2428 void Compile::Code_Gen() {
2429   if (failing()) {
2430     return;
2431   }
2432 
2433   // Perform instruction selection.  You might think we could reclaim Matcher
2434   // memory PDQ, but actually the Matcher is used in generating spill code.
2435   // Internals of the Matcher (including some VectorSets) must remain live
2436   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
2437   // set a bit in reclaimed memory.
2438 
2439   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2440   // nodes.  Mapping is only valid at the root of each matched subtree.
2441   NOT_PRODUCT( verify_graph_edges(); )
2442 
2443   Matcher matcher;
2444   _matcher = &matcher;
2445   {
2446     TracePhase tp("matcher", &timers[_t_matcher]);
2447     matcher.match();
2448   }
2449   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2450   // nodes.  Mapping is only valid at the root of each matched subtree.
2451   NOT_PRODUCT( verify_graph_edges(); )
2452 
2453   // If you have too many nodes, or if matching has failed, bail out
2454   check_node_count(0, "out of nodes matching instructions");
2455   if (failing()) {
2456     return;
2457   }
2458 
2459   print_method(PHASE_MATCHING, 2);
2460 
2461   // Build a proper-looking CFG
2462   PhaseCFG cfg(node_arena(), root(), matcher);
2463   _cfg = &cfg;
2464   {
2465     TracePhase tp("scheduler", &timers[_t_scheduler]);
2466     bool success = cfg.do_global_code_motion();
2467     if (!success) {
2468       return;
2469     }
2470 
2471     print_method(PHASE_GLOBAL_CODE_MOTION, 2);
2472     NOT_PRODUCT( verify_graph_edges(); )
2473     debug_only( cfg.verify(); )
2474   }
2475 
2476   PhaseChaitin regalloc(unique(), cfg, matcher, false);
2477   _regalloc = &regalloc;
2478   {
2479     TracePhase tp("regalloc", &timers[_t_registerAllocation]);
2480     // Perform register allocation.  After Chaitin, use-def chains are
2481     // no longer accurate (at spill code) and so must be ignored.
2482     // Node->LRG->reg mappings are still accurate.
2483     _regalloc->Register_Allocate();
2484 
2485     // Bail out if the allocator builds too many nodes
2486     if (failing()) {
2487       return;
2488     }
2489   }
2490 
2491   // Prior to register allocation we kept empty basic blocks in case the
2492   // the allocator needed a place to spill.  After register allocation we
2493   // are not adding any new instructions.  If any basic block is empty, we
2494   // can now safely remove it.
2495   {
2496     TracePhase tp("blockOrdering", &timers[_t_blockOrdering]);
2497     cfg.remove_empty_blocks();
2498     if (do_freq_based_layout()) {
2499       PhaseBlockLayout layout(cfg);
2500     } else {
2501       cfg.set_loop_alignment();
2502     }
2503     cfg.fixup_flow();
2504   }
2505 
2506   // Apply peephole optimizations
2507   if( OptoPeephole ) {
2508     TracePhase tp("peephole", &timers[_t_peephole]);
2509     PhasePeephole peep( _regalloc, cfg);
2510     peep.do_transform();
2511   }
2512 
2513   // Do late expand if CPU requires this.
2514   if (Matcher::require_postalloc_expand) {
2515     TracePhase tp("postalloc_expand", &timers[_t_postalloc_expand]);
2516     cfg.postalloc_expand(_regalloc);
2517   }
2518 
2519   // Convert Nodes to instruction bits in a buffer
2520   {
2521     TraceTime tp("output", &timers[_t_output], CITime);
2522     Output();
2523   }
2524 
2525   print_method(PHASE_FINAL_CODE);
2526 
2527   // He's dead, Jim.
2528   _cfg     = (PhaseCFG*)((intptr_t)0xdeadbeef);
2529   _regalloc = (PhaseChaitin*)((intptr_t)0xdeadbeef);
2530 }
2531 
2532 
2533 //------------------------------dump_asm---------------------------------------
2534 // Dump formatted assembly
2535 #ifndef PRODUCT
2536 void Compile::dump_asm(int *pcs, uint pc_limit) {
2537   bool cut_short = false;
2538   tty->print_cr("#");
2539   tty->print("#  ");  _tf->dump();  tty->cr();
2540   tty->print_cr("#");
2541 
2542   // For all blocks
2543   int pc = 0x0;                 // Program counter
2544   char starts_bundle = ' ';
2545   _regalloc->dump_frame();
2546 
2547   Node *n = NULL;
2548   for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
2549     if (VMThread::should_terminate()) {
2550       cut_short = true;
2551       break;
2552     }
2553     Block* block = _cfg->get_block(i);
2554     if (block->is_connector() && !Verbose) {
2555       continue;
2556     }
2557     n = block->head();
2558     if (pcs && n->_idx < pc_limit) {
2559       tty->print("%3.3x   ", pcs[n->_idx]);
2560     } else {
2561       tty->print("      ");
2562     }
2563     block->dump_head(_cfg);
2564     if (block->is_connector()) {
2565       tty->print_cr("        # Empty connector block");
2566     } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
2567       tty->print_cr("        # Block is sole successor of call");
2568     }
2569 
2570     // For all instructions
2571     Node *delay = NULL;
2572     for (uint j = 0; j < block->number_of_nodes(); j++) {
2573       if (VMThread::should_terminate()) {
2574         cut_short = true;
2575         break;
2576       }
2577       n = block->get_node(j);
2578       if (valid_bundle_info(n)) {
2579         Bundle* bundle = node_bundling(n);
2580         if (bundle->used_in_unconditional_delay()) {
2581           delay = n;
2582           continue;
2583         }
2584         if (bundle->starts_bundle()) {
2585           starts_bundle = '+';
2586         }
2587       }
2588 
2589       if (WizardMode) {
2590         n->dump();
2591       }
2592 
2593       if( !n->is_Region() &&    // Dont print in the Assembly
2594           !n->is_Phi() &&       // a few noisely useless nodes
2595           !n->is_Proj() &&
2596           !n->is_MachTemp() &&
2597           !n->is_SafePointScalarObject() &&
2598           !n->is_Catch() &&     // Would be nice to print exception table targets
2599           !n->is_MergeMem() &&  // Not very interesting
2600           !n->is_top() &&       // Debug info table constants
2601           !(n->is_Con() && !n->is_Mach())// Debug info table constants
2602           ) {
2603         if (pcs && n->_idx < pc_limit)
2604           tty->print("%3.3x", pcs[n->_idx]);
2605         else
2606           tty->print("   ");
2607         tty->print(" %c ", starts_bundle);
2608         starts_bundle = ' ';
2609         tty->print("\t");
2610         n->format(_regalloc, tty);
2611         tty->cr();
2612       }
2613 
2614       // If we have an instruction with a delay slot, and have seen a delay,
2615       // then back up and print it
2616       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
2617         assert(delay != NULL, "no unconditional delay instruction");
2618         if (WizardMode) delay->dump();
2619 
2620         if (node_bundling(delay)->starts_bundle())
2621           starts_bundle = '+';
2622         if (pcs && n->_idx < pc_limit)
2623           tty->print("%3.3x", pcs[n->_idx]);
2624         else
2625           tty->print("   ");
2626         tty->print(" %c ", starts_bundle);
2627         starts_bundle = ' ';
2628         tty->print("\t");
2629         delay->format(_regalloc, tty);
2630         tty->cr();
2631         delay = NULL;
2632       }
2633 
2634       // Dump the exception table as well
2635       if( n->is_Catch() && (Verbose || WizardMode) ) {
2636         // Print the exception table for this offset
2637         _handler_table.print_subtable_for(pc);
2638       }
2639     }
2640 
2641     if (pcs && n->_idx < pc_limit)
2642       tty->print_cr("%3.3x", pcs[n->_idx]);
2643     else
2644       tty->cr();
2645 
2646     assert(cut_short || delay == NULL, "no unconditional delay branch");
2647 
2648   } // End of per-block dump
2649   tty->cr();
2650 
2651   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
2652 }
2653 #endif
2654 
2655 //------------------------------Final_Reshape_Counts---------------------------
2656 // This class defines counters to help identify when a method
2657 // may/must be executed using hardware with only 24-bit precision.
2658 struct Final_Reshape_Counts : public StackObj {
2659   int  _call_count;             // count non-inlined 'common' calls
2660   int  _float_count;            // count float ops requiring 24-bit precision
2661   int  _double_count;           // count double ops requiring more precision
2662   int  _java_call_count;        // count non-inlined 'java' calls
2663   int  _inner_loop_count;       // count loops which need alignment
2664   VectorSet _visited;           // Visitation flags
2665   Node_List _tests;             // Set of IfNodes & PCTableNodes
2666 
2667   Final_Reshape_Counts() :
2668     _call_count(0), _float_count(0), _double_count(0),
2669     _java_call_count(0), _inner_loop_count(0),
2670     _visited( Thread::current()->resource_area() ) { }
2671 
2672   void inc_call_count  () { _call_count  ++; }
2673   void inc_float_count () { _float_count ++; }
2674   void inc_double_count() { _double_count++; }
2675   void inc_java_call_count() { _java_call_count++; }
2676   void inc_inner_loop_count() { _inner_loop_count++; }
2677 
2678   int  get_call_count  () const { return _call_count  ; }
2679   int  get_float_count () const { return _float_count ; }
2680   int  get_double_count() const { return _double_count; }
2681   int  get_java_call_count() const { return _java_call_count; }
2682   int  get_inner_loop_count() const { return _inner_loop_count; }
2683 };
2684 
2685 #ifdef ASSERT
2686 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
2687   ciInstanceKlass *k = tp->klass()->as_instance_klass();
2688   // Make sure the offset goes inside the instance layout.
2689   return k->contains_field_offset(tp->offset());
2690   // Note that OffsetBot and OffsetTop are very negative.
2691 }
2692 #endif
2693 
2694 // Eliminate trivially redundant StoreCMs and accumulate their
2695 // precedence edges.
2696 void Compile::eliminate_redundant_card_marks(Node* n) {
2697   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
2698   if (n->in(MemNode::Address)->outcnt() > 1) {
2699     // There are multiple users of the same address so it might be
2700     // possible to eliminate some of the StoreCMs
2701     Node* mem = n->in(MemNode::Memory);
2702     Node* adr = n->in(MemNode::Address);
2703     Node* val = n->in(MemNode::ValueIn);
2704     Node* prev = n;
2705     bool done = false;
2706     // Walk the chain of StoreCMs eliminating ones that match.  As
2707     // long as it's a chain of single users then the optimization is
2708     // safe.  Eliminating partially redundant StoreCMs would require
2709     // cloning copies down the other paths.
2710     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
2711       if (adr == mem->in(MemNode::Address) &&
2712           val == mem->in(MemNode::ValueIn)) {
2713         // redundant StoreCM
2714         if (mem->req() > MemNode::OopStore) {
2715           // Hasn't been processed by this code yet.
2716           n->add_prec(mem->in(MemNode::OopStore));
2717         } else {
2718           // Already converted to precedence edge
2719           for (uint i = mem->req(); i < mem->len(); i++) {
2720             // Accumulate any precedence edges
2721             if (mem->in(i) != NULL) {
2722               n->add_prec(mem->in(i));
2723             }
2724           }
2725           // Everything above this point has been processed.
2726           done = true;
2727         }
2728         // Eliminate the previous StoreCM
2729         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
2730         assert(mem->outcnt() == 0, "should be dead");
2731         mem->disconnect_inputs(NULL, this);
2732       } else {
2733         prev = mem;
2734       }
2735       mem = prev->in(MemNode::Memory);
2736     }
2737   }
2738 }
2739 
2740 //------------------------------final_graph_reshaping_impl----------------------
2741 // Implement items 1-5 from final_graph_reshaping below.
2742 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
2743 
2744   if ( n->outcnt() == 0 ) return; // dead node
2745   uint nop = n->Opcode();
2746 
2747   // Check for 2-input instruction with "last use" on right input.
2748   // Swap to left input.  Implements item (2).
2749   if( n->req() == 3 &&          // two-input instruction
2750       n->in(1)->outcnt() > 1 && // left use is NOT a last use
2751       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
2752       n->in(2)->outcnt() == 1 &&// right use IS a last use
2753       !n->in(2)->is_Con() ) {   // right use is not a constant
2754     // Check for commutative opcode
2755     switch( nop ) {
2756     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
2757     case Op_MaxI:  case Op_MinI:
2758     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
2759     case Op_AndL:  case Op_XorL:  case Op_OrL:
2760     case Op_AndI:  case Op_XorI:  case Op_OrI: {
2761       // Move "last use" input to left by swapping inputs
2762       n->swap_edges(1, 2);
2763       break;
2764     }
2765     default:
2766       break;
2767     }
2768   }
2769 
2770 #ifdef ASSERT
2771   if( n->is_Mem() ) {
2772     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
2773     assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
2774             // oop will be recorded in oop map if load crosses safepoint
2775             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
2776                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
2777             "raw memory operations should have control edge");
2778   }
2779   if (n->is_MemBar()) {
2780     MemBarNode* mb = n->as_MemBar();
2781     if (mb->trailing_store() || mb->trailing_load_store()) {
2782       assert(mb->leading_membar()->trailing_membar() == mb, "bad membar pair");
2783       Node* mem = mb->in(MemBarNode::Precedent);
2784       assert((mb->trailing_store() && mem->is_Store() && mem->as_Store()->is_release()) ||
2785              (mb->trailing_load_store() && mem->is_LoadStore()), "missing mem op");
2786     } else if (mb->leading()) {
2787       assert(mb->trailing_membar()->leading_membar() == mb, "bad membar pair");
2788     }
2789   }
2790 #endif
2791   // Count FPU ops and common calls, implements item (3)
2792   switch( nop ) {
2793   // Count all float operations that may use FPU
2794   case Op_AddF:
2795   case Op_SubF:
2796   case Op_MulF:
2797   case Op_DivF:
2798   case Op_NegF:
2799   case Op_ModF:
2800   case Op_ConvI2F:
2801   case Op_ConF:
2802   case Op_CmpF:
2803   case Op_CmpF3:
2804   // case Op_ConvL2F: // longs are split into 32-bit halves
2805     frc.inc_float_count();
2806     break;
2807 
2808   case Op_ConvF2D:
2809   case Op_ConvD2F:
2810     frc.inc_float_count();
2811     frc.inc_double_count();
2812     break;
2813 
2814   // Count all double operations that may use FPU
2815   case Op_AddD:
2816   case Op_SubD:
2817   case Op_MulD:
2818   case Op_DivD:
2819   case Op_NegD:
2820   case Op_ModD:
2821   case Op_ConvI2D:
2822   case Op_ConvD2I:
2823   // case Op_ConvL2D: // handled by leaf call
2824   // case Op_ConvD2L: // handled by leaf call
2825   case Op_ConD:
2826   case Op_CmpD:
2827   case Op_CmpD3:
2828     frc.inc_double_count();
2829     break;
2830   case Op_Opaque1:              // Remove Opaque Nodes before matching
2831   case Op_Opaque2:              // Remove Opaque Nodes before matching
2832   case Op_Opaque3:
2833     n->subsume_by(n->in(1), this);
2834     break;
2835   case Op_CallStaticJava:
2836   case Op_CallJava:
2837   case Op_CallDynamicJava:
2838     frc.inc_java_call_count(); // Count java call site;
2839   case Op_CallRuntime:
2840   case Op_CallLeaf:
2841   case Op_CallLeafNoFP: {
2842     assert (n->is_Call(), "");
2843     CallNode *call = n->as_Call();
2844     // Count call sites where the FP mode bit would have to be flipped.
2845     // Do not count uncommon runtime calls:
2846     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
2847     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
2848     if (!call->is_CallStaticJava() || !call->as_CallStaticJava()->_name) {
2849       frc.inc_call_count();   // Count the call site
2850     } else {                  // See if uncommon argument is shared
2851       Node *n = call->in(TypeFunc::Parms);
2852       int nop = n->Opcode();
2853       // Clone shared simple arguments to uncommon calls, item (1).
2854       if (n->outcnt() > 1 &&
2855           !n->is_Proj() &&
2856           nop != Op_CreateEx &&
2857           nop != Op_CheckCastPP &&
2858           nop != Op_DecodeN &&
2859           nop != Op_DecodeNKlass &&
2860           !n->is_Mem() &&
2861           !n->is_Phi()) {
2862         Node *x = n->clone();
2863         call->set_req(TypeFunc::Parms, x);
2864       }
2865     }
2866     break;
2867   }
2868 
2869   case Op_StoreD:
2870   case Op_LoadD:
2871   case Op_LoadD_unaligned:
2872     frc.inc_double_count();
2873     goto handle_mem;
2874   case Op_StoreF:
2875   case Op_LoadF:
2876     frc.inc_float_count();
2877     goto handle_mem;
2878 
2879   case Op_StoreCM:
2880     {
2881       // Convert OopStore dependence into precedence edge
2882       Node* prec = n->in(MemNode::OopStore);
2883       n->del_req(MemNode::OopStore);
2884       n->add_prec(prec);
2885       eliminate_redundant_card_marks(n);
2886     }
2887 
2888     // fall through
2889 
2890   case Op_StoreB:
2891   case Op_StoreC:
2892   case Op_StorePConditional:
2893   case Op_StoreI:
2894   case Op_StoreL:
2895   case Op_StoreIConditional:
2896   case Op_StoreLConditional:
2897   case Op_CompareAndSwapB:
2898   case Op_CompareAndSwapS:
2899   case Op_CompareAndSwapI:
2900   case Op_CompareAndSwapL:
2901   case Op_CompareAndSwapP:
2902   case Op_CompareAndSwapN:
2903   case Op_WeakCompareAndSwapB:
2904   case Op_WeakCompareAndSwapS:
2905   case Op_WeakCompareAndSwapI:
2906   case Op_WeakCompareAndSwapL:
2907   case Op_WeakCompareAndSwapP:
2908   case Op_WeakCompareAndSwapN:
2909   case Op_CompareAndExchangeB:
2910   case Op_CompareAndExchangeS:
2911   case Op_CompareAndExchangeI:
2912   case Op_CompareAndExchangeL:
2913   case Op_CompareAndExchangeP:
2914   case Op_CompareAndExchangeN:
2915   case Op_GetAndAddS:
2916   case Op_GetAndAddB:
2917   case Op_GetAndAddI:
2918   case Op_GetAndAddL:
2919   case Op_GetAndSetS:
2920   case Op_GetAndSetB:
2921   case Op_GetAndSetI:
2922   case Op_GetAndSetL:
2923   case Op_GetAndSetP:
2924   case Op_GetAndSetN:
2925   case Op_StoreP:
2926   case Op_StoreN:
2927   case Op_StoreNKlass:
2928   case Op_LoadB:
2929   case Op_LoadUB:
2930   case Op_LoadUS:
2931   case Op_LoadI:
2932   case Op_LoadKlass:
2933   case Op_LoadNKlass:
2934   case Op_LoadL:
2935   case Op_LoadL_unaligned:
2936   case Op_LoadPLocked:
2937   case Op_LoadP:
2938 #if INCLUDE_ZGC
2939   case Op_LoadBarrierSlowReg:
2940   case Op_LoadBarrierWeakSlowReg:
2941 #endif
2942   case Op_LoadN:
2943   case Op_LoadRange:
2944   case Op_LoadS: {
2945   handle_mem:
2946 #ifdef ASSERT
2947     if( VerifyOptoOopOffsets ) {
2948       assert( n->is_Mem(), "" );
2949       MemNode *mem  = (MemNode*)n;
2950       // Check to see if address types have grounded out somehow.
2951       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
2952       assert( !tp || oop_offset_is_sane(tp), "" );
2953     }
2954 #endif
2955     break;
2956   }
2957 
2958   case Op_AddP: {               // Assert sane base pointers
2959     Node *addp = n->in(AddPNode::Address);
2960     assert( !addp->is_AddP() ||
2961             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
2962             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
2963             "Base pointers must match (addp %u)", addp->_idx );
2964 #ifdef _LP64
2965     if ((UseCompressedOops || UseCompressedClassPointers) &&
2966         addp->Opcode() == Op_ConP &&
2967         addp == n->in(AddPNode::Base) &&
2968         n->in(AddPNode::Offset)->is_Con()) {
2969       // If the transformation of ConP to ConN+DecodeN is beneficial depends
2970       // on the platform and on the compressed oops mode.
2971       // Use addressing with narrow klass to load with offset on x86.
2972       // Some platforms can use the constant pool to load ConP.
2973       // Do this transformation here since IGVN will convert ConN back to ConP.
2974       const Type* t = addp->bottom_type();
2975       bool is_oop   = t->isa_oopptr() != NULL;
2976       bool is_klass = t->isa_klassptr() != NULL;
2977 
2978       if ((is_oop   && Matcher::const_oop_prefer_decode()  ) ||
2979           (is_klass && Matcher::const_klass_prefer_decode())) {
2980         Node* nn = NULL;
2981 
2982         int op = is_oop ? Op_ConN : Op_ConNKlass;
2983 
2984         // Look for existing ConN node of the same exact type.
2985         Node* r  = root();
2986         uint cnt = r->outcnt();
2987         for (uint i = 0; i < cnt; i++) {
2988           Node* m = r->raw_out(i);
2989           if (m!= NULL && m->Opcode() == op &&
2990               m->bottom_type()->make_ptr() == t) {
2991             nn = m;
2992             break;
2993           }
2994         }
2995         if (nn != NULL) {
2996           // Decode a narrow oop to match address
2997           // [R12 + narrow_oop_reg<<3 + offset]
2998           if (is_oop) {
2999             nn = new DecodeNNode(nn, t);
3000           } else {
3001             nn = new DecodeNKlassNode(nn, t);
3002           }
3003           // Check for succeeding AddP which uses the same Base.
3004           // Otherwise we will run into the assertion above when visiting that guy.
3005           for (uint i = 0; i < n->outcnt(); ++i) {
3006             Node *out_i = n->raw_out(i);
3007             if (out_i && out_i->is_AddP() && out_i->in(AddPNode::Base) == addp) {
3008               out_i->set_req(AddPNode::Base, nn);
3009 #ifdef ASSERT
3010               for (uint j = 0; j < out_i->outcnt(); ++j) {
3011                 Node *out_j = out_i->raw_out(j);
3012                 assert(out_j == NULL || !out_j->is_AddP() || out_j->in(AddPNode::Base) != addp,
3013                        "more than 2 AddP nodes in a chain (out_j %u)", out_j->_idx);
3014               }
3015 #endif
3016             }
3017           }
3018           n->set_req(AddPNode::Base, nn);
3019           n->set_req(AddPNode::Address, nn);
3020           if (addp->outcnt() == 0) {
3021             addp->disconnect_inputs(NULL, this);
3022           }
3023         }
3024       }
3025     }
3026 #endif
3027     // platform dependent reshaping of the address expression
3028     reshape_address(n->as_AddP());
3029     break;
3030   }
3031 
3032   case Op_CastPP: {
3033     // Remove CastPP nodes to gain more freedom during scheduling but
3034     // keep the dependency they encode as control or precedence edges
3035     // (if control is set already) on memory operations. Some CastPP
3036     // nodes don't have a control (don't carry a dependency): skip
3037     // those.
3038     if (n->in(0) != NULL) {
3039       ResourceMark rm;
3040       Unique_Node_List wq;
3041       wq.push(n);
3042       for (uint next = 0; next < wq.size(); ++next) {
3043         Node *m = wq.at(next);
3044         for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
3045           Node* use = m->fast_out(i);
3046           if (use->is_Mem() || use->is_EncodeNarrowPtr()) {
3047             use->ensure_control_or_add_prec(n->in(0));
3048           } else {
3049             switch(use->Opcode()) {
3050             case Op_AddP:
3051             case Op_DecodeN:
3052             case Op_DecodeNKlass:
3053             case Op_CheckCastPP:
3054             case Op_CastPP:
3055               wq.push(use);
3056               break;
3057             }
3058           }
3059         }
3060       }
3061     }
3062     const bool is_LP64 = LP64_ONLY(true) NOT_LP64(false);
3063     if (is_LP64 && n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
3064       Node* in1 = n->in(1);
3065       const Type* t = n->bottom_type();
3066       Node* new_in1 = in1->clone();
3067       new_in1->as_DecodeN()->set_type(t);
3068 
3069       if (!Matcher::narrow_oop_use_complex_address()) {
3070         //
3071         // x86, ARM and friends can handle 2 adds in addressing mode
3072         // and Matcher can fold a DecodeN node into address by using
3073         // a narrow oop directly and do implicit NULL check in address:
3074         //
3075         // [R12 + narrow_oop_reg<<3 + offset]
3076         // NullCheck narrow_oop_reg
3077         //
3078         // On other platforms (Sparc) we have to keep new DecodeN node and
3079         // use it to do implicit NULL check in address:
3080         //
3081         // decode_not_null narrow_oop_reg, base_reg
3082         // [base_reg + offset]
3083         // NullCheck base_reg
3084         //
3085         // Pin the new DecodeN node to non-null path on these platform (Sparc)
3086         // to keep the information to which NULL check the new DecodeN node
3087         // corresponds to use it as value in implicit_null_check().
3088         //
3089         new_in1->set_req(0, n->in(0));
3090       }
3091 
3092       n->subsume_by(new_in1, this);
3093       if (in1->outcnt() == 0) {
3094         in1->disconnect_inputs(NULL, this);
3095       }
3096     } else {
3097       n->subsume_by(n->in(1), this);
3098       if (n->outcnt() == 0) {
3099         n->disconnect_inputs(NULL, this);
3100       }
3101     }
3102     break;
3103   }
3104 #ifdef _LP64
3105   case Op_CmpP:
3106     // Do this transformation here to preserve CmpPNode::sub() and
3107     // other TypePtr related Ideal optimizations (for example, ptr nullness).
3108     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
3109       Node* in1 = n->in(1);
3110       Node* in2 = n->in(2);
3111       if (!in1->is_DecodeNarrowPtr()) {
3112         in2 = in1;
3113         in1 = n->in(2);
3114       }
3115       assert(in1->is_DecodeNarrowPtr(), "sanity");
3116 
3117       Node* new_in2 = NULL;
3118       if (in2->is_DecodeNarrowPtr()) {
3119         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
3120         new_in2 = in2->in(1);
3121       } else if (in2->Opcode() == Op_ConP) {
3122         const Type* t = in2->bottom_type();
3123         if (t == TypePtr::NULL_PTR) {
3124           assert(in1->is_DecodeN(), "compare klass to null?");
3125           // Don't convert CmpP null check into CmpN if compressed
3126           // oops implicit null check is not generated.
3127           // This will allow to generate normal oop implicit null check.
3128           if (Matcher::gen_narrow_oop_implicit_null_checks())
3129             new_in2 = ConNode::make(TypeNarrowOop::NULL_PTR);
3130           //
3131           // This transformation together with CastPP transformation above
3132           // will generated code for implicit NULL checks for compressed oops.
3133           //
3134           // The original code after Optimize()
3135           //
3136           //    LoadN memory, narrow_oop_reg
3137           //    decode narrow_oop_reg, base_reg
3138           //    CmpP base_reg, NULL
3139           //    CastPP base_reg // NotNull
3140           //    Load [base_reg + offset], val_reg
3141           //
3142           // after these transformations will be
3143           //
3144           //    LoadN memory, narrow_oop_reg
3145           //    CmpN narrow_oop_reg, NULL
3146           //    decode_not_null narrow_oop_reg, base_reg
3147           //    Load [base_reg + offset], val_reg
3148           //
3149           // and the uncommon path (== NULL) will use narrow_oop_reg directly
3150           // since narrow oops can be used in debug info now (see the code in
3151           // final_graph_reshaping_walk()).
3152           //
3153           // At the end the code will be matched to
3154           // on x86:
3155           //
3156           //    Load_narrow_oop memory, narrow_oop_reg
3157           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
3158           //    NullCheck narrow_oop_reg
3159           //
3160           // and on sparc:
3161           //
3162           //    Load_narrow_oop memory, narrow_oop_reg
3163           //    decode_not_null narrow_oop_reg, base_reg
3164           //    Load [base_reg + offset], val_reg
3165           //    NullCheck base_reg
3166           //
3167         } else if (t->isa_oopptr()) {
3168           new_in2 = ConNode::make(t->make_narrowoop());
3169         } else if (t->isa_klassptr()) {
3170           new_in2 = ConNode::make(t->make_narrowklass());
3171         }
3172       }
3173       if (new_in2 != NULL) {
3174         Node* cmpN = new CmpNNode(in1->in(1), new_in2);
3175         n->subsume_by(cmpN, this);
3176         if (in1->outcnt() == 0) {
3177           in1->disconnect_inputs(NULL, this);
3178         }
3179         if (in2->outcnt() == 0) {
3180           in2->disconnect_inputs(NULL, this);
3181         }
3182       }
3183     }
3184     break;
3185 
3186   case Op_DecodeN:
3187   case Op_DecodeNKlass:
3188     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
3189     // DecodeN could be pinned when it can't be fold into
3190     // an address expression, see the code for Op_CastPP above.
3191     assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
3192     break;
3193 
3194   case Op_EncodeP:
3195   case Op_EncodePKlass: {
3196     Node* in1 = n->in(1);
3197     if (in1->is_DecodeNarrowPtr()) {
3198       n->subsume_by(in1->in(1), this);
3199     } else if (in1->Opcode() == Op_ConP) {
3200       const Type* t = in1->bottom_type();
3201       if (t == TypePtr::NULL_PTR) {
3202         assert(t->isa_oopptr(), "null klass?");
3203         n->subsume_by(ConNode::make(TypeNarrowOop::NULL_PTR), this);
3204       } else if (t->isa_oopptr()) {
3205         n->subsume_by(ConNode::make(t->make_narrowoop()), this);
3206       } else if (t->isa_klassptr()) {
3207         n->subsume_by(ConNode::make(t->make_narrowklass()), this);
3208       }
3209     }
3210     if (in1->outcnt() == 0) {
3211       in1->disconnect_inputs(NULL, this);
3212     }
3213     break;
3214   }
3215 
3216   case Op_Proj: {
3217     if (OptimizeStringConcat) {
3218       ProjNode* p = n->as_Proj();
3219       if (p->_is_io_use) {
3220         // Separate projections were used for the exception path which
3221         // are normally removed by a late inline.  If it wasn't inlined
3222         // then they will hang around and should just be replaced with
3223         // the original one.
3224         Node* proj = NULL;
3225         // Replace with just one
3226         for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
3227           Node *use = i.get();
3228           if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
3229             proj = use;
3230             break;
3231           }
3232         }
3233         assert(proj != NULL, "must be found");
3234         p->subsume_by(proj, this);
3235       }
3236     }
3237     break;
3238   }
3239 
3240   case Op_Phi:
3241     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
3242       // The EncodeP optimization may create Phi with the same edges
3243       // for all paths. It is not handled well by Register Allocator.
3244       Node* unique_in = n->in(1);
3245       assert(unique_in != NULL, "");
3246       uint cnt = n->req();
3247       for (uint i = 2; i < cnt; i++) {
3248         Node* m = n->in(i);
3249         assert(m != NULL, "");
3250         if (unique_in != m)
3251           unique_in = NULL;
3252       }
3253       if (unique_in != NULL) {
3254         n->subsume_by(unique_in, this);
3255       }
3256     }
3257     break;
3258 
3259 #endif
3260 
3261 #ifdef ASSERT
3262   case Op_CastII:
3263     // Verify that all range check dependent CastII nodes were removed.
3264     if (n->isa_CastII()->has_range_check()) {
3265       n->dump(3);
3266       assert(false, "Range check dependent CastII node was not removed");
3267     }
3268     break;
3269 #endif
3270 
3271   case Op_ModI:
3272     if (UseDivMod) {
3273       // Check if a%b and a/b both exist
3274       Node* d = n->find_similar(Op_DivI);
3275       if (d) {
3276         // Replace them with a fused divmod if supported
3277         if (Matcher::has_match_rule(Op_DivModI)) {
3278           DivModINode* divmod = DivModINode::make(n);
3279           d->subsume_by(divmod->div_proj(), this);
3280           n->subsume_by(divmod->mod_proj(), this);
3281         } else {
3282           // replace a%b with a-((a/b)*b)
3283           Node* mult = new MulINode(d, d->in(2));
3284           Node* sub  = new SubINode(d->in(1), mult);
3285           n->subsume_by(sub, this);
3286         }
3287       }
3288     }
3289     break;
3290 
3291   case Op_ModL:
3292     if (UseDivMod) {
3293       // Check if a%b and a/b both exist
3294       Node* d = n->find_similar(Op_DivL);
3295       if (d) {
3296         // Replace them with a fused divmod if supported
3297         if (Matcher::has_match_rule(Op_DivModL)) {
3298           DivModLNode* divmod = DivModLNode::make(n);
3299           d->subsume_by(divmod->div_proj(), this);
3300           n->subsume_by(divmod->mod_proj(), this);
3301         } else {
3302           // replace a%b with a-((a/b)*b)
3303           Node* mult = new MulLNode(d, d->in(2));
3304           Node* sub  = new SubLNode(d->in(1), mult);
3305           n->subsume_by(sub, this);
3306         }
3307       }
3308     }
3309     break;
3310 
3311   case Op_LoadVector:
3312   case Op_StoreVector:
3313     break;
3314 
3315   case Op_AddReductionVI:
3316   case Op_AddReductionVL:
3317   case Op_AddReductionVF:
3318   case Op_AddReductionVD:
3319   case Op_MulReductionVI:
3320   case Op_MulReductionVL:
3321   case Op_MulReductionVF:
3322   case Op_MulReductionVD:
3323     break;
3324 
3325   case Op_PackB:
3326   case Op_PackS:
3327   case Op_PackI:
3328   case Op_PackF:
3329   case Op_PackL:
3330   case Op_PackD:
3331     if (n->req()-1 > 2) {
3332       // Replace many operand PackNodes with a binary tree for matching
3333       PackNode* p = (PackNode*) n;
3334       Node* btp = p->binary_tree_pack(1, n->req());
3335       n->subsume_by(btp, this);
3336     }
3337     break;
3338   case Op_Loop:
3339   case Op_CountedLoop:
3340   case Op_OuterStripMinedLoop:
3341     if (n->as_Loop()->is_inner_loop()) {
3342       frc.inc_inner_loop_count();
3343     }
3344     n->as_Loop()->verify_strip_mined(0);
3345     break;
3346   case Op_LShiftI:
3347   case Op_RShiftI:
3348   case Op_URShiftI:
3349   case Op_LShiftL:
3350   case Op_RShiftL:
3351   case Op_URShiftL:
3352     if (Matcher::need_masked_shift_count) {
3353       // The cpu's shift instructions don't restrict the count to the
3354       // lower 5/6 bits. We need to do the masking ourselves.
3355       Node* in2 = n->in(2);
3356       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
3357       const TypeInt* t = in2->find_int_type();
3358       if (t != NULL && t->is_con()) {
3359         juint shift = t->get_con();
3360         if (shift > mask) { // Unsigned cmp
3361           n->set_req(2, ConNode::make(TypeInt::make(shift & mask)));
3362         }
3363       } else {
3364         if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
3365           Node* shift = new AndINode(in2, ConNode::make(TypeInt::make(mask)));
3366           n->set_req(2, shift);
3367         }
3368       }
3369       if (in2->outcnt() == 0) { // Remove dead node
3370         in2->disconnect_inputs(NULL, this);
3371       }
3372     }
3373     break;
3374   case Op_MemBarStoreStore:
3375   case Op_MemBarRelease:
3376     // Break the link with AllocateNode: it is no longer useful and
3377     // confuses register allocation.
3378     if (n->req() > MemBarNode::Precedent) {
3379       n->set_req(MemBarNode::Precedent, top());
3380     }
3381     break;
3382   case Op_MemBarAcquire: {
3383     if (n->as_MemBar()->trailing_load() && n->req() > MemBarNode::Precedent) {
3384       // At parse time, the trailing MemBarAcquire for a volatile load
3385       // is created with an edge to the load. After optimizations,
3386       // that input may be a chain of Phis. If those phis have no
3387       // other use, then the MemBarAcquire keeps them alive and
3388       // register allocation can be confused.
3389       ResourceMark rm;
3390       Unique_Node_List wq;
3391       wq.push(n->in(MemBarNode::Precedent));
3392       n->set_req(MemBarNode::Precedent, top());
3393       while (wq.size() > 0) {
3394         Node* m = wq.pop();
3395         if (m->outcnt() == 0) {
3396           for (uint j = 0; j < m->req(); j++) {
3397             Node* in = m->in(j);
3398             if (in != NULL) {
3399               wq.push(in);
3400             }
3401           }
3402           m->disconnect_inputs(NULL, this);
3403         }
3404       }
3405     }
3406     break;
3407   }
3408   case Op_RangeCheck: {
3409     RangeCheckNode* rc = n->as_RangeCheck();
3410     Node* iff = new IfNode(rc->in(0), rc->in(1), rc->_prob, rc->_fcnt);
3411     n->subsume_by(iff, this);
3412     frc._tests.push(iff);
3413     break;
3414   }
3415   case Op_ConvI2L: {
3416     if (!Matcher::convi2l_type_required) {
3417       // Code generation on some platforms doesn't need accurate
3418       // ConvI2L types. Widening the type can help remove redundant
3419       // address computations.
3420       n->as_Type()->set_type(TypeLong::INT);
3421       ResourceMark rm;
3422       Node_List wq;
3423       wq.push(n);
3424       for (uint next = 0; next < wq.size(); next++) {
3425         Node *m = wq.at(next);
3426 
3427         for(;;) {
3428           // Loop over all nodes with identical inputs edges as m
3429           Node* k = m->find_similar(m->Opcode());
3430           if (k == NULL) {
3431             break;
3432           }
3433           // Push their uses so we get a chance to remove node made
3434           // redundant
3435           for (DUIterator_Fast imax, i = k->fast_outs(imax); i < imax; i++) {
3436             Node* u = k->fast_out(i);
3437             assert(!wq.contains(u), "shouldn't process one node several times");
3438             if (u->Opcode() == Op_LShiftL ||
3439                 u->Opcode() == Op_AddL ||
3440                 u->Opcode() == Op_SubL ||
3441                 u->Opcode() == Op_AddP) {
3442               wq.push(u);
3443             }
3444           }
3445           // Replace all nodes with identical edges as m with m
3446           k->subsume_by(m, this);
3447         }
3448       }
3449     }
3450     break;
3451   }
3452   case Op_CmpUL: {
3453     if (!Matcher::has_match_rule(Op_CmpUL)) {
3454       // We don't support unsigned long comparisons. Set 'max_idx_expr'
3455       // to max_julong if < 0 to make the signed comparison fail.
3456       ConINode* sign_pos = new ConINode(TypeInt::make(BitsPerLong - 1));
3457       Node* sign_bit_mask = new RShiftLNode(n->in(1), sign_pos);
3458       Node* orl = new OrLNode(n->in(1), sign_bit_mask);
3459       ConLNode* remove_sign_mask = new ConLNode(TypeLong::make(max_jlong));
3460       Node* andl = new AndLNode(orl, remove_sign_mask);
3461       Node* cmp = new CmpLNode(andl, n->in(2));
3462       n->subsume_by(cmp, this);
3463     }
3464     break;
3465   }
3466   default:
3467     assert( !n->is_Call(), "" );
3468     assert( !n->is_Mem(), "" );
3469     assert( nop != Op_ProfileBoolean, "should be eliminated during IGVN");
3470     break;
3471   }
3472 
3473   // Collect CFG split points
3474   if (n->is_MultiBranch() && !n->is_RangeCheck()) {
3475     frc._tests.push(n);
3476   }
3477 }
3478 
3479 //------------------------------final_graph_reshaping_walk---------------------
3480 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
3481 // requires that the walk visits a node's inputs before visiting the node.
3482 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
3483   ResourceArea *area = Thread::current()->resource_area();
3484   Unique_Node_List sfpt(area);
3485 
3486   frc._visited.set(root->_idx); // first, mark node as visited
3487   uint cnt = root->req();
3488   Node *n = root;
3489   uint  i = 0;
3490   while (true) {
3491     if (i < cnt) {
3492       // Place all non-visited non-null inputs onto stack
3493       Node* m = n->in(i);
3494       ++i;
3495       if (m != NULL && !frc._visited.test_set(m->_idx)) {
3496         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL) {
3497           // compute worst case interpreter size in case of a deoptimization
3498           update_interpreter_frame_size(m->as_SafePoint()->jvms()->interpreter_frame_size());
3499 
3500           sfpt.push(m);
3501         }
3502         cnt = m->req();
3503         nstack.push(n, i); // put on stack parent and next input's index
3504         n = m;
3505         i = 0;
3506       }
3507     } else {
3508       // Now do post-visit work
3509       final_graph_reshaping_impl( n, frc );
3510       if (nstack.is_empty())
3511         break;             // finished
3512       n = nstack.node();   // Get node from stack
3513       cnt = n->req();
3514       i = nstack.index();
3515       nstack.pop();        // Shift to the next node on stack
3516     }
3517   }
3518 
3519   // Skip next transformation if compressed oops are not used.
3520   if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
3521       (!UseCompressedOops && !UseCompressedClassPointers))
3522     return;
3523 
3524   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
3525   // It could be done for an uncommon traps or any safepoints/calls
3526   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
3527   while (sfpt.size() > 0) {
3528     n = sfpt.pop();
3529     JVMState *jvms = n->as_SafePoint()->jvms();
3530     assert(jvms != NULL, "sanity");
3531     int start = jvms->debug_start();
3532     int end   = n->req();
3533     bool is_uncommon = (n->is_CallStaticJava() &&
3534                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
3535     for (int j = start; j < end; j++) {
3536       Node* in = n->in(j);
3537       if (in->is_DecodeNarrowPtr()) {
3538         bool safe_to_skip = true;
3539         if (!is_uncommon ) {
3540           // Is it safe to skip?
3541           for (uint i = 0; i < in->outcnt(); i++) {
3542             Node* u = in->raw_out(i);
3543             if (!u->is_SafePoint() ||
3544                 (u->is_Call() && u->as_Call()->has_non_debug_use(n))) {
3545               safe_to_skip = false;
3546             }
3547           }
3548         }
3549         if (safe_to_skip) {
3550           n->set_req(j, in->in(1));
3551         }
3552         if (in->outcnt() == 0) {
3553           in->disconnect_inputs(NULL, this);
3554         }
3555       }
3556     }
3557   }
3558 }
3559 
3560 //------------------------------final_graph_reshaping--------------------------
3561 // Final Graph Reshaping.
3562 //
3563 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
3564 //     and not commoned up and forced early.  Must come after regular
3565 //     optimizations to avoid GVN undoing the cloning.  Clone constant
3566 //     inputs to Loop Phis; these will be split by the allocator anyways.
3567 //     Remove Opaque nodes.
3568 // (2) Move last-uses by commutative operations to the left input to encourage
3569 //     Intel update-in-place two-address operations and better register usage
3570 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
3571 //     calls canonicalizing them back.
3572 // (3) Count the number of double-precision FP ops, single-precision FP ops
3573 //     and call sites.  On Intel, we can get correct rounding either by
3574 //     forcing singles to memory (requires extra stores and loads after each
3575 //     FP bytecode) or we can set a rounding mode bit (requires setting and
3576 //     clearing the mode bit around call sites).  The mode bit is only used
3577 //     if the relative frequency of single FP ops to calls is low enough.
3578 //     This is a key transform for SPEC mpeg_audio.
3579 // (4) Detect infinite loops; blobs of code reachable from above but not
3580 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
3581 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
3582 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
3583 //     Detection is by looking for IfNodes where only 1 projection is
3584 //     reachable from below or CatchNodes missing some targets.
3585 // (5) Assert for insane oop offsets in debug mode.
3586 
3587 bool Compile::final_graph_reshaping() {
3588   // an infinite loop may have been eliminated by the optimizer,
3589   // in which case the graph will be empty.
3590   if (root()->req() == 1) {
3591     record_method_not_compilable("trivial infinite loop");
3592     return true;
3593   }
3594 
3595   // Expensive nodes have their control input set to prevent the GVN
3596   // from freely commoning them. There's no GVN beyond this point so
3597   // no need to keep the control input. We want the expensive nodes to
3598   // be freely moved to the least frequent code path by gcm.
3599   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
3600   for (int i = 0; i < expensive_count(); i++) {
3601     _expensive_nodes->at(i)->set_req(0, NULL);
3602   }
3603 
3604   Final_Reshape_Counts frc;
3605 
3606   // Visit everybody reachable!
3607   // Allocate stack of size C->live_nodes()/2 to avoid frequent realloc
3608   Node_Stack nstack(live_nodes() >> 1);
3609   final_graph_reshaping_walk(nstack, root(), frc);
3610 
3611   // Check for unreachable (from below) code (i.e., infinite loops).
3612   for( uint i = 0; i < frc._tests.size(); i++ ) {
3613     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
3614     // Get number of CFG targets.
3615     // Note that PCTables include exception targets after calls.
3616     uint required_outcnt = n->required_outcnt();
3617     if (n->outcnt() != required_outcnt) {
3618       // Check for a few special cases.  Rethrow Nodes never take the
3619       // 'fall-thru' path, so expected kids is 1 less.
3620       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
3621         if (n->in(0)->in(0)->is_Call()) {
3622           CallNode *call = n->in(0)->in(0)->as_Call();
3623           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
3624             required_outcnt--;      // Rethrow always has 1 less kid
3625           } else if (call->req() > TypeFunc::Parms &&
3626                      call->is_CallDynamicJava()) {
3627             // Check for null receiver. In such case, the optimizer has
3628             // detected that the virtual call will always result in a null
3629             // pointer exception. The fall-through projection of this CatchNode
3630             // will not be populated.
3631             Node *arg0 = call->in(TypeFunc::Parms);
3632             if (arg0->is_Type() &&
3633                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
3634               required_outcnt--;
3635             }
3636           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
3637                      call->req() > TypeFunc::Parms+1 &&
3638                      call->is_CallStaticJava()) {
3639             // Check for negative array length. In such case, the optimizer has
3640             // detected that the allocation attempt will always result in an
3641             // exception. There is no fall-through projection of this CatchNode .
3642             Node *arg1 = call->in(TypeFunc::Parms+1);
3643             if (arg1->is_Type() &&
3644                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
3645               required_outcnt--;
3646             }
3647           }
3648         }
3649       }
3650       // Recheck with a better notion of 'required_outcnt'
3651       if (n->outcnt() != required_outcnt) {
3652         record_method_not_compilable("malformed control flow");
3653         return true;            // Not all targets reachable!
3654       }
3655     }
3656     // Check that I actually visited all kids.  Unreached kids
3657     // must be infinite loops.
3658     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
3659       if (!frc._visited.test(n->fast_out(j)->_idx)) {
3660         record_method_not_compilable("infinite loop");
3661         return true;            // Found unvisited kid; must be unreach
3662       }
3663 
3664     // Here so verification code in final_graph_reshaping_walk()
3665     // always see an OuterStripMinedLoopEnd
3666     if (n->is_OuterStripMinedLoopEnd()) {
3667       IfNode* init_iff = n->as_If();
3668       Node* iff = new IfNode(init_iff->in(0), init_iff->in(1), init_iff->_prob, init_iff->_fcnt);
3669       n->subsume_by(iff, this);
3670     }
3671   }
3672 
3673   // If original bytecodes contained a mixture of floats and doubles
3674   // check if the optimizer has made it homogenous, item (3).
3675   if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
3676       frc.get_float_count() > 32 &&
3677       frc.get_double_count() == 0 &&
3678       (10 * frc.get_call_count() < frc.get_float_count()) ) {
3679     set_24_bit_selection_and_mode( false,  true );
3680   }
3681 
3682   set_java_calls(frc.get_java_call_count());
3683   set_inner_loops(frc.get_inner_loop_count());
3684 
3685   // No infinite loops, no reason to bail out.
3686   return false;
3687 }
3688 
3689 //-----------------------------too_many_traps----------------------------------
3690 // Report if there are too many traps at the current method and bci.
3691 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
3692 bool Compile::too_many_traps(ciMethod* method,
3693                              int bci,
3694                              Deoptimization::DeoptReason reason) {
3695   ciMethodData* md = method->method_data();
3696   if (md->is_empty()) {
3697     // Assume the trap has not occurred, or that it occurred only
3698     // because of a transient condition during start-up in the interpreter.
3699     return false;
3700   }
3701   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3702   if (md->has_trap_at(bci, m, reason) != 0) {
3703     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
3704     // Also, if there are multiple reasons, or if there is no per-BCI record,
3705     // assume the worst.
3706     if (log())
3707       log()->elem("observe trap='%s' count='%d'",
3708                   Deoptimization::trap_reason_name(reason),
3709                   md->trap_count(reason));
3710     return true;
3711   } else {
3712     // Ignore method/bci and see if there have been too many globally.
3713     return too_many_traps(reason, md);
3714   }
3715 }
3716 
3717 // Less-accurate variant which does not require a method and bci.
3718 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
3719                              ciMethodData* logmd) {
3720   if (trap_count(reason) >= Deoptimization::per_method_trap_limit(reason)) {
3721     // Too many traps globally.
3722     // Note that we use cumulative trap_count, not just md->trap_count.
3723     if (log()) {
3724       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
3725       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
3726                   Deoptimization::trap_reason_name(reason),
3727                   mcount, trap_count(reason));
3728     }
3729     return true;
3730   } else {
3731     // The coast is clear.
3732     return false;
3733   }
3734 }
3735 
3736 //--------------------------too_many_recompiles--------------------------------
3737 // Report if there are too many recompiles at the current method and bci.
3738 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
3739 // Is not eager to return true, since this will cause the compiler to use
3740 // Action_none for a trap point, to avoid too many recompilations.
3741 bool Compile::too_many_recompiles(ciMethod* method,
3742                                   int bci,
3743                                   Deoptimization::DeoptReason reason) {
3744   ciMethodData* md = method->method_data();
3745   if (md->is_empty()) {
3746     // Assume the trap has not occurred, or that it occurred only
3747     // because of a transient condition during start-up in the interpreter.
3748     return false;
3749   }
3750   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
3751   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
3752   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
3753   Deoptimization::DeoptReason per_bc_reason
3754     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
3755   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
3756   if ((per_bc_reason == Deoptimization::Reason_none
3757        || md->has_trap_at(bci, m, reason) != 0)
3758       // The trap frequency measure we care about is the recompile count:
3759       && md->trap_recompiled_at(bci, m)
3760       && md->overflow_recompile_count() >= bc_cutoff) {
3761     // Do not emit a trap here if it has already caused recompilations.
3762     // Also, if there are multiple reasons, or if there is no per-BCI record,
3763     // assume the worst.
3764     if (log())
3765       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
3766                   Deoptimization::trap_reason_name(reason),
3767                   md->trap_count(reason),
3768                   md->overflow_recompile_count());
3769     return true;
3770   } else if (trap_count(reason) != 0
3771              && decompile_count() >= m_cutoff) {
3772     // Too many recompiles globally, and we have seen this sort of trap.
3773     // Use cumulative decompile_count, not just md->decompile_count.
3774     if (log())
3775       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
3776                   Deoptimization::trap_reason_name(reason),
3777                   md->trap_count(reason), trap_count(reason),
3778                   md->decompile_count(), decompile_count());
3779     return true;
3780   } else {
3781     // The coast is clear.
3782     return false;
3783   }
3784 }
3785 
3786 // Compute when not to trap. Used by matching trap based nodes and
3787 // NullCheck optimization.
3788 void Compile::set_allowed_deopt_reasons() {
3789   _allowed_reasons = 0;
3790   if (is_method_compilation()) {
3791     for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
3792       assert(rs < BitsPerInt, "recode bit map");
3793       if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
3794         _allowed_reasons |= nth_bit(rs);
3795       }
3796     }
3797   }
3798 }
3799 
3800 #ifndef PRODUCT
3801 //------------------------------verify_graph_edges---------------------------
3802 // Walk the Graph and verify that there is a one-to-one correspondence
3803 // between Use-Def edges and Def-Use edges in the graph.
3804 void Compile::verify_graph_edges(bool no_dead_code) {
3805   if (VerifyGraphEdges) {
3806     ResourceArea *area = Thread::current()->resource_area();
3807     Unique_Node_List visited(area);
3808     // Call recursive graph walk to check edges
3809     _root->verify_edges(visited);
3810     if (no_dead_code) {
3811       // Now make sure that no visited node is used by an unvisited node.
3812       bool dead_nodes = false;
3813       Unique_Node_List checked(area);
3814       while (visited.size() > 0) {
3815         Node* n = visited.pop();
3816         checked.push(n);
3817         for (uint i = 0; i < n->outcnt(); i++) {
3818           Node* use = n->raw_out(i);
3819           if (checked.member(use))  continue;  // already checked
3820           if (visited.member(use))  continue;  // already in the graph
3821           if (use->is_Con())        continue;  // a dead ConNode is OK
3822           // At this point, we have found a dead node which is DU-reachable.
3823           if (!dead_nodes) {
3824             tty->print_cr("*** Dead nodes reachable via DU edges:");
3825             dead_nodes = true;
3826           }
3827           use->dump(2);
3828           tty->print_cr("---");
3829           checked.push(use);  // No repeats; pretend it is now checked.
3830         }
3831       }
3832       assert(!dead_nodes, "using nodes must be reachable from root");
3833     }
3834   }
3835 }
3836 
3837 // Verify GC barriers consistency
3838 // Currently supported:
3839 // - G1 pre-barriers (see GraphKit::g1_write_barrier_pre())
3840 void Compile::verify_barriers() {
3841 #if INCLUDE_G1GC
3842   if (UseG1GC) {
3843     // Verify G1 pre-barriers
3844     const int marking_offset = in_bytes(G1ThreadLocalData::satb_mark_queue_active_offset());
3845 
3846     ResourceArea *area = Thread::current()->resource_area();
3847     Unique_Node_List visited(area);
3848     Node_List worklist(area);
3849     // We're going to walk control flow backwards starting from the Root
3850     worklist.push(_root);
3851     while (worklist.size() > 0) {
3852       Node* x = worklist.pop();
3853       if (x == NULL || x == top()) continue;
3854       if (visited.member(x)) {
3855         continue;
3856       } else {
3857         visited.push(x);
3858       }
3859 
3860       if (x->is_Region()) {
3861         for (uint i = 1; i < x->req(); i++) {
3862           worklist.push(x->in(i));
3863         }
3864       } else {
3865         worklist.push(x->in(0));
3866         // We are looking for the pattern:
3867         //                            /->ThreadLocal
3868         // If->Bool->CmpI->LoadB->AddP->ConL(marking_offset)
3869         //              \->ConI(0)
3870         // We want to verify that the If and the LoadB have the same control
3871         // See GraphKit::g1_write_barrier_pre()
3872         if (x->is_If()) {
3873           IfNode *iff = x->as_If();
3874           if (iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) {
3875             CmpNode *cmp = iff->in(1)->in(1)->as_Cmp();
3876             if (cmp->Opcode() == Op_CmpI && cmp->in(2)->is_Con() && cmp->in(2)->bottom_type()->is_int()->get_con() == 0
3877                 && cmp->in(1)->is_Load()) {
3878               LoadNode* load = cmp->in(1)->as_Load();
3879               if (load->Opcode() == Op_LoadB && load->in(2)->is_AddP() && load->in(2)->in(2)->Opcode() == Op_ThreadLocal
3880                   && load->in(2)->in(3)->is_Con()
3881                   && load->in(2)->in(3)->bottom_type()->is_intptr_t()->get_con() == marking_offset) {
3882 
3883                 Node* if_ctrl = iff->in(0);
3884                 Node* load_ctrl = load->in(0);
3885 
3886                 if (if_ctrl != load_ctrl) {
3887                   // Skip possible CProj->NeverBranch in infinite loops
3888                   if ((if_ctrl->is_Proj() && if_ctrl->Opcode() == Op_CProj)
3889                       && (if_ctrl->in(0)->is_MultiBranch() && if_ctrl->in(0)->Opcode() == Op_NeverBranch)) {
3890                     if_ctrl = if_ctrl->in(0)->in(0);
3891                   }
3892                 }
3893                 assert(load_ctrl != NULL && if_ctrl == load_ctrl, "controls must match");
3894               }
3895             }
3896           }
3897         }
3898       }
3899     }
3900   }
3901 #endif
3902 }
3903 
3904 #endif
3905 
3906 // The Compile object keeps track of failure reasons separately from the ciEnv.
3907 // This is required because there is not quite a 1-1 relation between the
3908 // ciEnv and its compilation task and the Compile object.  Note that one
3909 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
3910 // to backtrack and retry without subsuming loads.  Other than this backtracking
3911 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
3912 // by the logic in C2Compiler.
3913 void Compile::record_failure(const char* reason) {
3914   if (log() != NULL) {
3915     log()->elem("failure reason='%s' phase='compile'", reason);
3916   }
3917   if (_failure_reason == NULL) {
3918     // Record the first failure reason.
3919     _failure_reason = reason;
3920   }
3921 
3922   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
3923     C->print_method(PHASE_FAILURE);
3924   }
3925   _root = NULL;  // flush the graph, too
3926 }
3927 
3928 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator)
3929   : TraceTime(name, accumulator, CITime, CITimeVerbose),
3930     _phase_name(name), _dolog(CITimeVerbose)
3931 {
3932   if (_dolog) {
3933     C = Compile::current();
3934     _log = C->log();
3935   } else {
3936     C = NULL;
3937     _log = NULL;
3938   }
3939   if (_log != NULL) {
3940     _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3941     _log->stamp();
3942     _log->end_head();
3943   }
3944 }
3945 
3946 Compile::TracePhase::~TracePhase() {
3947 
3948   C = Compile::current();
3949   if (_dolog) {
3950     _log = C->log();
3951   } else {
3952     _log = NULL;
3953   }
3954 
3955 #ifdef ASSERT
3956   if (PrintIdealNodeCount) {
3957     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
3958                   _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
3959   }
3960 
3961   if (VerifyIdealNodeCount) {
3962     Compile::current()->print_missing_nodes();
3963   }
3964 #endif
3965 
3966   if (_log != NULL) {
3967     _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
3968   }
3969 }
3970 
3971 //=============================================================================
3972 // Two Constant's are equal when the type and the value are equal.
3973 bool Compile::Constant::operator==(const Constant& other) {
3974   if (type()          != other.type()         )  return false;
3975   if (can_be_reused() != other.can_be_reused())  return false;
3976   // For floating point values we compare the bit pattern.
3977   switch (type()) {
3978   case T_INT:
3979   case T_FLOAT:   return (_v._value.i == other._v._value.i);
3980   case T_LONG:
3981   case T_DOUBLE:  return (_v._value.j == other._v._value.j);
3982   case T_OBJECT:
3983   case T_ADDRESS: return (_v._value.l == other._v._value.l);
3984   case T_VOID:    return (_v._value.l == other._v._value.l);  // jump-table entries
3985   case T_METADATA: return (_v._metadata == other._v._metadata);
3986   default: ShouldNotReachHere(); return false;
3987   }
3988 }
3989 
3990 static int type_to_size_in_bytes(BasicType t) {
3991   switch (t) {
3992   case T_INT:     return sizeof(jint   );
3993   case T_LONG:    return sizeof(jlong  );
3994   case T_FLOAT:   return sizeof(jfloat );
3995   case T_DOUBLE:  return sizeof(jdouble);
3996   case T_METADATA: return sizeof(Metadata*);
3997     // We use T_VOID as marker for jump-table entries (labels) which
3998     // need an internal word relocation.
3999   case T_VOID:
4000   case T_ADDRESS:
4001   case T_OBJECT:  return sizeof(jobject);
4002   default:
4003     ShouldNotReachHere();
4004     return -1;
4005   }
4006 }
4007 
4008 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
4009   // sort descending
4010   if (a->freq() > b->freq())  return -1;
4011   if (a->freq() < b->freq())  return  1;
4012   return 0;
4013 }
4014 
4015 void Compile::ConstantTable::calculate_offsets_and_size() {
4016   // First, sort the array by frequencies.
4017   _constants.sort(qsort_comparator);
4018 
4019 #ifdef ASSERT
4020   // Make sure all jump-table entries were sorted to the end of the
4021   // array (they have a negative frequency).
4022   bool found_void = false;
4023   for (int i = 0; i < _constants.length(); i++) {
4024     Constant con = _constants.at(i);
4025     if (con.type() == T_VOID)
4026       found_void = true;  // jump-tables
4027     else
4028       assert(!found_void, "wrong sorting");
4029   }
4030 #endif
4031 
4032   int offset = 0;
4033   for (int i = 0; i < _constants.length(); i++) {
4034     Constant* con = _constants.adr_at(i);
4035 
4036     // Align offset for type.
4037     int typesize = type_to_size_in_bytes(con->type());
4038     offset = align_up(offset, typesize);
4039     con->set_offset(offset);   // set constant's offset
4040 
4041     if (con->type() == T_VOID) {
4042       MachConstantNode* n = (MachConstantNode*) con->get_jobject();
4043       offset = offset + typesize * n->outcnt();  // expand jump-table
4044     } else {
4045       offset = offset + typesize;
4046     }
4047   }
4048 
4049   // Align size up to the next section start (which is insts; see
4050   // CodeBuffer::align_at_start).
4051   assert(_size == -1, "already set?");
4052   _size = align_up(offset, (int)CodeEntryAlignment);
4053 }
4054 
4055 void Compile::ConstantTable::emit(CodeBuffer& cb) {
4056   MacroAssembler _masm(&cb);
4057   for (int i = 0; i < _constants.length(); i++) {
4058     Constant con = _constants.at(i);
4059     address constant_addr = NULL;
4060     switch (con.type()) {
4061     case T_INT:    constant_addr = _masm.int_constant(   con.get_jint()   ); break;
4062     case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
4063     case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
4064     case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
4065     case T_OBJECT: {
4066       jobject obj = con.get_jobject();
4067       int oop_index = _masm.oop_recorder()->find_index(obj);
4068       constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
4069       break;
4070     }
4071     case T_ADDRESS: {
4072       address addr = (address) con.get_jobject();
4073       constant_addr = _masm.address_constant(addr);
4074       break;
4075     }
4076     // We use T_VOID as marker for jump-table entries (labels) which
4077     // need an internal word relocation.
4078     case T_VOID: {
4079       MachConstantNode* n = (MachConstantNode*) con.get_jobject();
4080       // Fill the jump-table with a dummy word.  The real value is
4081       // filled in later in fill_jump_table.
4082       address dummy = (address) n;
4083       constant_addr = _masm.address_constant(dummy);
4084       // Expand jump-table
4085       for (uint i = 1; i < n->outcnt(); i++) {
4086         address temp_addr = _masm.address_constant(dummy + i);
4087         assert(temp_addr, "consts section too small");
4088       }
4089       break;
4090     }
4091     case T_METADATA: {
4092       Metadata* obj = con.get_metadata();
4093       int metadata_index = _masm.oop_recorder()->find_index(obj);
4094       constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
4095       break;
4096     }
4097     default: ShouldNotReachHere();
4098     }
4099     assert(constant_addr, "consts section too small");
4100     assert((constant_addr - _masm.code()->consts()->start()) == con.offset(),
4101             "must be: %d == %d", (int) (constant_addr - _masm.code()->consts()->start()), (int)(con.offset()));
4102   }
4103 }
4104 
4105 int Compile::ConstantTable::find_offset(Constant& con) const {
4106   int idx = _constants.find(con);
4107   guarantee(idx != -1, "constant must be in constant table");
4108   int offset = _constants.at(idx).offset();
4109   guarantee(offset != -1, "constant table not emitted yet?");
4110   return offset;
4111 }
4112 
4113 void Compile::ConstantTable::add(Constant& con) {
4114   if (con.can_be_reused()) {
4115     int idx = _constants.find(con);
4116     if (idx != -1 && _constants.at(idx).can_be_reused()) {
4117       _constants.adr_at(idx)->inc_freq(con.freq());  // increase the frequency by the current value
4118       return;
4119     }
4120   }
4121   (void) _constants.append(con);
4122 }
4123 
4124 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
4125   Block* b = Compile::current()->cfg()->get_block_for_node(n);
4126   Constant con(type, value, b->_freq);
4127   add(con);
4128   return con;
4129 }
4130 
4131 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
4132   Constant con(metadata);
4133   add(con);
4134   return con;
4135 }
4136 
4137 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
4138   jvalue value;
4139   BasicType type = oper->type()->basic_type();
4140   switch (type) {
4141   case T_LONG:    value.j = oper->constantL(); break;
4142   case T_FLOAT:   value.f = oper->constantF(); break;
4143   case T_DOUBLE:  value.d = oper->constantD(); break;
4144   case T_OBJECT:
4145   case T_ADDRESS: value.l = (jobject) oper->constant(); break;
4146   case T_METADATA: return add((Metadata*)oper->constant()); break;
4147   default: guarantee(false, "unhandled type: %s", type2name(type));
4148   }
4149   return add(n, type, value);
4150 }
4151 
4152 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
4153   jvalue value;
4154   // We can use the node pointer here to identify the right jump-table
4155   // as this method is called from Compile::Fill_buffer right before
4156   // the MachNodes are emitted and the jump-table is filled (means the
4157   // MachNode pointers do not change anymore).
4158   value.l = (jobject) n;
4159   Constant con(T_VOID, value, next_jump_table_freq(), false);  // Labels of a jump-table cannot be reused.
4160   add(con);
4161   return con;
4162 }
4163 
4164 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
4165   // If called from Compile::scratch_emit_size do nothing.
4166   if (Compile::current()->in_scratch_emit_size())  return;
4167 
4168   assert(labels.is_nonempty(), "must be");
4169   assert((uint) labels.length() == n->outcnt(), "must be equal: %d == %d", labels.length(), n->outcnt());
4170 
4171   // Since MachConstantNode::constant_offset() also contains
4172   // table_base_offset() we need to subtract the table_base_offset()
4173   // to get the plain offset into the constant table.
4174   int offset = n->constant_offset() - table_base_offset();
4175 
4176   MacroAssembler _masm(&cb);
4177   address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
4178 
4179   for (uint i = 0; i < n->outcnt(); i++) {
4180     address* constant_addr = &jump_table_base[i];
4181     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));
4182     *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
4183     cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
4184   }
4185 }
4186 
4187 //----------------------------static_subtype_check-----------------------------
4188 // Shortcut important common cases when superklass is exact:
4189 // (0) superklass is java.lang.Object (can occur in reflective code)
4190 // (1) subklass is already limited to a subtype of superklass => always ok
4191 // (2) subklass does not overlap with superklass => always fail
4192 // (3) superklass has NO subtypes and we can check with a simple compare.
4193 int Compile::static_subtype_check(ciKlass* superk, ciKlass* subk) {
4194   if (StressReflectiveCode) {
4195     return SSC_full_test;       // Let caller generate the general case.
4196   }
4197 
4198   if (superk == env()->Object_klass()) {
4199     return SSC_always_true;     // (0) this test cannot fail
4200   }
4201 
4202   ciType* superelem = superk;
4203   if (superelem->is_array_klass())
4204     superelem = superelem->as_array_klass()->base_element_type();
4205 
4206   if (!subk->is_interface()) {  // cannot trust static interface types yet
4207     if (subk->is_subtype_of(superk)) {
4208       return SSC_always_true;   // (1) false path dead; no dynamic test needed
4209     }
4210     if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
4211         !superk->is_subtype_of(subk)) {
4212       return SSC_always_false;
4213     }
4214   }
4215 
4216   // If casting to an instance klass, it must have no subtypes
4217   if (superk->is_interface()) {
4218     // Cannot trust interfaces yet.
4219     // %%% S.B. superk->nof_implementors() == 1
4220   } else if (superelem->is_instance_klass()) {
4221     ciInstanceKlass* ik = superelem->as_instance_klass();
4222     if (!ik->has_subklass() && !ik->is_interface()) {
4223       if (!ik->is_final()) {
4224         // Add a dependency if there is a chance of a later subclass.
4225         dependencies()->assert_leaf_type(ik);
4226       }
4227       return SSC_easy_test;     // (3) caller can do a simple ptr comparison
4228     }
4229   } else {
4230     // A primitive array type has no subtypes.
4231     return SSC_easy_test;       // (3) caller can do a simple ptr comparison
4232   }
4233 
4234   return SSC_full_test;
4235 }
4236 
4237 Node* Compile::conv_I2X_index(PhaseGVN* phase, Node* idx, const TypeInt* sizetype, Node* ctrl) {
4238 #ifdef _LP64
4239   // The scaled index operand to AddP must be a clean 64-bit value.
4240   // Java allows a 32-bit int to be incremented to a negative
4241   // value, which appears in a 64-bit register as a large
4242   // positive number.  Using that large positive number as an
4243   // operand in pointer arithmetic has bad consequences.
4244   // On the other hand, 32-bit overflow is rare, and the possibility
4245   // can often be excluded, if we annotate the ConvI2L node with
4246   // a type assertion that its value is known to be a small positive
4247   // number.  (The prior range check has ensured this.)
4248   // This assertion is used by ConvI2LNode::Ideal.
4249   int index_max = max_jint - 1;  // array size is max_jint, index is one less
4250   if (sizetype != NULL) index_max = sizetype->_hi - 1;
4251   const TypeInt* iidxtype = TypeInt::make(0, index_max, Type::WidenMax);
4252   idx = constrained_convI2L(phase, idx, iidxtype, ctrl);
4253 #endif
4254   return idx;
4255 }
4256 
4257 // Convert integer value to a narrowed long type dependent on ctrl (for example, a range check)
4258 Node* Compile::constrained_convI2L(PhaseGVN* phase, Node* value, const TypeInt* itype, Node* ctrl) {
4259   if (ctrl != NULL) {
4260     // Express control dependency by a CastII node with a narrow type.
4261     value = new CastIINode(value, itype, false, true /* range check dependency */);
4262     // Make the CastII node dependent on the control input to prevent the narrowed ConvI2L
4263     // node from floating above the range check during loop optimizations. Otherwise, the
4264     // ConvI2L node may be eliminated independently of the range check, causing the data path
4265     // to become TOP while the control path is still there (although it's unreachable).
4266     value->set_req(0, ctrl);
4267     // Save CastII node to remove it after loop optimizations.
4268     phase->C->add_range_check_cast(value);
4269     value = phase->transform(value);
4270   }
4271   const TypeLong* ltype = TypeLong::make(itype->_lo, itype->_hi, itype->_widen);
4272   return phase->transform(new ConvI2LNode(value, ltype));
4273 }
4274 
4275 // The message about the current inlining is accumulated in
4276 // _print_inlining_stream and transfered into the _print_inlining_list
4277 // once we know whether inlining succeeds or not. For regular
4278 // inlining, messages are appended to the buffer pointed by
4279 // _print_inlining_idx in the _print_inlining_list. For late inlining,
4280 // a new buffer is added after _print_inlining_idx in the list. This
4281 // way we can update the inlining message for late inlining call site
4282 // when the inlining is attempted again.
4283 void Compile::print_inlining_init() {
4284   if (print_inlining() || print_intrinsics()) {
4285     _print_inlining_stream = new stringStream();
4286     _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
4287   }
4288 }
4289 
4290 void Compile::print_inlining_reinit() {
4291   if (print_inlining() || print_intrinsics()) {
4292     // Re allocate buffer when we change ResourceMark
4293     _print_inlining_stream = new stringStream();
4294   }
4295 }
4296 
4297 void Compile::print_inlining_reset() {
4298   _print_inlining_stream->reset();
4299 }
4300 
4301 void Compile::print_inlining_commit() {
4302   assert(print_inlining() || print_intrinsics(), "PrintInlining off?");
4303   // Transfer the message from _print_inlining_stream to the current
4304   // _print_inlining_list buffer and clear _print_inlining_stream.
4305   _print_inlining_list->at(_print_inlining_idx).ss()->write(_print_inlining_stream->as_string(), _print_inlining_stream->size());
4306   print_inlining_reset();
4307 }
4308 
4309 void Compile::print_inlining_push() {
4310   // Add new buffer to the _print_inlining_list at current position
4311   _print_inlining_idx++;
4312   _print_inlining_list->insert_before(_print_inlining_idx, PrintInliningBuffer());
4313 }
4314 
4315 Compile::PrintInliningBuffer& Compile::print_inlining_current() {
4316   return _print_inlining_list->at(_print_inlining_idx);
4317 }
4318 
4319 void Compile::print_inlining_update(CallGenerator* cg) {
4320   if (print_inlining() || print_intrinsics()) {
4321     if (!cg->is_late_inline()) {
4322       if (print_inlining_current().cg() != NULL) {
4323         print_inlining_push();
4324       }
4325       print_inlining_commit();
4326     } else {
4327       if (print_inlining_current().cg() != cg &&
4328           (print_inlining_current().cg() != NULL ||
4329            print_inlining_current().ss()->size() != 0)) {
4330         print_inlining_push();
4331       }
4332       print_inlining_commit();
4333       print_inlining_current().set_cg(cg);
4334     }
4335   }
4336 }
4337 
4338 void Compile::print_inlining_move_to(CallGenerator* cg) {
4339   // We resume inlining at a late inlining call site. Locate the
4340   // corresponding inlining buffer so that we can update it.
4341   if (print_inlining()) {
4342     for (int i = 0; i < _print_inlining_list->length(); i++) {
4343       if (_print_inlining_list->adr_at(i)->cg() == cg) {
4344         _print_inlining_idx = i;
4345         return;
4346       }
4347     }
4348     ShouldNotReachHere();
4349   }
4350 }
4351 
4352 void Compile::print_inlining_update_delayed(CallGenerator* cg) {
4353   if (print_inlining()) {
4354     assert(_print_inlining_stream->size() > 0, "missing inlining msg");
4355     assert(print_inlining_current().cg() == cg, "wrong entry");
4356     // replace message with new message
4357     _print_inlining_list->at_put(_print_inlining_idx, PrintInliningBuffer());
4358     print_inlining_commit();
4359     print_inlining_current().set_cg(cg);
4360   }
4361 }
4362 
4363 void Compile::print_inlining_assert_ready() {
4364   assert(!_print_inlining || _print_inlining_stream->size() == 0, "loosing data");
4365 }
4366 
4367 void Compile::process_print_inlining() {
4368   bool do_print_inlining = print_inlining() || print_intrinsics();
4369   if (do_print_inlining || log() != NULL) {
4370     // Print inlining message for candidates that we couldn't inline
4371     // for lack of space
4372     for (int i = 0; i < _late_inlines.length(); i++) {
4373       CallGenerator* cg = _late_inlines.at(i);
4374       if (!cg->is_mh_late_inline()) {
4375         const char* msg = "live nodes > LiveNodeCountInliningCutoff";
4376         if (do_print_inlining) {
4377           cg->print_inlining_late(msg);
4378         }
4379         log_late_inline_failure(cg, msg);
4380       }
4381     }
4382   }
4383   if (do_print_inlining) {
4384     ResourceMark rm;
4385     stringStream ss;
4386     for (int i = 0; i < _print_inlining_list->length(); i++) {
4387       ss.print("%s", _print_inlining_list->adr_at(i)->ss()->as_string());
4388     }
4389     size_t end = ss.size();
4390     _print_inlining_output = NEW_ARENA_ARRAY(comp_arena(), char, end+1);
4391     strncpy(_print_inlining_output, ss.base(), end+1);
4392     _print_inlining_output[end] = 0;
4393   }
4394 }
4395 
4396 void Compile::dump_print_inlining() {
4397   if (_print_inlining_output != NULL) {
4398     tty->print_raw(_print_inlining_output);
4399   }
4400 }
4401 
4402 void Compile::log_late_inline(CallGenerator* cg) {
4403   if (log() != NULL) {
4404     log()->head("late_inline method='%d'  inline_id='" JLONG_FORMAT "'", log()->identify(cg->method()),
4405                 cg->unique_id());
4406     JVMState* p = cg->call_node()->jvms();
4407     while (p != NULL) {
4408       log()->elem("jvms bci='%d' method='%d'", p->bci(), log()->identify(p->method()));
4409       p = p->caller();
4410     }
4411     log()->tail("late_inline");
4412   }
4413 }
4414 
4415 void Compile::log_late_inline_failure(CallGenerator* cg, const char* msg) {
4416   log_late_inline(cg);
4417   if (log() != NULL) {
4418     log()->inline_fail(msg);
4419   }
4420 }
4421 
4422 void Compile::log_inline_id(CallGenerator* cg) {
4423   if (log() != NULL) {
4424     // The LogCompilation tool needs a unique way to identify late
4425     // inline call sites. This id must be unique for this call site in
4426     // this compilation. Try to have it unique across compilations as
4427     // well because it can be convenient when grepping through the log
4428     // file.
4429     // Distinguish OSR compilations from others in case CICountOSR is
4430     // on.
4431     jlong id = ((jlong)unique()) + (((jlong)compile_id()) << 33) + (CICountOSR && is_osr_compilation() ? ((jlong)1) << 32 : 0);
4432     cg->set_unique_id(id);
4433     log()->elem("inline_id id='" JLONG_FORMAT "'", id);
4434   }
4435 }
4436 
4437 void Compile::log_inline_failure(const char* msg) {
4438   if (C->log() != NULL) {
4439     C->log()->inline_fail(msg);
4440   }
4441 }
4442 
4443 
4444 // Dump inlining replay data to the stream.
4445 // Don't change thread state and acquire any locks.
4446 void Compile::dump_inline_data(outputStream* out) {
4447   InlineTree* inl_tree = ilt();
4448   if (inl_tree != NULL) {
4449     out->print(" inline %d", inl_tree->count());
4450     inl_tree->dump_replay_data(out);
4451   }
4452 }
4453 
4454 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
4455   if (n1->Opcode() < n2->Opcode())      return -1;
4456   else if (n1->Opcode() > n2->Opcode()) return 1;
4457 
4458   assert(n1->req() == n2->req(), "can't compare %s nodes: n1->req() = %d, n2->req() = %d", NodeClassNames[n1->Opcode()], n1->req(), n2->req());
4459   for (uint i = 1; i < n1->req(); i++) {
4460     if (n1->in(i) < n2->in(i))      return -1;
4461     else if (n1->in(i) > n2->in(i)) return 1;
4462   }
4463 
4464   return 0;
4465 }
4466 
4467 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
4468   Node* n1 = *n1p;
4469   Node* n2 = *n2p;
4470 
4471   return cmp_expensive_nodes(n1, n2);
4472 }
4473 
4474 void Compile::sort_expensive_nodes() {
4475   if (!expensive_nodes_sorted()) {
4476     _expensive_nodes->sort(cmp_expensive_nodes);
4477   }
4478 }
4479 
4480 bool Compile::expensive_nodes_sorted() const {
4481   for (int i = 1; i < _expensive_nodes->length(); i++) {
4482     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
4483       return false;
4484     }
4485   }
4486   return true;
4487 }
4488 
4489 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
4490   if (_expensive_nodes->length() == 0) {
4491     return false;
4492   }
4493 
4494   assert(OptimizeExpensiveOps, "optimization off?");
4495 
4496   // Take this opportunity to remove dead nodes from the list
4497   int j = 0;
4498   for (int i = 0; i < _expensive_nodes->length(); i++) {
4499     Node* n = _expensive_nodes->at(i);
4500     if (!n->is_unreachable(igvn)) {
4501       assert(n->is_expensive(), "should be expensive");
4502       _expensive_nodes->at_put(j, n);
4503       j++;
4504     }
4505   }
4506   _expensive_nodes->trunc_to(j);
4507 
4508   // Then sort the list so that similar nodes are next to each other
4509   // and check for at least two nodes of identical kind with same data
4510   // inputs.
4511   sort_expensive_nodes();
4512 
4513   for (int i = 0; i < _expensive_nodes->length()-1; i++) {
4514     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
4515       return true;
4516     }
4517   }
4518 
4519   return false;
4520 }
4521 
4522 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
4523   if (_expensive_nodes->length() == 0) {
4524     return;
4525   }
4526 
4527   assert(OptimizeExpensiveOps, "optimization off?");
4528 
4529   // Sort to bring similar nodes next to each other and clear the
4530   // control input of nodes for which there's only a single copy.
4531   sort_expensive_nodes();
4532 
4533   int j = 0;
4534   int identical = 0;
4535   int i = 0;
4536   bool modified = false;
4537   for (; i < _expensive_nodes->length()-1; i++) {
4538     assert(j <= i, "can't write beyond current index");
4539     if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
4540       identical++;
4541       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4542       continue;
4543     }
4544     if (identical > 0) {
4545       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4546       identical = 0;
4547     } else {
4548       Node* n = _expensive_nodes->at(i);
4549       igvn.replace_input_of(n, 0, NULL);
4550       igvn.hash_insert(n);
4551       modified = true;
4552     }
4553   }
4554   if (identical > 0) {
4555     _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
4556   } else if (_expensive_nodes->length() >= 1) {
4557     Node* n = _expensive_nodes->at(i);
4558     igvn.replace_input_of(n, 0, NULL);
4559     igvn.hash_insert(n);
4560     modified = true;
4561   }
4562   _expensive_nodes->trunc_to(j);
4563   if (modified) {
4564     igvn.optimize();
4565   }
4566 }
4567 
4568 void Compile::add_expensive_node(Node * n) {
4569   assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
4570   assert(n->is_expensive(), "expensive nodes with non-null control here only");
4571   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
4572   if (OptimizeExpensiveOps) {
4573     _expensive_nodes->append(n);
4574   } else {
4575     // Clear control input and let IGVN optimize expensive nodes if
4576     // OptimizeExpensiveOps is off.
4577     n->set_req(0, NULL);
4578   }
4579 }
4580 
4581 /**
4582  * Remove the speculative part of types and clean up the graph
4583  */
4584 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
4585   if (UseTypeSpeculation) {
4586     Unique_Node_List worklist;
4587     worklist.push(root());
4588     int modified = 0;
4589     // Go over all type nodes that carry a speculative type, drop the
4590     // speculative part of the type and enqueue the node for an igvn
4591     // which may optimize it out.
4592     for (uint next = 0; next < worklist.size(); ++next) {
4593       Node *n  = worklist.at(next);
4594       if (n->is_Type()) {
4595         TypeNode* tn = n->as_Type();
4596         const Type* t = tn->type();
4597         const Type* t_no_spec = t->remove_speculative();
4598         if (t_no_spec != t) {
4599           bool in_hash = igvn.hash_delete(n);
4600           assert(in_hash, "node should be in igvn hash table");
4601           tn->set_type(t_no_spec);
4602           igvn.hash_insert(n);
4603           igvn._worklist.push(n); // give it a chance to go away
4604           modified++;
4605         }
4606       }
4607       uint max = n->len();
4608       for( uint i = 0; i < max; ++i ) {
4609         Node *m = n->in(i);
4610         if (not_a_node(m))  continue;
4611         worklist.push(m);
4612       }
4613     }
4614     // Drop the speculative part of all types in the igvn's type table
4615     igvn.remove_speculative_types();
4616     if (modified > 0) {
4617       igvn.optimize();
4618     }
4619 #ifdef ASSERT
4620     // Verify that after the IGVN is over no speculative type has resurfaced
4621     worklist.clear();
4622     worklist.push(root());
4623     for (uint next = 0; next < worklist.size(); ++next) {
4624       Node *n  = worklist.at(next);
4625       const Type* t = igvn.type_or_null(n);
4626       assert((t == NULL) || (t == t->remove_speculative()), "no more speculative types");
4627       if (n->is_Type()) {
4628         t = n->as_Type()->type();
4629         assert(t == t->remove_speculative(), "no more speculative types");
4630       }
4631       uint max = n->len();
4632       for( uint i = 0; i < max; ++i ) {
4633         Node *m = n->in(i);
4634         if (not_a_node(m))  continue;
4635         worklist.push(m);
4636       }
4637     }
4638     igvn.check_no_speculative_types();
4639 #endif
4640   }
4641 }
4642 
4643 // Auxiliary method to support randomized stressing/fuzzing.
4644 //
4645 // This method can be called the arbitrary number of times, with current count
4646 // as the argument. The logic allows selecting a single candidate from the
4647 // running list of candidates as follows:
4648 //    int count = 0;
4649 //    Cand* selected = null;
4650 //    while(cand = cand->next()) {
4651 //      if (randomized_select(++count)) {
4652 //        selected = cand;
4653 //      }
4654 //    }
4655 //
4656 // Including count equalizes the chances any candidate is "selected".
4657 // This is useful when we don't have the complete list of candidates to choose
4658 // from uniformly. In this case, we need to adjust the randomicity of the
4659 // selection, or else we will end up biasing the selection towards the latter
4660 // candidates.
4661 //
4662 // Quick back-envelope calculation shows that for the list of n candidates
4663 // the equal probability for the candidate to persist as "best" can be
4664 // achieved by replacing it with "next" k-th candidate with the probability
4665 // of 1/k. It can be easily shown that by the end of the run, the
4666 // probability for any candidate is converged to 1/n, thus giving the
4667 // uniform distribution among all the candidates.
4668 //
4669 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
4670 #define RANDOMIZED_DOMAIN_POW 29
4671 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
4672 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
4673 bool Compile::randomized_select(int count) {
4674   assert(count > 0, "only positive");
4675   return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);
4676 }
4677 
4678 CloneMap&     Compile::clone_map()                 { return _clone_map; }
4679 void          Compile::set_clone_map(Dict* d)      { _clone_map._dict = d; }
4680 
4681 void NodeCloneInfo::dump() const {
4682   tty->print(" {%d:%d} ", idx(), gen());
4683 }
4684 
4685 void CloneMap::clone(Node* old, Node* nnn, int gen) {
4686   uint64_t val = value(old->_idx);
4687   NodeCloneInfo cio(val);
4688   assert(val != 0, "old node should be in the map");
4689   NodeCloneInfo cin(cio.idx(), gen + cio.gen());
4690   insert(nnn->_idx, cin.get());
4691 #ifndef PRODUCT
4692   if (is_debug()) {
4693     tty->print_cr("CloneMap::clone inserted node %d info {%d:%d} into CloneMap", nnn->_idx, cin.idx(), cin.gen());
4694   }
4695 #endif
4696 }
4697 
4698 void CloneMap::verify_insert_and_clone(Node* old, Node* nnn, int gen) {
4699   NodeCloneInfo cio(value(old->_idx));
4700   if (cio.get() == 0) {
4701     cio.set(old->_idx, 0);
4702     insert(old->_idx, cio.get());
4703 #ifndef PRODUCT
4704     if (is_debug()) {
4705       tty->print_cr("CloneMap::verify_insert_and_clone inserted node %d info {%d:%d} into CloneMap", old->_idx, cio.idx(), cio.gen());
4706     }
4707 #endif
4708   }
4709   clone(old, nnn, gen);
4710 }
4711 
4712 int CloneMap::max_gen() const {
4713   int g = 0;
4714   DictI di(_dict);
4715   for(; di.test(); ++di) {
4716     int t = gen(di._key);
4717     if (g < t) {
4718       g = t;
4719 #ifndef PRODUCT
4720       if (is_debug()) {
4721         tty->print_cr("CloneMap::max_gen() update max=%d from %d", g, _2_node_idx_t(di._key));
4722       }
4723 #endif
4724     }
4725   }
4726   return g;
4727 }
4728 
4729 void CloneMap::dump(node_idx_t key) const {
4730   uint64_t val = value(key);
4731   if (val != 0) {
4732     NodeCloneInfo ni(val);
4733     ni.dump();
4734   }
4735 }