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_ZGC
  80 #include "gc/z/c2/zBarrierSetC2.hpp"
  81 #endif
  82 
  83 
  84 // -------------------- Compile::mach_constant_base_node -----------------------
  85 // Constant table base node singleton.
  86 MachConstantBaseNode* Compile::mach_constant_base_node() {
  87   if (_mach_constant_base_node == NULL) {
  88     _mach_constant_base_node = new MachConstantBaseNode();
  89     _mach_constant_base_node->add_req(C->root());
  90   }
  91   return _mach_constant_base_node;
  92 }
  93 
  94 
  95 /// Support for intrinsics.
  96 
  97 // Return the index at which m must be inserted (or already exists).
  98 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
  99 class IntrinsicDescPair {
 100  private:
 101   ciMethod* _m;
 102   bool _is_virtual;
 103  public:
 104   IntrinsicDescPair(ciMethod* m, bool is_virtual) : _m(m), _is_virtual(is_virtual) {}
 105   static int compare(IntrinsicDescPair* const& key, CallGenerator* const& elt) {
 106     ciMethod* m= elt->method();
 107     ciMethod* key_m = key->_m;
 108     if (key_m < m)      return -1;
 109     else if (key_m > m) return 1;
 110     else {
 111       bool is_virtual = elt->is_virtual();
 112       bool key_virtual = key->_is_virtual;
 113       if (key_virtual < is_virtual)      return -1;
 114       else if (key_virtual > is_virtual) return 1;
 115       else                               return 0;
 116     }
 117   }
 118 };
 119 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual, bool& found) {
 120 #ifdef ASSERT
 121   for (int i = 1; i < _intrinsics->length(); i++) {
 122     CallGenerator* cg1 = _intrinsics->at(i-1);
 123     CallGenerator* cg2 = _intrinsics->at(i);
 124     assert(cg1->method() != cg2->method()
 125            ? cg1->method()     < cg2->method()
 126            : cg1->is_virtual() < cg2->is_virtual(),
 127            "compiler intrinsics list must stay sorted");
 128   }
 129 #endif
 130   IntrinsicDescPair pair(m, is_virtual);
 131   return _intrinsics->find_sorted<IntrinsicDescPair*, IntrinsicDescPair::compare>(&pair, found);
 132 }
 133 
 134 void Compile::register_intrinsic(CallGenerator* cg) {
 135   if (_intrinsics == NULL) {
 136     _intrinsics = new (comp_arena())GrowableArray<CallGenerator*>(comp_arena(), 60, 0, NULL);
 137   }
 138   int len = _intrinsics->length();
 139   bool found = false;
 140   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual(), found);
 141   assert(!found, "registering twice");
 142   _intrinsics->insert_before(index, cg);
 143   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
 144 }
 145 
 146 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
 147   assert(m->is_loaded(), "don't try this on unloaded methods");
 148   if (_intrinsics != NULL) {
 149     bool found = false;
 150     int index = intrinsic_insertion_index(m, is_virtual, found);
 151      if (found) {
 152       return _intrinsics->at(index);
 153     }
 154   }
 155   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
 156   if (m->intrinsic_id() != vmIntrinsics::_none &&
 157       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
 158     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
 159     if (cg != NULL) {
 160       // Save it for next time:
 161       register_intrinsic(cg);
 162       return cg;
 163     } else {
 164       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
 165     }
 166   }
 167   return NULL;
 168 }
 169 
 170 // Compile:: register_library_intrinsics and make_vm_intrinsic are defined
 171 // in library_call.cpp.
 172 
 173 
 174 #ifndef PRODUCT
 175 // statistics gathering...
 176 
 177 juint  Compile::_intrinsic_hist_count[vmIntrinsics::ID_LIMIT] = {0};
 178 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::ID_LIMIT] = {0};
 179 
 180 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
 181   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
 182   int oflags = _intrinsic_hist_flags[id];
 183   assert(flags != 0, "what happened?");
 184   if (is_virtual) {
 185     flags |= _intrinsic_virtual;
 186   }
 187   bool changed = (flags != oflags);
 188   if ((flags & _intrinsic_worked) != 0) {
 189     juint count = (_intrinsic_hist_count[id] += 1);
 190     if (count == 1) {
 191       changed = true;           // first time
 192     }
 193     // increment the overall count also:
 194     _intrinsic_hist_count[vmIntrinsics::_none] += 1;
 195   }
 196   if (changed) {
 197     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
 198       // Something changed about the intrinsic's virtuality.
 199       if ((flags & _intrinsic_virtual) != 0) {
 200         // This is the first use of this intrinsic as a virtual call.
 201         if (oflags != 0) {
 202           // We already saw it as a non-virtual, so note both cases.
 203           flags |= _intrinsic_both;
 204         }
 205       } else if ((oflags & _intrinsic_both) == 0) {
 206         // This is the first use of this intrinsic as a non-virtual
 207         flags |= _intrinsic_both;
 208       }
 209     }
 210     _intrinsic_hist_flags[id] = (jubyte) (oflags | flags);
 211   }
 212   // update the overall flags also:
 213   _intrinsic_hist_flags[vmIntrinsics::_none] |= (jubyte) flags;
 214   return changed;
 215 }
 216 
 217 static char* format_flags(int flags, char* buf) {
 218   buf[0] = 0;
 219   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
 220   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
 221   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
 222   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
 223   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
 224   if (buf[0] == 0)  strcat(buf, ",");
 225   assert(buf[0] == ',', "must be");
 226   return &buf[1];
 227 }
 228 
 229 void Compile::print_intrinsic_statistics() {
 230   char flagsbuf[100];
 231   ttyLocker ttyl;
 232   if (xtty != NULL)  xtty->head("statistics type='intrinsic'");
 233   tty->print_cr("Compiler intrinsic usage:");
 234   juint total = _intrinsic_hist_count[vmIntrinsics::_none];
 235   if (total == 0)  total = 1;  // avoid div0 in case of no successes
 236   #define PRINT_STAT_LINE(name, c, f) \
 237     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
 238   for (int index = 1 + (int)vmIntrinsics::_none; index < (int)vmIntrinsics::ID_LIMIT; index++) {
 239     vmIntrinsics::ID id = (vmIntrinsics::ID) index;
 240     int   flags = _intrinsic_hist_flags[id];
 241     juint count = _intrinsic_hist_count[id];
 242     if ((flags | count) != 0) {
 243       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
 244     }
 245   }
 246   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[vmIntrinsics::_none], flagsbuf));
 247   if (xtty != NULL)  xtty->tail("statistics");
 248 }
 249 
 250 void Compile::print_statistics() {
 251   { ttyLocker ttyl;
 252     if (xtty != NULL)  xtty->head("statistics type='opto'");
 253     Parse::print_statistics();
 254     PhaseCCP::print_statistics();
 255     PhaseRegAlloc::print_statistics();
 256     Scheduling::print_statistics();
 257     PhasePeephole::print_statistics();
 258     PhaseIdealLoop::print_statistics();
 259     if (xtty != NULL)  xtty->tail("statistics");
 260   }
 261   if (_intrinsic_hist_flags[vmIntrinsics::_none] != 0) {
 262     // put this under its own <statistics> element.
 263     print_intrinsic_statistics();
 264   }
 265 }
 266 #endif //PRODUCT
 267 
 268 // Support for bundling info
 269 Bundle* Compile::node_bundling(const Node *n) {
 270   assert(valid_bundle_info(n), "oob");
 271   return &_node_bundling_base[n->_idx];
 272 }
 273 
 274 bool Compile::valid_bundle_info(const Node *n) {
 275   return (_node_bundling_limit > n->_idx);
 276 }
 277 
 278 
 279 void Compile::gvn_replace_by(Node* n, Node* nn) {
 280   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
 281     Node* use = n->last_out(i);
 282     bool is_in_table = initial_gvn()->hash_delete(use);
 283     uint uses_found = 0;
 284     for (uint j = 0; j < use->len(); j++) {
 285       if (use->in(j) == n) {
 286         if (j < use->req())
 287           use->set_req(j, nn);
 288         else
 289           use->set_prec(j, nn);
 290         uses_found++;
 291       }
 292     }
 293     if (is_in_table) {
 294       // reinsert into table
 295       initial_gvn()->hash_find_insert(use);
 296     }
 297     record_for_igvn(use);
 298     i -= uses_found;    // we deleted 1 or more copies of this edge
 299   }
 300 }
 301 
 302 
 303 static inline bool not_a_node(const Node* n) {
 304   if (n == NULL)                   return true;
 305   if (((intptr_t)n & 1) != 0)      return true;  // uninitialized, etc.
 306   if (*(address*)n == badAddress)  return true;  // kill by Node::destruct
 307   return false;
 308 }
 309 
 310 // Identify all nodes that are reachable from below, useful.
 311 // Use breadth-first pass that records state in a Unique_Node_List,
 312 // recursive traversal is slower.
 313 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
 314   int estimated_worklist_size = live_nodes();
 315   useful.map( estimated_worklist_size, NULL );  // preallocate space
 316 
 317   // Initialize worklist
 318   if (root() != NULL)     { useful.push(root()); }
 319   // If 'top' is cached, declare it useful to preserve cached node
 320   if( cached_top_node() ) { useful.push(cached_top_node()); }
 321 
 322   // Push all useful nodes onto the list, breadthfirst
 323   for( uint next = 0; next < useful.size(); ++next ) {
 324     assert( next < unique(), "Unique useful nodes < total nodes");
 325     Node *n  = useful.at(next);
 326     uint max = n->len();
 327     for( uint i = 0; i < max; ++i ) {
 328       Node *m = n->in(i);
 329       if (not_a_node(m))  continue;
 330       useful.push(m);
 331     }
 332   }
 333 }
 334 
 335 // Update dead_node_list with any missing dead nodes using useful
 336 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
 337 void Compile::update_dead_node_list(Unique_Node_List &useful) {
 338   uint max_idx = unique();
 339   VectorSet& useful_node_set = useful.member_set();
 340 
 341   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
 342     // If node with index node_idx is not in useful set,
 343     // mark it as dead in dead node list.
 344     if (! useful_node_set.test(node_idx) ) {
 345       record_dead_node(node_idx);
 346     }
 347   }
 348 }
 349 
 350 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
 351   int shift = 0;
 352   for (int i = 0; i < inlines->length(); i++) {
 353     CallGenerator* cg = inlines->at(i);
 354     CallNode* call = cg->call_node();
 355     if (shift > 0) {
 356       inlines->at_put(i-shift, cg);
 357     }
 358     if (!useful.member(call)) {
 359       shift++;
 360     }
 361   }
 362   inlines->trunc_to(inlines->length()-shift);
 363 }
 364 
 365 // Disconnect all useless nodes by disconnecting those at the boundary.
 366 void Compile::remove_useless_nodes(Unique_Node_List &useful) {
 367   uint next = 0;
 368   while (next < useful.size()) {
 369     Node *n = useful.at(next++);
 370     if (n->is_SafePoint()) {
 371       // We're done with a parsing phase. Replaced nodes are not valid
 372       // beyond that point.
 373       n->as_SafePoint()->delete_replaced_nodes();
 374     }
 375     // Use raw traversal of out edges since this code removes out edges
 376     int max = n->outcnt();
 377     for (int j = 0; j < max; ++j) {
 378       Node* child = n->raw_out(j);
 379       if (! useful.member(child)) {
 380         assert(!child->is_top() || child != top(),
 381                "If top is cached in Compile object it is in useful list");
 382         // Only need to remove this out-edge to the useless node
 383         n->raw_del_out(j);
 384         --j;
 385         --max;
 386       }
 387     }
 388     if (n->outcnt() == 1 && n->has_special_unique_user()) {
 389       record_for_igvn(n->unique_out());
 390     }
 391   }
 392   // Remove useless macro and predicate opaq nodes
 393   for (int i = C->macro_count()-1; i >= 0; i--) {
 394     Node* n = C->macro_node(i);
 395     if (!useful.member(n)) {
 396       remove_macro_node(n);
 397     }
 398   }
 399   // Remove useless CastII nodes with range check dependency
 400   for (int i = range_check_cast_count() - 1; i >= 0; i--) {
 401     Node* cast = range_check_cast_node(i);
 402     if (!useful.member(cast)) {
 403       remove_range_check_cast(cast);
 404     }
 405   }
 406   // Remove useless expensive nodes
 407   for (int i = C->expensive_count()-1; i >= 0; i--) {
 408     Node* n = C->expensive_node(i);
 409     if (!useful.member(n)) {
 410       remove_expensive_node(n);
 411     }
 412   }
 413   // Remove useless Opaque4 nodes
 414   for (int i = opaque4_count() - 1; i >= 0; i--) {
 415     Node* opaq = opaque4_node(i);
 416     if (!useful.member(opaq)) {
 417       remove_opaque4_node(opaq);
 418     }
 419   }
 420   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 421   bs->eliminate_useless_gc_barriers(useful, this);
 422   // clean up the late inline lists
 423   remove_useless_late_inlines(&_string_late_inlines, useful);
 424   remove_useless_late_inlines(&_boxing_late_inlines, useful);
 425   remove_useless_late_inlines(&_late_inlines, useful);
 426   remove_useless_late_inlines(&_vector_reboxing_late_inlines, useful);
 427   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
 428 }
 429 
 430 //------------------------------frame_size_in_words-----------------------------
 431 // frame_slots in units of words
 432 int Compile::frame_size_in_words() const {
 433   // shift is 0 in LP32 and 1 in LP64
 434   const int shift = (LogBytesPerWord - LogBytesPerInt);
 435   int words = _frame_slots >> shift;
 436   assert( words << shift == _frame_slots, "frame size must be properly aligned in LP64" );
 437   return words;
 438 }
 439 
 440 // To bang the stack of this compiled method we use the stack size
 441 // that the interpreter would need in case of a deoptimization. This
 442 // removes the need to bang the stack in the deoptimization blob which
 443 // in turn simplifies stack overflow handling.
 444 int Compile::bang_size_in_bytes() const {
 445   return MAX2(frame_size_in_bytes() + os::extra_bang_size_in_bytes(), _interpreter_frame_size);
 446 }
 447 
 448 // ============================================================================
 449 //------------------------------CompileWrapper---------------------------------
 450 class CompileWrapper : public StackObj {
 451   Compile *const _compile;
 452  public:
 453   CompileWrapper(Compile* compile);
 454 
 455   ~CompileWrapper();
 456 };
 457 
 458 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
 459   // the Compile* pointer is stored in the current ciEnv:
 460   ciEnv* env = compile->env();
 461   assert(env == ciEnv::current(), "must already be a ciEnv active");
 462   assert(env->compiler_data() == NULL, "compile already active?");
 463   env->set_compiler_data(compile);
 464   assert(compile == Compile::current(), "sanity");
 465 
 466   compile->set_type_dict(NULL);
 467   compile->set_clone_map(new Dict(cmpkey, hashkey, _compile->comp_arena()));
 468   compile->clone_map().set_clone_idx(0);
 469   compile->set_type_hwm(NULL);
 470   compile->set_type_last_size(0);
 471   compile->set_last_tf(NULL, NULL);
 472   compile->set_indexSet_arena(NULL);
 473   compile->set_indexSet_free_block_list(NULL);
 474   compile->init_type_arena();
 475   Type::Initialize(compile);
 476   _compile->set_scratch_buffer_blob(NULL);
 477   _compile->begin_method();
 478   _compile->clone_map().set_debug(_compile->has_method() && _compile->directive()->CloneMapDebugOption);
 479 }
 480 CompileWrapper::~CompileWrapper() {
 481   _compile->end_method();
 482   if (_compile->scratch_buffer_blob() != NULL)
 483     BufferBlob::free(_compile->scratch_buffer_blob());
 484   _compile->env()->set_compiler_data(NULL);
 485 }
 486 
 487 
 488 //----------------------------print_compile_messages---------------------------
 489 void Compile::print_compile_messages() {
 490 #ifndef PRODUCT
 491   // Check if recompiling
 492   if (_subsume_loads == false && PrintOpto) {
 493     // Recompiling without allowing machine instructions to subsume loads
 494     tty->print_cr("*********************************************************");
 495     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
 496     tty->print_cr("*********************************************************");
 497   }
 498   if (_do_escape_analysis != DoEscapeAnalysis && PrintOpto) {
 499     // Recompiling without escape analysis
 500     tty->print_cr("*********************************************************");
 501     tty->print_cr("** Bailout: Recompile without escape analysis          **");
 502     tty->print_cr("*********************************************************");
 503   }
 504   if (_eliminate_boxing != EliminateAutoBox && PrintOpto) {
 505     // Recompiling without boxing elimination
 506     tty->print_cr("*********************************************************");
 507     tty->print_cr("** Bailout: Recompile without boxing elimination       **");
 508     tty->print_cr("*********************************************************");
 509   }
 510   if (C->directive()->BreakAtCompileOption) {
 511     // Open the debugger when compiling this method.
 512     tty->print("### Breaking when compiling: ");
 513     method()->print_short_name();
 514     tty->cr();
 515     BREAKPOINT;
 516   }
 517 
 518   if( PrintOpto ) {
 519     if (is_osr_compilation()) {
 520       tty->print("[OSR]%3d", _compile_id);
 521     } else {
 522       tty->print("%3d", _compile_id);
 523     }
 524   }
 525 #endif
 526 }
 527 
 528 
 529 //-----------------------init_scratch_buffer_blob------------------------------
 530 // Construct a temporary BufferBlob and cache it for this compile.
 531 void Compile::init_scratch_buffer_blob(int const_size) {
 532   // If there is already a scratch buffer blob allocated and the
 533   // constant section is big enough, use it.  Otherwise free the
 534   // current and allocate a new one.
 535   BufferBlob* blob = scratch_buffer_blob();
 536   if ((blob != NULL) && (const_size <= _scratch_const_size)) {
 537     // Use the current blob.
 538   } else {
 539     if (blob != NULL) {
 540       BufferBlob::free(blob);
 541     }
 542 
 543     ResourceMark rm;
 544     _scratch_const_size = const_size;
 545     int size = C2Compiler::initial_code_buffer_size(const_size);
 546     blob = BufferBlob::create("Compile::scratch_buffer", size);
 547     // Record the buffer blob for next time.
 548     set_scratch_buffer_blob(blob);
 549     // Have we run out of code space?
 550     if (scratch_buffer_blob() == NULL) {
 551       // Let CompilerBroker disable further compilations.
 552       record_failure("Not enough space for scratch buffer in CodeCache");
 553       return;
 554     }
 555   }
 556 
 557   // Initialize the relocation buffers
 558   relocInfo* locs_buf = (relocInfo*) blob->content_end() - MAX_locs_size;
 559   set_scratch_locs_memory(locs_buf);
 560 }
 561 
 562 
 563 //-----------------------scratch_emit_size-------------------------------------
 564 // Helper function that computes size by emitting code
 565 uint Compile::scratch_emit_size(const Node* n) {
 566   // Start scratch_emit_size section.
 567   set_in_scratch_emit_size(true);
 568 
 569   // Emit into a trash buffer and count bytes emitted.
 570   // This is a pretty expensive way to compute a size,
 571   // but it works well enough if seldom used.
 572   // All common fixed-size instructions are given a size
 573   // method by the AD file.
 574   // Note that the scratch buffer blob and locs memory are
 575   // allocated at the beginning of the compile task, and
 576   // may be shared by several calls to scratch_emit_size.
 577   // The allocation of the scratch buffer blob is particularly
 578   // expensive, since it has to grab the code cache lock.
 579   BufferBlob* blob = this->scratch_buffer_blob();
 580   assert(blob != NULL, "Initialize BufferBlob at start");
 581   assert(blob->size() > MAX_inst_size, "sanity");
 582   relocInfo* locs_buf = scratch_locs_memory();
 583   address blob_begin = blob->content_begin();
 584   address blob_end   = (address)locs_buf;
 585   assert(blob->contains(blob_end), "sanity");
 586   CodeBuffer buf(blob_begin, blob_end - blob_begin);
 587   buf.initialize_consts_size(_scratch_const_size);
 588   buf.initialize_stubs_size(MAX_stubs_size);
 589   assert(locs_buf != NULL, "sanity");
 590   int lsize = MAX_locs_size / 3;
 591   buf.consts()->initialize_shared_locs(&locs_buf[lsize * 0], lsize);
 592   buf.insts()->initialize_shared_locs( &locs_buf[lsize * 1], lsize);
 593   buf.stubs()->initialize_shared_locs( &locs_buf[lsize * 2], lsize);
 594   // Mark as scratch buffer.
 595   buf.consts()->set_scratch_emit();
 596   buf.insts()->set_scratch_emit();
 597   buf.stubs()->set_scratch_emit();
 598 
 599   // Do the emission.
 600 
 601   Label fakeL; // Fake label for branch instructions.
 602   Label*   saveL = NULL;
 603   uint save_bnum = 0;
 604   bool is_branch = n->is_MachBranch();
 605   if (is_branch) {
 606     MacroAssembler masm(&buf);
 607     masm.bind(fakeL);
 608     n->as_MachBranch()->save_label(&saveL, &save_bnum);
 609     n->as_MachBranch()->label_set(&fakeL, 0);
 610   }
 611   n->emit(buf, this->regalloc());
 612 
 613   // Emitting into the scratch buffer should not fail
 614   assert (!failing(), "Must not have pending failure. Reason is: %s", failure_reason());
 615 
 616   if (is_branch) // Restore label.
 617     n->as_MachBranch()->label_set(saveL, save_bnum);
 618 
 619   // End scratch_emit_size section.
 620   set_in_scratch_emit_size(false);
 621 
 622   return buf.insts_size();
 623 }
 624 
 625 
 626 // ============================================================================
 627 //------------------------------Compile standard-------------------------------
 628 debug_only( int Compile::_debug_idx = 100000; )
 629 
 630 // Compile a method.  entry_bci is -1 for normal compilations and indicates
 631 // the continuation bci for on stack replacement.
 632 
 633 
 634 Compile::Compile( ciEnv* ci_env, C2Compiler* compiler, ciMethod* target, int osr_bci,
 635                   bool subsume_loads, bool do_escape_analysis, bool eliminate_boxing, DirectiveSet* directive)
 636                 : Phase(Compiler),
 637                   _compile_id(ci_env->compile_id()),
 638                   _save_argument_registers(false),
 639                   _subsume_loads(subsume_loads),
 640                   _do_escape_analysis(do_escape_analysis),
 641                   _eliminate_boxing(eliminate_boxing),
 642                   _method(target),
 643                   _entry_bci(osr_bci),
 644                   _stub_function(NULL),
 645                   _stub_name(NULL),
 646                   _stub_entry_point(NULL),
 647                   _max_node_limit(MaxNodeLimit),
 648                   _orig_pc_slot(0),
 649                   _orig_pc_slot_offset_in_bytes(0),
 650                   _inlining_progress(false),
 651                   _inlining_incrementally(false),
 652                   _do_cleanup(false),
 653                   _has_reserved_stack_access(target->has_reserved_stack_access()),
 654 #ifndef PRODUCT
 655                   _trace_opto_output(directive->TraceOptoOutputOption),
 656 #endif
 657                   _has_method_handle_invokes(false),
 658                   _comp_arena(mtCompiler),
 659                   _barrier_set_state(BarrierSet::barrier_set()->barrier_set_c2()->create_barrier_state(comp_arena())),
 660                   _env(ci_env),
 661                   _directive(directive),
 662                   _log(ci_env->log()),
 663                   _failure_reason(NULL),
 664                   _congraph(NULL),
 665 #ifndef PRODUCT
 666                   _printer(IdealGraphPrinter::printer()),
 667 #endif
 668                   _dead_node_list(comp_arena()),
 669                   _dead_node_count(0),
 670                   _node_arena(mtCompiler),
 671                   _old_arena(mtCompiler),
 672                   _mach_constant_base_node(NULL),
 673                   _Compile_types(mtCompiler),
 674                   _initial_gvn(NULL),
 675                   _for_igvn(NULL),
 676                   _warm_calls(NULL),
 677                   _late_inlines(comp_arena(), 2, 0, NULL),
 678                   _string_late_inlines(comp_arena(), 2, 0, NULL),
 679                   _boxing_late_inlines(comp_arena(), 2, 0, NULL),
 680                   _vector_reboxing_late_inlines(comp_arena(), 2, 0, NULL),
 681                   _late_inlines_pos(0),
 682                   _number_of_mh_late_inlines(0),
 683                   _print_inlining_stream(NULL),
 684                   _print_inlining_list(NULL),
 685                   _print_inlining_idx(0),
 686                   _print_inlining_output(NULL),
 687                   _replay_inline_data(NULL),
 688                   _java_calls(0),
 689                   _inner_loops(0),
 690                   _interpreter_frame_size(0),
 691                   _node_bundling_limit(0),
 692                   _node_bundling_base(NULL),
 693                   _code_buffer("Compile::Fill_buffer"),
 694                   _scratch_const_size(-1),
 695                   _in_scratch_emit_size(false)
 696 #ifndef PRODUCT
 697                   , _in_dump_cnt(0)
 698 #endif
 699 {
 700   C = this;
 701 #ifndef PRODUCT
 702   if (_printer != NULL) {
 703     _printer->set_compile(this);
 704   }
 705 #endif
 706   CompileWrapper cw(this);
 707 
 708   if (CITimeVerbose) {
 709     tty->print(" ");
 710     target->holder()->name()->print();
 711     tty->print(".");
 712     target->print_short_name();
 713     tty->print("  ");
 714   }
 715   TraceTime t1("Total compilation time", &_t_totalCompilation, CITime, CITimeVerbose);
 716   TraceTime t2(NULL, &_t_methodCompilation, CITime, false);
 717 
 718 #ifndef PRODUCT
 719   bool print_opto_assembly = directive->PrintOptoAssemblyOption;
 720   if (!print_opto_assembly) {
 721     bool print_assembly = directive->PrintAssemblyOption;
 722     if (print_assembly && !Disassembler::can_decode()) {
 723       tty->print_cr("PrintAssembly request changed to PrintOptoAssembly");
 724       print_opto_assembly = true;
 725     }
 726   }
 727   set_print_assembly(print_opto_assembly);
 728   set_parsed_irreducible_loop(false);
 729 
 730   if (directive->ReplayInlineOption) {
 731     _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
 732   }
 733 #endif
 734   set_print_inlining(directive->PrintInliningOption || PrintOptoInlining);
 735   set_print_intrinsics(directive->PrintIntrinsicsOption);
 736   set_has_irreducible_loop(true); // conservative until build_loop_tree() reset it
 737 
 738   if (ProfileTraps RTM_OPT_ONLY( || UseRTMLocking )) {
 739     // Make sure the method being compiled gets its own MDO,
 740     // so we can at least track the decompile_count().
 741     // Need MDO to record RTM code generation state.
 742     method()->ensure_method_data();
 743   }
 744 
 745   Init(::AliasLevel);
 746 
 747 
 748   print_compile_messages();
 749 
 750   _ilt = InlineTree::build_inline_tree_root();
 751 
 752   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
 753   assert(num_alias_types() >= AliasIdxRaw, "");
 754 
 755 #define MINIMUM_NODE_HASH  1023
 756   // Node list that Iterative GVN will start with
 757   Unique_Node_List for_igvn(comp_arena());
 758   set_for_igvn(&for_igvn);
 759 
 760   // GVN that will be run immediately on new nodes
 761   uint estimated_size = method()->code_size()*4+64;
 762   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
 763   PhaseGVN gvn(node_arena(), estimated_size);
 764   set_initial_gvn(&gvn);
 765 
 766   print_inlining_init();
 767   { // Scope for timing the parser
 768     TracePhase tp("parse", &timers[_t_parser]);
 769 
 770     // Put top into the hash table ASAP.
 771     initial_gvn()->transform_no_reclaim(top());
 772 
 773     // Set up tf(), start(), and find a CallGenerator.
 774     CallGenerator* cg = NULL;
 775     if (is_osr_compilation()) {
 776       const TypeTuple *domain = StartOSRNode::osr_domain();
 777       const TypeTuple *range = TypeTuple::make_range(method()->signature());
 778       init_tf(TypeFunc::make(domain, range));
 779       StartNode* s = new StartOSRNode(root(), domain);
 780       initial_gvn()->set_type_bottom(s);
 781       init_start(s);
 782       cg = CallGenerator::for_osr(method(), entry_bci());
 783     } else {
 784       // Normal case.
 785       init_tf(TypeFunc::make(method()));
 786       StartNode* s = new StartNode(root(), tf()->domain());
 787       initial_gvn()->set_type_bottom(s);
 788       init_start(s);
 789       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get) {
 790         // With java.lang.ref.reference.get() we must go through the
 791         // intrinsic - even when get() is the root
 792         // method of the compile - so that, if necessary, the value in
 793         // the referent field of the reference object gets recorded by
 794         // the pre-barrier code.
 795         cg = find_intrinsic(method(), false);
 796       }
 797       if (cg == NULL) {
 798         float past_uses = method()->interpreter_invocation_count();
 799         float expected_uses = past_uses;
 800         cg = CallGenerator::for_inline(method(), expected_uses);
 801       }
 802     }
 803     if (failing())  return;
 804     if (cg == NULL) {
 805       record_method_not_compilable("cannot parse method");
 806       return;
 807     }
 808     JVMState* jvms = build_start_state(start(), tf());
 809     if ((jvms = cg->generate(jvms)) == NULL) {
 810       if (!failure_reason_is(C2Compiler::retry_class_loading_during_parsing())) {
 811         record_method_not_compilable("method parse failed");
 812       }
 813       return;
 814     }
 815     GraphKit kit(jvms);
 816 
 817     if (!kit.stopped()) {
 818       // Accept return values, and transfer control we know not where.
 819       // This is done by a special, unique ReturnNode bound to root.
 820       return_values(kit.jvms());
 821     }
 822 
 823     if (kit.has_exceptions()) {
 824       // Any exceptions that escape from this call must be rethrown
 825       // to whatever caller is dynamically above us on the stack.
 826       // This is done by a special, unique RethrowNode bound to root.
 827       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
 828     }
 829 
 830     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
 831 
 832     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
 833       inline_string_calls(true);
 834     }
 835 
 836     if (failing())  return;
 837 
 838     print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
 839 
 840     // Remove clutter produced by parsing.
 841     if (!failing()) {
 842       ResourceMark rm;
 843       PhaseRemoveUseless pru(initial_gvn(), &for_igvn);
 844     }
 845   }
 846 
 847   // Note:  Large methods are capped off in do_one_bytecode().
 848   if (failing())  return;
 849 
 850   // After parsing, node notes are no longer automagic.
 851   // They must be propagated by register_new_node_with_optimizer(),
 852   // clone(), or the like.
 853   set_default_node_notes(NULL);
 854 
 855   for (;;) {
 856     int successes = Inline_Warm();
 857     if (failing())  return;
 858     if (successes == 0)  break;
 859   }
 860 
 861   // Drain the list.
 862   Finish_Warm();
 863 #ifndef PRODUCT
 864   if (_printer && _printer->should_print(1)) {
 865     _printer->print_inlining();
 866   }
 867 #endif
 868 
 869   if (failing())  return;
 870   NOT_PRODUCT( verify_graph_edges(); )
 871 
 872   // Now optimize
 873   Optimize();
 874   if (failing())  return;
 875   NOT_PRODUCT( verify_graph_edges(); )
 876 
 877 #ifndef PRODUCT
 878   if (PrintIdeal) {
 879     ttyLocker ttyl;  // keep the following output all in one block
 880     // This output goes directly to the tty, not the compiler log.
 881     // To enable tools to match it up with the compilation activity,
 882     // be sure to tag this tty output with the compile ID.
 883     if (xtty != NULL) {
 884       xtty->head("ideal compile_id='%d'%s", compile_id(),
 885                  is_osr_compilation()    ? " compile_kind='osr'" :
 886                  "");
 887     }
 888     root()->dump(9999);
 889     if (xtty != NULL) {
 890       xtty->tail("ideal");
 891     }
 892   }
 893 #endif
 894 
 895 #ifdef ASSERT
 896   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 897   bs->verify_gc_barriers(this, BarrierSetC2::BeforeCodeGen);
 898 #endif
 899 
 900   // Dump compilation data to replay it.
 901   if (directive->DumpReplayOption) {
 902     env()->dump_replay_data(_compile_id);
 903   }
 904   if (directive->DumpInlineOption && (ilt() != NULL)) {
 905     env()->dump_inline_data(_compile_id);
 906   }
 907 
 908   // Now that we know the size of all the monitors we can add a fixed slot
 909   // for the original deopt pc.
 910 
 911   _orig_pc_slot =  fixed_slots();
 912   int next_slot = _orig_pc_slot + (sizeof(address) / VMRegImpl::stack_slot_size);
 913   set_fixed_slots(next_slot);
 914 
 915   // Compute when to use implicit null checks. Used by matching trap based
 916   // nodes and NullCheck optimization.
 917   set_allowed_deopt_reasons();
 918 
 919   // Now generate code
 920   Code_Gen();
 921   if (failing())  return;
 922 
 923   // Check if we want to skip execution of all compiled code.
 924   {
 925 #ifndef PRODUCT
 926     if (OptoNoExecute) {
 927       record_method_not_compilable("+OptoNoExecute");  // Flag as failed
 928       return;
 929     }
 930 #endif
 931     TracePhase tp("install_code", &timers[_t_registerMethod]);
 932 
 933     if (is_osr_compilation()) {
 934       _code_offsets.set_value(CodeOffsets::Verified_Entry, 0);
 935       _code_offsets.set_value(CodeOffsets::OSR_Entry, _first_block_size);
 936     } else {
 937       _code_offsets.set_value(CodeOffsets::Verified_Entry, _first_block_size);
 938       _code_offsets.set_value(CodeOffsets::OSR_Entry, 0);
 939     }
 940 
 941     env()->register_method(_method, _entry_bci,
 942                            &_code_offsets,
 943                            _orig_pc_slot_offset_in_bytes,
 944                            code_buffer(),
 945                            frame_size_in_words(), _oop_map_set,
 946                            &_handler_table, &_inc_table,
 947                            compiler,
 948                            has_unsafe_access(),
 949                            SharedRuntime::is_wide_vector(max_vector_size()),
 950                            rtm_state()
 951                            );
 952 
 953     if (log() != NULL) // Print code cache state into compiler log
 954       log()->code_cache_state();
 955   }
 956 }
 957 
 958 //------------------------------Compile----------------------------------------
 959 // Compile a runtime stub
 960 Compile::Compile( ciEnv* ci_env,
 961                   TypeFunc_generator generator,
 962                   address stub_function,
 963                   const char *stub_name,
 964                   int is_fancy_jump,
 965                   bool pass_tls,
 966                   bool save_arg_registers,
 967                   bool return_pc,
 968                   DirectiveSet* directive)
 969   : Phase(Compiler),
 970     _compile_id(0),
 971     _save_argument_registers(save_arg_registers),
 972     _subsume_loads(true),
 973     _do_escape_analysis(false),
 974     _eliminate_boxing(false),
 975     _method(NULL),
 976     _entry_bci(InvocationEntryBci),
 977     _stub_function(stub_function),
 978     _stub_name(stub_name),
 979     _stub_entry_point(NULL),
 980     _max_node_limit(MaxNodeLimit),
 981     _orig_pc_slot(0),
 982     _orig_pc_slot_offset_in_bytes(0),
 983     _inlining_progress(false),
 984     _inlining_incrementally(false),
 985     _has_reserved_stack_access(false),
 986 #ifndef PRODUCT
 987     _trace_opto_output(directive->TraceOptoOutputOption),
 988 #endif
 989     _has_method_handle_invokes(false),
 990     _comp_arena(mtCompiler),
 991     _env(ci_env),
 992     _directive(directive),
 993     _log(ci_env->log()),
 994     _failure_reason(NULL),
 995     _congraph(NULL),
 996 #ifndef PRODUCT
 997     _printer(NULL),
 998 #endif
 999     _dead_node_list(comp_arena()),
1000     _dead_node_count(0),
1001     _node_arena(mtCompiler),
1002     _old_arena(mtCompiler),
1003     _mach_constant_base_node(NULL),
1004     _Compile_types(mtCompiler),
1005     _initial_gvn(NULL),
1006     _for_igvn(NULL),
1007     _warm_calls(NULL),
1008     _number_of_mh_late_inlines(0),
1009     _print_inlining_stream(NULL),
1010     _print_inlining_list(NULL),
1011     _print_inlining_idx(0),
1012     _print_inlining_output(NULL),
1013     _replay_inline_data(NULL),
1014     _java_calls(0),
1015     _inner_loops(0),
1016     _interpreter_frame_size(0),
1017     _node_bundling_limit(0),
1018     _node_bundling_base(NULL),
1019     _code_buffer("Compile::Fill_buffer"),
1020 #ifndef PRODUCT
1021     _in_dump_cnt(0),
1022 #endif
1023     _allowed_reasons(0) {
1024   C = this;
1025 
1026   TraceTime t1(NULL, &_t_totalCompilation, CITime, false);
1027   TraceTime t2(NULL, &_t_stubCompilation, CITime, false);
1028 
1029 #ifndef PRODUCT
1030   set_print_assembly(PrintFrameConverterAssembly);
1031   set_parsed_irreducible_loop(false);
1032 #endif
1033   set_has_irreducible_loop(false); // no loops
1034 
1035   CompileWrapper cw(this);
1036   Init(/*AliasLevel=*/ 0);
1037   init_tf((*generator)());
1038 
1039   {
1040     // The following is a dummy for the sake of GraphKit::gen_stub
1041     Unique_Node_List for_igvn(comp_arena());
1042     set_for_igvn(&for_igvn);  // not used, but some GraphKit guys push on this
1043     PhaseGVN gvn(Thread::current()->resource_area(),255);
1044     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
1045     gvn.transform_no_reclaim(top());
1046 
1047     GraphKit kit;
1048     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
1049   }
1050 
1051   NOT_PRODUCT( verify_graph_edges(); )
1052   Code_Gen();
1053   if (failing())  return;
1054 
1055 
1056   // Entry point will be accessed using compile->stub_entry_point();
1057   if (code_buffer() == NULL) {
1058     Matcher::soft_match_failure();
1059   } else {
1060     if (PrintAssembly && (WizardMode || Verbose))
1061       tty->print_cr("### Stub::%s", stub_name);
1062 
1063     if (!failing()) {
1064       assert(_fixed_slots == 0, "no fixed slots used for runtime stubs");
1065 
1066       // Make the NMethod
1067       // For now we mark the frame as never safe for profile stackwalking
1068       RuntimeStub *rs = RuntimeStub::new_runtime_stub(stub_name,
1069                                                       code_buffer(),
1070                                                       CodeOffsets::frame_never_safe,
1071                                                       // _code_offsets.value(CodeOffsets::Frame_Complete),
1072                                                       frame_size_in_words(),
1073                                                       _oop_map_set,
1074                                                       save_arg_registers);
1075       assert(rs != NULL && rs->is_runtime_stub(), "sanity check");
1076 
1077       _stub_entry_point = rs->entry_point();
1078     }
1079   }
1080 }
1081 
1082 //------------------------------Init-------------------------------------------
1083 // Prepare for a single compilation
1084 void Compile::Init(int aliaslevel) {
1085   _unique  = 0;
1086   _regalloc = NULL;
1087 
1088   _tf      = NULL;  // filled in later
1089   _top     = NULL;  // cached later
1090   _matcher = NULL;  // filled in later
1091   _cfg     = NULL;  // filled in later
1092 
1093   set_24_bit_selection_and_mode(Use24BitFP, false);
1094 
1095   _node_note_array = NULL;
1096   _default_node_notes = NULL;
1097   DEBUG_ONLY( _modified_nodes = NULL; ) // Used in Optimize()
1098 
1099   _immutable_memory = NULL; // filled in at first inquiry
1100 
1101   // Globally visible Nodes
1102   // First set TOP to NULL to give safe behavior during creation of RootNode
1103   set_cached_top_node(NULL);
1104   set_root(new RootNode());
1105   // Now that you have a Root to point to, create the real TOP
1106   set_cached_top_node( new ConNode(Type::TOP) );
1107   set_recent_alloc(NULL, NULL);
1108 
1109   // Create Debug Information Recorder to record scopes, oopmaps, etc.
1110   env()->set_oop_recorder(new OopRecorder(env()->arena()));
1111   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
1112   env()->set_dependencies(new Dependencies(env()));
1113 
1114   _fixed_slots = 0;
1115   set_has_split_ifs(false);
1116   set_has_loops(has_method() && method()->has_loops()); // first approximation
1117   set_has_stringbuilder(false);
1118   set_has_boxed_value(false);
1119   _trap_can_recompile = false;  // no traps emitted yet
1120   _major_progress = true; // start out assuming good things will happen
1121   set_has_unsafe_access(false);
1122   set_max_vector_size(0);
1123   set_clear_upper_avx(false);  //false as default for clear upper bits of ymm registers
1124   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
1125   set_decompile_count(0);
1126 
1127   set_do_freq_based_layout(_directive->BlockLayoutByFrequencyOption);
1128   _loop_opts_cnt = LoopOptsCount;
1129   set_do_inlining(Inline);
1130   set_max_inline_size(MaxInlineSize);
1131   set_freq_inline_size(FreqInlineSize);
1132   set_do_scheduling(OptoScheduling);
1133   set_do_count_invocations(false);
1134   set_do_method_data_update(false);
1135 
1136   set_do_vector_loop(false);
1137 
1138   if (AllowVectorizeOnDemand) {
1139     if (has_method() && (_directive->VectorizeOption || _directive->VectorizeDebugOption)) {
1140       set_do_vector_loop(true);
1141       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());})
1142     } else if (has_method() && method()->name() != 0 &&
1143                method()->intrinsic_id() == vmIntrinsics::_forEachRemaining) {
1144       set_do_vector_loop(true);
1145     }
1146   }
1147   set_use_cmove(UseCMoveUnconditionally /* || do_vector_loop()*/); //TODO: consider do_vector_loop() mandate use_cmove unconditionally
1148   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());})
1149 
1150   set_age_code(has_method() && method()->profile_aging());
1151   set_rtm_state(NoRTM); // No RTM lock eliding by default
1152   _max_node_limit = _directive->MaxNodeLimitOption;
1153 
1154 #if INCLUDE_RTM_OPT
1155   if (UseRTMLocking && has_method() && (method()->method_data_or_null() != NULL)) {
1156     int rtm_state = method()->method_data()->rtm_state();
1157     if (method_has_option("NoRTMLockEliding") || ((rtm_state & NoRTM) != 0)) {
1158       // Don't generate RTM lock eliding code.
1159       set_rtm_state(NoRTM);
1160     } else if (method_has_option("UseRTMLockEliding") || ((rtm_state & UseRTM) != 0) || !UseRTMDeopt) {
1161       // Generate RTM lock eliding code without abort ratio calculation code.
1162       set_rtm_state(UseRTM);
1163     } else if (UseRTMDeopt) {
1164       // Generate RTM lock eliding code and include abort ratio calculation
1165       // code if UseRTMDeopt is on.
1166       set_rtm_state(ProfileRTM);
1167     }
1168   }
1169 #endif
1170   if (debug_info()->recording_non_safepoints()) {
1171     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
1172                         (comp_arena(), 8, 0, NULL));
1173     set_default_node_notes(Node_Notes::make(this));
1174   }
1175 
1176   // // -- Initialize types before each compile --
1177   // // Update cached type information
1178   // if( _method && _method->constants() )
1179   //   Type::update_loaded_types(_method, _method->constants());
1180 
1181   // Init alias_type map.
1182   if (!_do_escape_analysis && aliaslevel == 3)
1183     aliaslevel = 2;  // No unique types without escape analysis
1184   _AliasLevel = aliaslevel;
1185   const int grow_ats = 16;
1186   _max_alias_types = grow_ats;
1187   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1188   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
1189   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1190   {
1191     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
1192   }
1193   // Initialize the first few types.
1194   _alias_types[AliasIdxTop]->Init(AliasIdxTop, NULL);
1195   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1196   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1197   _num_alias_types = AliasIdxRaw+1;
1198   // Zero out the alias type cache.
1199   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1200   // A NULL adr_type hits in the cache right away.  Preload the right answer.
1201   probe_alias_cache(NULL)->_index = AliasIdxTop;
1202 
1203   _intrinsics = NULL;
1204   _macro_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1205   _predicate_opaqs = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1206   _expensive_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1207   _range_check_casts = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1208   _opaque4_nodes = new(comp_arena()) GrowableArray<Node*>(comp_arena(), 8,  0, NULL);
1209   register_library_intrinsics();
1210 }
1211 
1212 //---------------------------init_start----------------------------------------
1213 // Install the StartNode on this compile object.
1214 void Compile::init_start(StartNode* s) {
1215   if (failing())
1216     return; // already failing
1217   assert(s == start(), "");
1218 }
1219 
1220 /**
1221  * Return the 'StartNode'. We must not have a pending failure, since the ideal graph
1222  * can be in an inconsistent state, i.e., we can get segmentation faults when traversing
1223  * the ideal graph.
1224  */
1225 StartNode* Compile::start() const {
1226   assert (!failing(), "Must not have pending failure. Reason is: %s", failure_reason());
1227   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1228     Node* start = root()->fast_out(i);
1229     if (start->is_Start()) {
1230       return start->as_Start();
1231     }
1232   }
1233   fatal("Did not find Start node!");
1234   return NULL;
1235 }
1236 
1237 //-------------------------------immutable_memory-------------------------------------
1238 // Access immutable memory
1239 Node* Compile::immutable_memory() {
1240   if (_immutable_memory != NULL) {
1241     return _immutable_memory;
1242   }
1243   StartNode* s = start();
1244   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1245     Node *p = s->fast_out(i);
1246     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1247       _immutable_memory = p;
1248       return _immutable_memory;
1249     }
1250   }
1251   ShouldNotReachHere();
1252   return NULL;
1253 }
1254 
1255 //----------------------set_cached_top_node------------------------------------
1256 // Install the cached top node, and make sure Node::is_top works correctly.
1257 void Compile::set_cached_top_node(Node* tn) {
1258   if (tn != NULL)  verify_top(tn);
1259   Node* old_top = _top;
1260   _top = tn;
1261   // Calling Node::setup_is_top allows the nodes the chance to adjust
1262   // their _out arrays.
1263   if (_top != NULL)     _top->setup_is_top();
1264   if (old_top != NULL)  old_top->setup_is_top();
1265   assert(_top == NULL || top()->is_top(), "");
1266 }
1267 
1268 #ifdef ASSERT
1269 uint Compile::count_live_nodes_by_graph_walk() {
1270   Unique_Node_List useful(comp_arena());
1271   // Get useful node list by walking the graph.
1272   identify_useful_nodes(useful);
1273   return useful.size();
1274 }
1275 
1276 void Compile::print_missing_nodes() {
1277 
1278   // Return if CompileLog is NULL and PrintIdealNodeCount is false.
1279   if ((_log == NULL) && (! PrintIdealNodeCount)) {
1280     return;
1281   }
1282 
1283   // This is an expensive function. It is executed only when the user
1284   // specifies VerifyIdealNodeCount option or otherwise knows the
1285   // additional work that needs to be done to identify reachable nodes
1286   // by walking the flow graph and find the missing ones using
1287   // _dead_node_list.
1288 
1289   Unique_Node_List useful(comp_arena());
1290   // Get useful node list by walking the graph.
1291   identify_useful_nodes(useful);
1292 
1293   uint l_nodes = C->live_nodes();
1294   uint l_nodes_by_walk = useful.size();
1295 
1296   if (l_nodes != l_nodes_by_walk) {
1297     if (_log != NULL) {
1298       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
1299       _log->stamp();
1300       _log->end_head();
1301     }
1302     VectorSet& useful_member_set = useful.member_set();
1303     int last_idx = l_nodes_by_walk;
1304     for (int i = 0; i < last_idx; i++) {
1305       if (useful_member_set.test(i)) {
1306         if (_dead_node_list.test(i)) {
1307           if (_log != NULL) {
1308             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
1309           }
1310           if (PrintIdealNodeCount) {
1311             // Print the log message to tty
1312               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
1313               useful.at(i)->dump();
1314           }
1315         }
1316       }
1317       else if (! _dead_node_list.test(i)) {
1318         if (_log != NULL) {
1319           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
1320         }
1321         if (PrintIdealNodeCount) {
1322           // Print the log message to tty
1323           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
1324         }
1325       }
1326     }
1327     if (_log != NULL) {
1328       _log->tail("mismatched_nodes");
1329     }
1330   }
1331 }
1332 void Compile::record_modified_node(Node* n) {
1333   if (_modified_nodes != NULL && !_inlining_incrementally &&
1334       n->outcnt() != 0 && !n->is_Con()) {
1335     _modified_nodes->push(n);
1336   }
1337 }
1338 
1339 void Compile::remove_modified_node(Node* n) {
1340   if (_modified_nodes != NULL) {
1341     _modified_nodes->remove(n);
1342   }
1343 }
1344 #endif
1345 
1346 #ifndef PRODUCT
1347 void Compile::verify_top(Node* tn) const {
1348   if (tn != NULL) {
1349     assert(tn->is_Con(), "top node must be a constant");
1350     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1351     assert(tn->in(0) != NULL, "must have live top node");
1352   }
1353 }
1354 #endif
1355 
1356 
1357 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1358 
1359 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1360   guarantee(arr != NULL, "");
1361   int num_blocks = arr->length();
1362   if (grow_by < num_blocks)  grow_by = num_blocks;
1363   int num_notes = grow_by * _node_notes_block_size;
1364   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1365   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1366   while (num_notes > 0) {
1367     arr->append(notes);
1368     notes     += _node_notes_block_size;
1369     num_notes -= _node_notes_block_size;
1370   }
1371   assert(num_notes == 0, "exact multiple, please");
1372 }
1373 
1374 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1375   if (source == NULL || dest == NULL)  return false;
1376 
1377   if (dest->is_Con())
1378     return false;               // Do not push debug info onto constants.
1379 
1380 #ifdef ASSERT
1381   // Leave a bread crumb trail pointing to the original node:
1382   if (dest != NULL && dest != source && dest->debug_orig() == NULL) {
1383     dest->set_debug_orig(source);
1384   }
1385 #endif
1386 
1387   if (node_note_array() == NULL)
1388     return false;               // Not collecting any notes now.
1389 
1390   // This is a copy onto a pre-existing node, which may already have notes.
1391   // If both nodes have notes, do not overwrite any pre-existing notes.
1392   Node_Notes* source_notes = node_notes_at(source->_idx);
1393   if (source_notes == NULL || source_notes->is_clear())  return false;
1394   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
1395   if (dest_notes == NULL || dest_notes->is_clear()) {
1396     return set_node_notes_at(dest->_idx, source_notes);
1397   }
1398 
1399   Node_Notes merged_notes = (*source_notes);
1400   // The order of operations here ensures that dest notes will win...
1401   merged_notes.update_from(dest_notes);
1402   return set_node_notes_at(dest->_idx, &merged_notes);
1403 }
1404 
1405 
1406 //--------------------------allow_range_check_smearing-------------------------
1407 // Gating condition for coalescing similar range checks.
1408 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1409 // single covering check that is at least as strong as any of them.
1410 // If the optimization succeeds, the simplified (strengthened) range check
1411 // will always succeed.  If it fails, we will deopt, and then give up
1412 // on the optimization.
1413 bool Compile::allow_range_check_smearing() const {
1414   // If this method has already thrown a range-check,
1415   // assume it was because we already tried range smearing
1416   // and it failed.
1417   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1418   return !already_trapped;
1419 }
1420 
1421 
1422 //------------------------------flatten_alias_type-----------------------------
1423 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1424   int offset = tj->offset();
1425   TypePtr::PTR ptr = tj->ptr();
1426 
1427   // Known instance (scalarizable allocation) alias only with itself.
1428   bool is_known_inst = tj->isa_oopptr() != NULL &&
1429                        tj->is_oopptr()->is_known_instance();
1430 
1431   // Process weird unsafe references.
1432   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1433     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
1434     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1435     tj = TypeOopPtr::BOTTOM;
1436     ptr = tj->ptr();
1437     offset = tj->offset();
1438   }
1439 
1440   // Array pointers need some flattening
1441   const TypeAryPtr *ta = tj->isa_aryptr();
1442   if (ta && ta->is_stable()) {
1443     // Erase stability property for alias analysis.
1444     tj = ta = ta->cast_to_stable(false);
1445   }
1446   if( ta && is_known_inst ) {
1447     if ( offset != Type::OffsetBot &&
1448          offset > arrayOopDesc::length_offset_in_bytes() ) {
1449       offset = Type::OffsetBot; // Flatten constant access into array body only
1450       tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
1451     }
1452   } else if( ta && _AliasLevel >= 2 ) {
1453     // For arrays indexed by constant indices, we flatten the alias
1454     // space to include all of the array body.  Only the header, klass
1455     // and array length can be accessed un-aliased.
1456     if( offset != Type::OffsetBot ) {
1457       if( ta->const_oop() ) { // MethodData* or Method*
1458         offset = Type::OffsetBot;   // Flatten constant access into array body
1459         tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
1460       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1461         // range is OK as-is.
1462         tj = ta = TypeAryPtr::RANGE;
1463       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1464         tj = TypeInstPtr::KLASS; // all klass loads look alike
1465         ta = TypeAryPtr::RANGE; // generic ignored junk
1466         ptr = TypePtr::BotPTR;
1467       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1468         tj = TypeInstPtr::MARK;
1469         ta = TypeAryPtr::RANGE; // generic ignored junk
1470         ptr = TypePtr::BotPTR;
1471       } else if (BarrierSet::barrier_set()->barrier_set_c2()->flatten_gc_alias_type(tj)) {
1472         ta = tj->isa_aryptr();
1473       } else {                  // Random constant offset into array body
1474         offset = Type::OffsetBot;   // Flatten constant access into array body
1475         tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
1476       }
1477     }
1478     // Arrays of fixed size alias with arrays of unknown size.
1479     if (ta->size() != TypeInt::POS) {
1480       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1481       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
1482     }
1483     // Arrays of known objects become arrays of unknown objects.
1484     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1485       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1486       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1487     }
1488     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1489       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1490       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
1491     }
1492     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1493     // cannot be distinguished by bytecode alone.
1494     if (ta->elem() == TypeInt::BOOL) {
1495       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1496       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1497       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
1498     }
1499     // During the 2nd round of IterGVN, NotNull castings are removed.
1500     // Make sure the Bottom and NotNull variants alias the same.
1501     // Also, make sure exact and non-exact variants alias the same.
1502     if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != NULL) {
1503       tj = ta = TypeAryPtr::make(TypePtr::BotPTR,ta->ary(),ta->klass(),false,offset);
1504     }
1505   }
1506 
1507   // Oop pointers need some flattening
1508   const TypeInstPtr *to = tj->isa_instptr();
1509   if( to && _AliasLevel >= 2 && to != TypeOopPtr::BOTTOM ) {
1510     ciInstanceKlass *k = to->klass()->as_instance_klass();
1511     if( ptr == TypePtr::Constant ) {
1512       if (to->klass() != ciEnv::current()->Class_klass() ||
1513           offset < k->size_helper() * wordSize) {
1514         // No constant oop pointers (such as Strings); they alias with
1515         // unknown strings.
1516         assert(!is_known_inst, "not scalarizable allocation");
1517         tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1518       }
1519     } else if( is_known_inst ) {
1520       tj = to; // Keep NotNull and klass_is_exact for instance type
1521     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1522       // During the 2nd round of IterGVN, NotNull castings are removed.
1523       // Make sure the Bottom and NotNull variants alias the same.
1524       // Also, make sure exact and non-exact variants alias the same.
1525       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
1526     }
1527     if (to->speculative() != NULL) {
1528       tj = to = TypeInstPtr::make(to->ptr(),to->klass(),to->klass_is_exact(),to->const_oop(),to->offset(), to->instance_id());
1529     }
1530     // Canonicalize the holder of this field
1531     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1532       // First handle header references such as a LoadKlassNode, even if the
1533       // object's klass is unloaded at compile time (4965979).
1534       if (!is_known_inst) { // Do it only for non-instance types
1535         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
1536       }
1537     } else if (BarrierSet::barrier_set()->barrier_set_c2()->flatten_gc_alias_type(tj)) {
1538       to = tj->is_instptr();
1539     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
1540       // Static fields are in the space above the normal instance
1541       // fields in the java.lang.Class instance.
1542       if (to->klass() != ciEnv::current()->Class_klass()) {
1543         to = NULL;
1544         tj = TypeOopPtr::BOTTOM;
1545         offset = tj->offset();
1546       }
1547     } else {
1548       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
1549       if (!k->equals(canonical_holder) || tj->offset() != offset) {
1550         if( is_known_inst ) {
1551           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
1552         } else {
1553           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
1554         }
1555       }
1556     }
1557   }
1558 
1559   // Klass pointers to object array klasses need some flattening
1560   const TypeKlassPtr *tk = tj->isa_klassptr();
1561   if( tk ) {
1562     // If we are referencing a field within a Klass, we need
1563     // to assume the worst case of an Object.  Both exact and
1564     // inexact types must flatten to the same alias class so
1565     // use NotNull as the PTR.
1566     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1567 
1568       tj = tk = TypeKlassPtr::make(TypePtr::NotNull,
1569                                    TypeKlassPtr::OBJECT->klass(),
1570                                    offset);
1571     }
1572 
1573     ciKlass* klass = tk->klass();
1574     if( klass->is_obj_array_klass() ) {
1575       ciKlass* k = TypeAryPtr::OOPS->klass();
1576       if( !k || !k->is_loaded() )                  // Only fails for some -Xcomp runs
1577         k = TypeInstPtr::BOTTOM->klass();
1578       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, k, offset );
1579     }
1580 
1581     // Check for precise loads from the primary supertype array and force them
1582     // to the supertype cache alias index.  Check for generic array loads from
1583     // the primary supertype array and also force them to the supertype cache
1584     // alias index.  Since the same load can reach both, we need to merge
1585     // these 2 disparate memories into the same alias class.  Since the
1586     // primary supertype array is read-only, there's no chance of confusion
1587     // where we bypass an array load and an array store.
1588     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1589     if (offset == Type::OffsetBot ||
1590         (offset >= primary_supers_offset &&
1591          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1592         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1593       offset = in_bytes(Klass::secondary_super_cache_offset());
1594       tj = tk = TypeKlassPtr::make( TypePtr::NotNull, tk->klass(), offset );
1595     }
1596   }
1597 
1598   // Flatten all Raw pointers together.
1599   if (tj->base() == Type::RawPtr)
1600     tj = TypeRawPtr::BOTTOM;
1601 
1602   if (tj->base() == Type::AnyPtr)
1603     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
1604 
1605   // Flatten all to bottom for now
1606   switch( _AliasLevel ) {
1607   case 0:
1608     tj = TypePtr::BOTTOM;
1609     break;
1610   case 1:                       // Flatten to: oop, static, field or array
1611     switch (tj->base()) {
1612     //case Type::AryPtr: tj = TypeAryPtr::RANGE;    break;
1613     case Type::RawPtr:   tj = TypeRawPtr::BOTTOM;   break;
1614     case Type::AryPtr:   // do not distinguish arrays at all
1615     case Type::InstPtr:  tj = TypeInstPtr::BOTTOM;  break;
1616     case Type::KlassPtr: tj = TypeKlassPtr::OBJECT; break;
1617     case Type::AnyPtr:   tj = TypePtr::BOTTOM;      break;  // caller checks it
1618     default: ShouldNotReachHere();
1619     }
1620     break;
1621   case 2:                       // No collapsing at level 2; keep all splits
1622   case 3:                       // No collapsing at level 3; keep all splits
1623     break;
1624   default:
1625     Unimplemented();
1626   }
1627 
1628   offset = tj->offset();
1629   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1630 
1631   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1632           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1633           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1634           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1635           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1636           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1637           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1638           (BarrierSet::barrier_set()->barrier_set_c2()->verify_gc_alias_type(tj, offset)),
1639           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1640   assert( tj->ptr() != TypePtr::TopPTR &&
1641           tj->ptr() != TypePtr::AnyNull &&
1642           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1643 //    assert( tj->ptr() != TypePtr::Constant ||
1644 //            tj->base() == Type::RawPtr ||
1645 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
1646 
1647   return tj;
1648 }
1649 
1650 void Compile::AliasType::Init(int i, const TypePtr* at) {
1651   _index = i;
1652   _adr_type = at;
1653   _field = NULL;
1654   _element = NULL;
1655   _is_rewritable = true; // default
1656   const TypeOopPtr *atoop = (at != NULL) ? at->isa_oopptr() : NULL;
1657   if (atoop != NULL && atoop->is_known_instance()) {
1658     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1659     _general_index = Compile::current()->get_alias_index(gt);
1660   } else {
1661     _general_index = 0;
1662   }
1663 }
1664 
1665 BasicType Compile::AliasType::basic_type() const {
1666   if (element() != NULL) {
1667     const Type* element = adr_type()->is_aryptr()->elem();
1668     return element->isa_narrowoop() ? T_OBJECT : element->array_element_basic_type();
1669   } if (field() != NULL) {
1670     return field()->layout_type();
1671   } else {
1672     return T_ILLEGAL; // unknown
1673   }
1674 }
1675 
1676 //---------------------------------print_on------------------------------------
1677 #ifndef PRODUCT
1678 void Compile::AliasType::print_on(outputStream* st) {
1679   if (index() < 10)
1680         st->print("@ <%d> ", index());
1681   else  st->print("@ <%d>",  index());
1682   st->print(is_rewritable() ? "   " : " RO");
1683   int offset = adr_type()->offset();
1684   if (offset == Type::OffsetBot)
1685         st->print(" +any");
1686   else  st->print(" +%-3d", offset);
1687   st->print(" in ");
1688   adr_type()->dump_on(st);
1689   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1690   if (field() != NULL && tjp) {
1691     if (tjp->klass()  != field()->holder() ||
1692         tjp->offset() != field()->offset_in_bytes()) {
1693       st->print(" != ");
1694       field()->print();
1695       st->print(" ***");
1696     }
1697   }
1698 }
1699 
1700 void print_alias_types() {
1701   Compile* C = Compile::current();
1702   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1703   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1704     C->alias_type(idx)->print_on(tty);
1705     tty->cr();
1706   }
1707 }
1708 #endif
1709 
1710 
1711 //----------------------------probe_alias_cache--------------------------------
1712 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1713   intptr_t key = (intptr_t) adr_type;
1714   key ^= key >> logAliasCacheSize;
1715   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1716 }
1717 
1718 
1719 //-----------------------------grow_alias_types--------------------------------
1720 void Compile::grow_alias_types() {
1721   const int old_ats  = _max_alias_types; // how many before?
1722   const int new_ats  = old_ats;          // how many more?
1723   const int grow_ats = old_ats+new_ats;  // how many now?
1724   _max_alias_types = grow_ats;
1725   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1726   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1727   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1728   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
1729 }
1730 
1731 
1732 //--------------------------------find_alias_type------------------------------
1733 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1734   if (_AliasLevel == 0)
1735     return alias_type(AliasIdxBot);
1736 
1737   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1738   if (ace->_adr_type == adr_type) {
1739     return alias_type(ace->_index);
1740   }
1741 
1742   // Handle special cases.
1743   if (adr_type == NULL)             return alias_type(AliasIdxTop);
1744   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
1745 
1746   // Do it the slow way.
1747   const TypePtr* flat = flatten_alias_type(adr_type);
1748 
1749 #ifdef ASSERT
1750   {
1751     ResourceMark rm;
1752     assert(flat == flatten_alias_type(flat), "not idempotent: adr_type = %s; flat = %s => %s",
1753            Type::str(adr_type), Type::str(flat), Type::str(flatten_alias_type(flat)));
1754     assert(flat != TypePtr::BOTTOM, "cannot alias-analyze an untyped ptr: adr_type = %s",
1755            Type::str(adr_type));
1756     if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1757       const TypeOopPtr* foop = flat->is_oopptr();
1758       // Scalarizable allocations have exact klass always.
1759       bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1760       const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1761       assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type: foop = %s; xoop = %s",
1762              Type::str(foop), Type::str(xoop));
1763     }
1764   }
1765 #endif
1766 
1767   int idx = AliasIdxTop;
1768   for (int i = 0; i < num_alias_types(); i++) {
1769     if (alias_type(i)->adr_type() == flat) {
1770       idx = i;
1771       break;
1772     }
1773   }
1774 
1775   if (idx == AliasIdxTop) {
1776     if (no_create)  return NULL;
1777     // Grow the array if necessary.
1778     if (_num_alias_types == _max_alias_types)  grow_alias_types();
1779     // Add a new alias type.
1780     idx = _num_alias_types++;
1781     _alias_types[idx]->Init(idx, flat);
1782     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
1783     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
1784     if (flat->isa_instptr()) {
1785       if (flat->offset() == java_lang_Class::klass_offset_in_bytes()
1786           && flat->is_instptr()->klass() == env()->Class_klass())
1787         alias_type(idx)->set_rewritable(false);
1788     }
1789     if (flat->isa_aryptr()) {
1790 #ifdef ASSERT
1791       const int header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1792       // (T_BYTE has the weakest alignment and size restrictions...)
1793       assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
1794 #endif
1795       if (flat->offset() == TypePtr::OffsetBot) {
1796         alias_type(idx)->set_element(flat->is_aryptr()->elem());
1797       }
1798     }
1799     if (flat->isa_klassptr()) {
1800       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1801         alias_type(idx)->set_rewritable(false);
1802       if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
1803         alias_type(idx)->set_rewritable(false);
1804       if (flat->offset() == in_bytes(Klass::access_flags_offset()))
1805         alias_type(idx)->set_rewritable(false);
1806       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1807         alias_type(idx)->set_rewritable(false);
1808     }
1809     // %%% (We would like to finalize JavaThread::threadObj_offset(),
1810     // but the base pointer type is not distinctive enough to identify
1811     // references into JavaThread.)
1812 
1813     // Check for final fields.
1814     const TypeInstPtr* tinst = flat->isa_instptr();
1815     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1816       ciField* field;
1817       if (tinst->const_oop() != NULL &&
1818           tinst->klass() == ciEnv::current()->Class_klass() &&
1819           tinst->offset() >= (tinst->klass()->as_instance_klass()->size_helper() * wordSize)) {
1820         // static field
1821         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1822         field = k->get_field_by_offset(tinst->offset(), true);
1823       } else {
1824         ciInstanceKlass *k = tinst->klass()->as_instance_klass();
1825         field = k->get_field_by_offset(tinst->offset(), false);
1826       }
1827       assert(field == NULL ||
1828              original_field == NULL ||
1829              (field->holder() == original_field->holder() &&
1830               field->offset() == original_field->offset() &&
1831               field->is_static() == original_field->is_static()), "wrong field?");
1832       // Set field() and is_rewritable() attributes.
1833       if (field != NULL)  alias_type(idx)->set_field(field);
1834     }
1835   }
1836 
1837   // Fill the cache for next time.
1838   ace->_adr_type = adr_type;
1839   ace->_index    = idx;
1840   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
1841 
1842   // Might as well try to fill the cache for the flattened version, too.
1843   AliasCacheEntry* face = probe_alias_cache(flat);
1844   if (face->_adr_type == NULL) {
1845     face->_adr_type = flat;
1846     face->_index    = idx;
1847     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1848   }
1849 
1850   return alias_type(idx);
1851 }
1852 
1853 
1854 Compile::AliasType* Compile::alias_type(ciField* field) {
1855   const TypeOopPtr* t;
1856   if (field->is_static())
1857     t = TypeInstPtr::make(field->holder()->java_mirror());
1858   else
1859     t = TypeOopPtr::make_from_klass_raw(field->holder());
1860   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1861   assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
1862   return atp;
1863 }
1864 
1865 
1866 //------------------------------have_alias_type--------------------------------
1867 bool Compile::have_alias_type(const TypePtr* adr_type) {
1868   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1869   if (ace->_adr_type == adr_type) {
1870     return true;
1871   }
1872 
1873   // Handle special cases.
1874   if (adr_type == NULL)             return true;
1875   if (adr_type == TypePtr::BOTTOM)  return true;
1876 
1877   return find_alias_type(adr_type, true, NULL) != NULL;
1878 }
1879 
1880 //-----------------------------must_alias--------------------------------------
1881 // True if all values of the given address type are in the given alias category.
1882 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1883   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1884   if (adr_type == NULL)                 return true;  // NULL serves as TypePtr::TOP
1885   if (alias_idx == AliasIdxTop)         return false; // the empty category
1886   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1887 
1888   // the only remaining possible overlap is identity
1889   int adr_idx = get_alias_index(adr_type);
1890   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1891   assert(adr_idx == alias_idx ||
1892          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1893           && adr_type                       != TypeOopPtr::BOTTOM),
1894          "should not be testing for overlap with an unsafe pointer");
1895   return adr_idx == alias_idx;
1896 }
1897 
1898 //------------------------------can_alias--------------------------------------
1899 // True if any values of the given address type are in the given alias category.
1900 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1901   if (alias_idx == AliasIdxTop)         return false; // the empty category
1902   if (adr_type == NULL)                 return false; // NULL serves as TypePtr::TOP
1903   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1904   if (adr_type->base() == Type::AnyPtr) return true;  // TypePtr::BOTTOM or its twins
1905 
1906   // the only remaining possible overlap is identity
1907   int adr_idx = get_alias_index(adr_type);
1908   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1909   return adr_idx == alias_idx;
1910 }
1911 
1912 
1913 
1914 //---------------------------pop_warm_call-------------------------------------
1915 WarmCallInfo* Compile::pop_warm_call() {
1916   WarmCallInfo* wci = _warm_calls;
1917   if (wci != NULL)  _warm_calls = wci->remove_from(wci);
1918   return wci;
1919 }
1920 
1921 //----------------------------Inline_Warm--------------------------------------
1922 int Compile::Inline_Warm() {
1923   // If there is room, try to inline some more warm call sites.
1924   // %%% Do a graph index compaction pass when we think we're out of space?
1925   if (!InlineWarmCalls)  return 0;
1926 
1927   int calls_made_hot = 0;
1928   int room_to_grow   = NodeCountInliningCutoff - unique();
1929   int amount_to_grow = MIN2(room_to_grow, (int)NodeCountInliningStep);
1930   int amount_grown   = 0;
1931   WarmCallInfo* call;
1932   while (amount_to_grow > 0 && (call = pop_warm_call()) != NULL) {
1933     int est_size = (int)call->size();
1934     if (est_size > (room_to_grow - amount_grown)) {
1935       // This one won't fit anyway.  Get rid of it.
1936       call->make_cold();
1937       continue;
1938     }
1939     call->make_hot();
1940     calls_made_hot++;
1941     amount_grown   += est_size;
1942     amount_to_grow -= est_size;
1943   }
1944 
1945   if (calls_made_hot > 0)  set_major_progress();
1946   return calls_made_hot;
1947 }
1948 
1949 
1950 //----------------------------Finish_Warm--------------------------------------
1951 void Compile::Finish_Warm() {
1952   if (!InlineWarmCalls)  return;
1953   if (failing())  return;
1954   if (warm_calls() == NULL)  return;
1955 
1956   // Clean up loose ends, if we are out of space for inlining.
1957   WarmCallInfo* call;
1958   while ((call = pop_warm_call()) != NULL) {
1959     call->make_cold();
1960   }
1961 }
1962 
1963 //---------------------cleanup_loop_predicates-----------------------
1964 // Remove the opaque nodes that protect the predicates so that all unused
1965 // checks and uncommon_traps will be eliminated from the ideal graph
1966 void Compile::cleanup_loop_predicates(PhaseIterGVN &igvn) {
1967   if (predicate_count()==0) return;
1968   for (int i = predicate_count(); i > 0; i--) {
1969     Node * n = predicate_opaque1_node(i-1);
1970     assert(n->Opcode() == Op_Opaque1, "must be");
1971     igvn.replace_node(n, n->in(1));
1972   }
1973   assert(predicate_count()==0, "should be clean!");
1974 }
1975 
1976 void Compile::add_range_check_cast(Node* n) {
1977   assert(n->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1978   assert(!_range_check_casts->contains(n), "duplicate entry in range check casts");
1979   _range_check_casts->append(n);
1980 }
1981 
1982 // Remove all range check dependent CastIINodes.
1983 void Compile::remove_range_check_casts(PhaseIterGVN &igvn) {
1984   for (int i = range_check_cast_count(); i > 0; i--) {
1985     Node* cast = range_check_cast_node(i-1);
1986     assert(cast->isa_CastII()->has_range_check(), "CastII should have range check dependency");
1987     igvn.replace_node(cast, cast->in(1));
1988   }
1989   assert(range_check_cast_count() == 0, "should be empty");
1990 }
1991 
1992 void Compile::add_opaque4_node(Node* n) {
1993   assert(n->Opcode() == Op_Opaque4, "Opaque4 only");
1994   assert(!_opaque4_nodes->contains(n), "duplicate entry in Opaque4 list");
1995   _opaque4_nodes->append(n);
1996 }
1997 
1998 // Remove all Opaque4 nodes.
1999 void Compile::remove_opaque4_nodes(PhaseIterGVN &igvn) {
2000   for (int i = opaque4_count(); i > 0; i--) {
2001     Node* opaq = opaque4_node(i-1);
2002     assert(opaq->Opcode() == Op_Opaque4, "Opaque4 only");
2003     igvn.replace_node(opaq, opaq->in(2));
2004   }
2005   assert(opaque4_count() == 0, "should be empty");
2006 }
2007 
2008 // StringOpts and late inlining of string methods
2009 void Compile::inline_string_calls(bool parse_time) {
2010   {
2011     // remove useless nodes to make the usage analysis simpler
2012     ResourceMark rm;
2013     PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2014   }
2015 
2016   {
2017     ResourceMark rm;
2018     print_method(PHASE_BEFORE_STRINGOPTS, 3);
2019     PhaseStringOpts pso(initial_gvn(), for_igvn());
2020     print_method(PHASE_AFTER_STRINGOPTS, 3);
2021   }
2022 
2023   // now inline anything that we skipped the first time around
2024   if (!parse_time) {
2025     _late_inlines_pos = _late_inlines.length();
2026   }
2027 
2028   while (_string_late_inlines.length() > 0) {
2029     CallGenerator* cg = _string_late_inlines.pop();
2030     cg->do_late_inline();
2031     if (failing())  return;
2032   }
2033   _string_late_inlines.trunc_to(0);
2034 }
2035 
2036 // Late inlining of boxing methods
2037 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
2038   if (_boxing_late_inlines.length() > 0) {
2039     assert(has_boxed_value(), "inconsistent");
2040 
2041     PhaseGVN* gvn = initial_gvn();
2042     set_inlining_incrementally(true);
2043 
2044     assert( igvn._worklist.size() == 0, "should be done with igvn" );
2045     for_igvn()->clear();
2046     gvn->replace_with(&igvn);
2047 
2048     _late_inlines_pos = _late_inlines.length();
2049 
2050     while (_boxing_late_inlines.length() > 0) {
2051       CallGenerator* cg = _boxing_late_inlines.pop();
2052       cg->do_late_inline();
2053       if (failing())  return;
2054     }
2055     _boxing_late_inlines.trunc_to(0);
2056 
2057     inline_incrementally_cleanup(igvn);
2058 
2059     set_inlining_incrementally(false);
2060   }
2061 }
2062 
2063 bool Compile::inline_incrementally_one() {
2064   assert(IncrementalInline, "incremental inlining should be on");
2065 
2066   TracePhase tp("incrementalInline_inline", &timers[_t_incrInline_inline]);
2067   set_inlining_progress(false);
2068   set_do_cleanup(false);
2069   int i = 0;
2070   for (; i <_late_inlines.length() && !inlining_progress(); i++) {
2071     CallGenerator* cg = _late_inlines.at(i);
2072     _late_inlines_pos = i+1;
2073     cg->do_late_inline();
2074     if (failing())  return false;
2075   }
2076   int j = 0;
2077   for (; i < _late_inlines.length(); i++, j++) {
2078     _late_inlines.at_put(j, _late_inlines.at(i));
2079   }
2080   _late_inlines.trunc_to(j);
2081   assert(inlining_progress() || _late_inlines.length() == 0, "");
2082 
2083   bool needs_cleanup = do_cleanup() || over_inlining_cutoff();
2084 
2085   set_inlining_progress(false);
2086   set_do_cleanup(false);
2087   return (_late_inlines.length() > 0) && !needs_cleanup;
2088 }
2089 
2090 void Compile::inline_incrementally_cleanup(PhaseIterGVN& igvn) {
2091   {
2092     TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2093     ResourceMark rm;
2094     PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2095   }
2096   {
2097     TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2098     igvn = PhaseIterGVN(initial_gvn());
2099     igvn.optimize();
2100   }
2101 }
2102 
2103 // Perform incremental inlining until bound on number of live nodes is reached
2104 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
2105   TracePhase tp("incrementalInline", &timers[_t_incrInline]);
2106 
2107   set_inlining_incrementally(true);
2108   uint low_live_nodes = 0;
2109 
2110   while (_late_inlines.length() > 0) {
2111     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2112       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
2113         TracePhase tp("incrementalInline_ideal", &timers[_t_incrInline_ideal]);
2114         // PhaseIdealLoop is expensive so we only try it once we are
2115         // out of live nodes and we only try it again if the previous
2116         // helped got the number of nodes down significantly
2117         PhaseIdealLoop::optimize(igvn, LoopOptsNone);
2118         if (failing())  return;
2119         low_live_nodes = live_nodes();
2120         _major_progress = true;
2121       }
2122 
2123       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2124         break; // finish
2125       }
2126     }
2127 
2128     for_igvn()->clear();
2129     initial_gvn()->replace_with(&igvn);
2130 
2131     while (inline_incrementally_one()) {
2132       assert(!failing(), "inconsistent");
2133     }
2134 
2135     if (failing())  return;
2136 
2137     inline_incrementally_cleanup(igvn);
2138 
2139     print_method(PHASE_INCREMENTAL_INLINE_STEP, 3);
2140 
2141 
2142     if (failing())  return;
2143   }
2144   assert( igvn._worklist.size() == 0, "should be done with igvn" );
2145 
2146   if (_string_late_inlines.length() > 0) {
2147     assert(has_stringbuilder(), "inconsistent");
2148     for_igvn()->clear();
2149     initial_gvn()->replace_with(&igvn);
2150 
2151     inline_string_calls(false);
2152 
2153     if (failing())  return;
2154 
2155     inline_incrementally_cleanup(igvn);
2156   }
2157 
2158   set_inlining_incrementally(false);
2159 }
2160 
2161 
2162 bool Compile::optimize_loops(PhaseIterGVN& igvn, LoopOptsMode mode) {
2163   if(_loop_opts_cnt > 0) {
2164     debug_only( int cnt = 0; );
2165     while(major_progress() && (_loop_opts_cnt > 0)) {
2166       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2167       assert( cnt++ < 40, "infinite cycle in loop optimization" );
2168       PhaseIdealLoop::optimize(igvn, mode);
2169       _loop_opts_cnt--;
2170       if (failing())  return false;
2171       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
2172     }
2173   }
2174   return true;
2175 }
2176 
2177 // Remove edges from "root" to each SafePoint at a backward branch.
2178 // They were inserted during parsing (see add_safepoint()) to make
2179 // infinite loops without calls or exceptions visible to root, i.e.,
2180 // useful.
2181 void Compile::remove_root_to_sfpts_edges(PhaseIterGVN& igvn) {
2182   Node *r = root();
2183   if (r != NULL) {
2184     for (uint i = r->req(); i < r->len(); ++i) {
2185       Node *n = r->in(i);
2186       if (n != NULL && n->is_SafePoint()) {
2187         r->rm_prec(i);
2188         if (n->outcnt() == 0) {
2189           igvn.remove_dead_node(n);
2190         }
2191         --i;
2192       }
2193     }
2194   }
2195 }
2196 
2197 //------------------------------Optimize---------------------------------------
2198 // Given a graph, optimize it.
2199 void Compile::Optimize() {
2200   TracePhase tp("optimizer", &timers[_t_optimizer]);
2201 
2202 #ifndef PRODUCT
2203   if (_directive->BreakAtCompileOption) {
2204     BREAKPOINT;
2205   }
2206 
2207 #endif
2208 
2209 #ifdef ASSERT
2210   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2211   bs->verify_gc_barriers(this, BarrierSetC2::BeforeOptimize);
2212 #endif
2213 
2214   ResourceMark rm;
2215 
2216   print_inlining_reinit();
2217 
2218   NOT_PRODUCT( verify_graph_edges(); )
2219 
2220   print_method(PHASE_AFTER_PARSING);
2221 
2222  {
2223   // Iterative Global Value Numbering, including ideal transforms
2224   // Initialize IterGVN with types and values from parse-time GVN
2225   PhaseIterGVN igvn(initial_gvn());
2226 #ifdef ASSERT
2227   _modified_nodes = new (comp_arena()) Unique_Node_List(comp_arena());
2228 #endif
2229   {
2230     TracePhase tp("iterGVN", &timers[_t_iterGVN]);
2231     igvn.optimize();
2232   }
2233 
2234   if (failing())  return;
2235 
2236   print_method(PHASE_ITER_GVN1, 2);
2237 
2238   inline_incrementally(igvn);
2239 
2240   print_method(PHASE_INCREMENTAL_INLINE, 2);
2241 
2242   if (failing())  return;
2243 
2244   if (eliminate_boxing()) {
2245     // Inline valueOf() methods now.
2246     inline_boxing_calls(igvn);
2247 
2248     if (AlwaysIncrementalInline) {
2249       inline_incrementally(igvn);
2250     }
2251     if (failing())  return;
2252 
2253     print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
2254   }
2255 
2256   // Now that all inlining is over, cut edge from root to loop
2257   // safepoints
2258   remove_root_to_sfpts_edges(igvn);
2259 
2260   // Remove the speculative part of types and clean up the graph from
2261   // the extra CastPP nodes whose only purpose is to carry them. Do
2262   // that early so that optimizations are not disrupted by the extra
2263   // CastPP nodes.
2264   remove_speculative_types(igvn);
2265 
2266   // No more new expensive nodes will be added to the list from here
2267   // so keep only the actual candidates for optimizations.
2268   cleanup_expensive_nodes(igvn);
2269 
2270   if (has_vbox_nodes()) {
2271     TracePhase tp("expandVectorBoxes", &timers[_t_expandVectorBoxes]);
2272 
2273     set_inlining_incrementally(true); // FIXME another way to signal GraphKit it's post-parsing phase?
2274 
2275     for_igvn()->clear();
2276     initial_gvn()->replace_with(&igvn);
2277 
2278     expand_vunbox_nodes();
2279     scalarize_vbox_nodes();
2280 
2281     inline_vector_reboxing_calls();
2282 
2283     if (failing())  return;
2284     {
2285       ResourceMark rm;
2286       PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2287     }
2288     igvn = PhaseIterGVN(initial_gvn());
2289     igvn.optimize();
2290 
2291     print_method(PHASE_ITER_GVN_BEFORE_EA, 2);
2292 
2293     if (failing())  return;
2294 
2295     ////////////////////////////////////////////////////
2296 
2297     for_igvn()->clear();
2298     initial_gvn()->replace_with(&igvn);
2299 
2300     expand_vbox_nodes();
2301     eliminate_vbox_alloc_nodes();
2302 
2303     if (failing())  return;
2304     {
2305       ResourceMark rm;
2306       PhaseRemoveUseless pru(initial_gvn(), for_igvn());
2307     }
2308     igvn = PhaseIterGVN(initial_gvn());
2309     igvn.optimize();
2310     if (failing())  return;
2311 
2312     print_method(PHASE_ITER_GVN_BEFORE_EA, 2);
2313 
2314     set_inlining_incrementally(false); // FIXME another way to signal GraphKit it's post-parsing phase?
2315   }
2316 
2317   if (!failing() && RenumberLiveNodes && live_nodes() + NodeLimitFudgeFactor < unique()) {
2318     Compile::TracePhase tp("", &timers[_t_renumberLive]);
2319     initial_gvn()->replace_with(&igvn);
2320     for_igvn()->clear();
2321     Unique_Node_List new_worklist(C->comp_arena());
2322     {
2323       ResourceMark rm;
2324       PhaseRenumberLive prl = PhaseRenumberLive(initial_gvn(), for_igvn(), &new_worklist);
2325     }
2326     set_for_igvn(&new_worklist);
2327     igvn = PhaseIterGVN(initial_gvn());
2328     igvn.optimize();
2329   }
2330 
2331   // FIXME for_igvn() is corrupted from here: new_worklist which is set_for_ignv() was allocated on stack.
2332 
2333   // Perform escape analysis
2334   if (_do_escape_analysis && ConnectionGraph::has_candidates(this)) {
2335     if (has_loops()) {
2336       // Cleanup graph (remove dead nodes).
2337       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2338       PhaseIdealLoop::optimize(igvn, LoopOptsNone);
2339       if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
2340       if (failing())  return;
2341     }
2342     ConnectionGraph::do_analysis(this, &igvn);
2343 
2344     if (failing())  return;
2345 
2346     // Optimize out fields loads from scalar replaceable allocations.
2347     igvn.optimize();
2348     print_method(PHASE_ITER_GVN_AFTER_EA, 2);
2349 
2350     if (failing())  return;
2351 
2352     if (congraph() != NULL && macro_count() > 0) {
2353       TracePhase tp("macroEliminate", &timers[_t_macroEliminate]);
2354       PhaseMacroExpand mexp(igvn);
2355       mexp.eliminate_macro_nodes();
2356       igvn.set_delay_transform(false);
2357 
2358       igvn.optimize();
2359       print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
2360 
2361       if (failing())  return;
2362     }
2363   }
2364 
2365   // Loop transforms on the ideal graph.  Range Check Elimination,
2366   // peeling, unrolling, etc.
2367 
2368   // Set loop opts counter
2369   if((_loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
2370     {
2371       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2372       PhaseIdealLoop::optimize(igvn, LoopOptsDefault);
2373       _loop_opts_cnt--;
2374       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
2375       if (failing())  return;
2376     }
2377     // Loop opts pass if partial peeling occurred in previous pass
2378     if(PartialPeelLoop && major_progress() && (_loop_opts_cnt > 0)) {
2379       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2380       PhaseIdealLoop::optimize(igvn, LoopOptsSkipSplitIf);
2381       _loop_opts_cnt--;
2382       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
2383       if (failing())  return;
2384     }
2385     // Loop opts pass for loop-unrolling before CCP
2386     if(major_progress() && (_loop_opts_cnt > 0)) {
2387       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2388       PhaseIdealLoop::optimize(igvn, LoopOptsSkipSplitIf);
2389       _loop_opts_cnt--;
2390       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
2391     }
2392     if (!failing()) {
2393       // Verify that last round of loop opts produced a valid graph
2394       TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2395       PhaseIdealLoop::verify(igvn);
2396     }
2397   }
2398   if (failing())  return;
2399 
2400   // Conditional Constant Propagation;
2401   PhaseCCP ccp( &igvn );
2402   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
2403   {
2404     TracePhase tp("ccp", &timers[_t_ccp]);
2405     ccp.do_transform();
2406   }
2407   print_method(PHASE_CPP1, 2);
2408 
2409   assert( true, "Break here to ccp.dump_old2new_map()");
2410 
2411   // Iterative Global Value Numbering, including ideal transforms
2412   {
2413     TracePhase tp("iterGVN2", &timers[_t_iterGVN2]);
2414     igvn = ccp;
2415     igvn.optimize();
2416   }
2417 
2418   print_method(PHASE_ITER_GVN2, 2);
2419 
2420   if (failing())  return;
2421 
2422   // Loop transforms on the ideal graph.  Range Check Elimination,
2423   // peeling, unrolling, etc.
2424   if (!optimize_loops(igvn, LoopOptsDefault)) {
2425     return;
2426   }
2427 
2428 #if INCLUDE_ZGC
2429   if (UseZGC) {
2430     ZBarrierSetC2::find_dominating_barriers(igvn);
2431   }
2432 #endif
2433 
2434   if (failing())  return;
2435 
2436   // Ensure that major progress is now clear
2437   C->clear_major_progress();
2438 
2439   {
2440     // Verify that all previous optimizations produced a valid graph
2441     // at least to this point, even if no loop optimizations were done.
2442     TracePhase tp("idealLoopVerify", &timers[_t_idealLoopVerify]);
2443     PhaseIdealLoop::verify(igvn);
2444   }
2445 
2446   if (range_check_cast_count() > 0) {
2447     // No more loop optimizations. Remove all range check dependent CastIINodes.
2448     C->remove_range_check_casts(igvn);
2449     igvn.optimize();
2450   }
2451 
2452 #ifdef ASSERT
2453   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2454   bs->verify_gc_barriers(this, BarrierSetC2::BeforeExpand);
2455 #endif
2456 
2457   {
2458     TracePhase tp("macroExpand", &timers[_t_macroExpand]);
2459     PhaseMacroExpand  mex(igvn);
2460     print_method(PHASE_BEFORE_MACRO_EXPANSION, 2);
2461     if (mex.expand_macro_nodes()) {
2462       assert(failing(), "must bail out w/ explicit message");
2463       return;
2464     }
2465   }
2466 
2467   {
2468     TracePhase tp("barrierExpand", &timers[_t_barrierExpand]);
2469     print_method(PHASE_BEFORE_BARRIER_EXPAND, 2);
2470     BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2471     if (bs->expand_barriers(this, igvn)) {
2472       assert(failing(), "must bail out w/ explicit message");
2473       return;
2474     }
2475   }
2476 
2477   if (opaque4_count() > 0) {
2478     C->remove_opaque4_nodes(igvn);
2479     igvn.optimize();
2480   }
2481 
2482   DEBUG_ONLY( _modified_nodes = NULL; )
2483  } // (End scope of igvn; run destructor if necessary for asserts.)
2484 
2485  process_print_inlining();
2486  // A method with only infinite loops has no edges entering loops from root
2487  {
2488    TracePhase tp("graphReshape", &timers[_t_graphReshaping]);
2489    if (final_graph_reshaping()) {
2490      assert(failing(), "must bail out w/ explicit message");
2491      return;
2492    }
2493  }
2494 
2495  print_method(PHASE_OPTIMIZE_FINISHED, 2);
2496 }
2497 
2498 void Compile::print_method(CompilerPhaseType cpt, Node* n, int level) {
2499   ResourceMark rm;
2500   stringStream ss;
2501   ss.print_raw(CompilerPhaseTypeHelper::to_string(cpt));
2502   if (n != NULL) {
2503 #ifndef PRODUCT
2504     ss.print(": %s %d", n->Name(), n->_idx);
2505 #else
2506     ss.print(": %d %d", n->Opcode(), n->_idx);
2507 #endif // PRODUCT
2508   } else {
2509     ss.print_raw(": NULL");
2510   }
2511   C->print_method(cpt, ss.as_string(), level);
2512 }
2513 
2514 void Compile::scalarize_vbox_nodes() {
2515   int macro_idx = C->macro_count() - 1;
2516   while(macro_idx >= 0) {
2517     Node * n = C->macro_node(macro_idx);
2518     assert(n->is_macro(), "only macro nodes expected here");
2519     if (n->Opcode() == Op_VectorBox) {
2520       VectorBoxNode* vbox = static_cast<VectorBoxNode*>(n);
2521       scalarize_vbox_node(vbox);
2522       if (failing())  return;
2523       print_method(PHASE_SCALARIZE_VBOX, vbox);
2524     }
2525     if (C->failing())  return;
2526     macro_idx = MIN2(macro_idx - 1, C->macro_count() - 1);
2527   }
2528 }
2529 
2530 void Compile::expand_vbox_nodes() {
2531   int macro_idx = C->macro_count() - 1;
2532   while(macro_idx >= 0) {
2533     Node * n = C->macro_node(macro_idx);
2534     assert(n->is_macro(), "only macro nodes expected here");
2535     if (n->Opcode() == Op_VectorBox) {
2536       VectorBoxNode* vbox = static_cast<VectorBoxNode*>(n);
2537       expand_vbox_node(vbox);
2538       if (failing())  return;
2539       print_method(PHASE_EXPAND_VBOX, vbox);
2540     }
2541     if (C->failing())  return;
2542     macro_idx = MIN2(macro_idx - 1, C->macro_count() - 1);
2543   }
2544 }
2545 
2546 void Compile::expand_vunbox_nodes() {
2547   int macro_idx = C->macro_count() - 1;
2548   while(macro_idx >= 0) {
2549     Node * n = C->macro_node(macro_idx);
2550     assert(n->is_macro(), "only macro nodes expected here");
2551     if (n->Opcode() == Op_VectorUnbox) {
2552       VectorUnboxNode* vec_unbox = static_cast<VectorUnboxNode*>(n);
2553       expand_vunbox_node(vec_unbox);
2554       if (failing())  return;
2555       print_method(PHASE_EXPAND_VUNBOX, vec_unbox);
2556     }
2557     if (C->failing())  return;
2558     macro_idx = MIN2(macro_idx - 1, C->macro_count() - 1);
2559   }
2560 }
2561 
2562 void Compile::eliminate_vbox_alloc_nodes() {
2563   int macro_idx = C->macro_count() - 1;
2564   while(macro_idx >= 0) {
2565     Node * n = C->macro_node(macro_idx);
2566     assert(n->is_macro(), "only macro nodes expected here");
2567     if (n->Opcode() == Op_VectorBoxAllocate) {
2568       VectorBoxAllocateNode* vbox_alloc = static_cast<VectorBoxAllocateNode*>(n);
2569       eliminate_vbox_alloc_node(vbox_alloc);
2570       if (failing())  return;
2571       print_method(PHASE_ELIMINATE_VBOX_ALLOC, vbox_alloc);
2572     }
2573     if (C->failing())  return;
2574     macro_idx = MIN2(macro_idx - 1, C->macro_count() - 1);
2575   }
2576 }
2577 
2578 void Compile::inline_vector_reboxing_calls() {
2579   if (_vector_reboxing_late_inlines.length() > 0) {
2580     PhaseGVN* gvn = initial_gvn();
2581 
2582     _late_inlines_pos = _late_inlines.length();
2583     while (_vector_reboxing_late_inlines.length() > 0) {
2584       CallGenerator* cg = _vector_reboxing_late_inlines.pop();
2585       cg->do_late_inline();
2586       if (failing())  return;
2587       print_method(PHASE_INLINE_VECTOR_REBOX, cg->call_node());
2588     }
2589     _vector_reboxing_late_inlines.trunc_to(0);
2590   }
2591 }
2592 
2593 bool Compile::has_vbox_nodes() {
2594   if (_vector_reboxing_late_inlines.length() > 0) {
2595     return true;
2596   }
2597   for (int macro_idx = C->macro_count() - 1; macro_idx >= 0; macro_idx--) {
2598     Node * n = C->macro_node(macro_idx);
2599     assert(n->is_macro(), "only macro nodes expected here");
2600     if (n->Opcode() == Op_VectorUnbox || n->Opcode() == Op_VectorBox || n->Opcode() == Op_VectorBoxAllocate) {
2601       return true;
2602     }
2603   }
2604   return false;
2605 }
2606 
2607 static JVMState* clone_jvms(Compile* C, SafePointNode* sfpt) {
2608   JVMState* new_jvms = sfpt->jvms()->clone_shallow(C);
2609   uint size = sfpt->req();
2610   SafePointNode* map = new SafePointNode(size, new_jvms);
2611   for (uint i = 0; i < size; i++) {
2612     map->init_req(i, sfpt->in(i));
2613   }
2614   // Make sure the state is a MergeMem for parsing.
2615   // FIXME not needed?
2616 //  if (!map->in(TypeFunc::Memory)->is_MergeMem()) {
2617 //    Node* mem = MergeMemNode::make(map->in(TypeFunc::Memory));
2618 //    gvn.set_type_bottom(mem);
2619 //    map->set_req(TypeFunc::Memory, mem);
2620 //  }
2621   new_jvms->set_map(map);
2622   return new_jvms;
2623 }
2624 
2625 void Compile::scalarize_vbox_node(VectorBoxNode* vec_box) {
2626   Node* vec_value = vec_box->in(VectorBoxNode::Value);
2627   PhaseGVN& gvn = *initial_gvn();
2628 
2629   // Process merged VBAs
2630 
2631   Unique_Node_List calls(C->comp_arena());
2632   for (DUIterator_Fast imax, i = vec_box->fast_outs(imax); i < imax; i++) {
2633     Node* use = vec_box->fast_out(i);
2634     if (use->is_CallJava()) {
2635       CallJavaNode* call = use->as_CallJava();
2636       if (call->has_non_debug_use(vec_box) && vec_box->in(VectorBoxNode::Box)->is_Phi()) {
2637         calls.push(call);
2638       }
2639     }
2640   }
2641 
2642   while (VectorAPIAggressiveReboxing && calls.size() > 0) {
2643     CallJavaNode* call = calls.pop()->as_CallJava();
2644     // Attach new VBA to the call and use it instead of Phi (VBA ... VBA).
2645 
2646     JVMState* jvms = clone_jvms(C, call);
2647     GraphKit kit(jvms);
2648     PhaseGVN& gvn = kit.gvn();
2649 
2650     // Adjust JVMS from post-call to pre-call state: put args on stack
2651     uint nargs = call->method()->arg_size();
2652     kit.ensure_stack(kit.sp() + nargs);
2653     for (uint i = TypeFunc::Parms; i < call->tf()->domain()->cnt(); i++) {
2654       kit.push(call->in(i));
2655     }
2656     jvms = kit.sync_jvms();
2657 
2658     Node* new_vbox = NULL;
2659     {
2660       PreserveReexecuteState prs(&kit);
2661 
2662       kit.jvms()->set_should_reexecute(true);
2663 
2664       const TypeInstPtr* vbox_type = vec_box->box_type();
2665       const TypeVect* vect_type = vec_box->vec_type();
2666       Node* vect = vec_box->in(VectorBoxNode::Value);
2667 
2668       VectorBoxAllocateNode* alloc = new VectorBoxAllocateNode(C, vbox_type);
2669       kit.set_edges_for_java_call(alloc, /*must_throw=*/false, /*separate_io_proj=*/true);
2670       kit.make_slow_call_ex(alloc, env()->Throwable_klass(), /*separate_io_proj=*/true, /*deoptimize=*/true);
2671       kit.set_i_o(gvn.transform( new ProjNode(alloc, TypeFunc::I_O) ));
2672       kit.set_all_memory(gvn.transform( new ProjNode(alloc, TypeFunc::Memory) ));
2673       Node* ret = gvn.transform(new ProjNode(alloc, TypeFunc::Parms));
2674 
2675       new_vbox = gvn.transform(new VectorBoxNode(C, ret, vect, vbox_type, vect_type));
2676 
2677       kit.replace_in_map(vec_box, new_vbox);
2678     }
2679 
2680     kit.dec_sp(nargs);
2681     jvms = kit.sync_jvms();
2682 
2683     bool found = false;
2684     int cnt = _vector_reboxing_late_inlines.length();
2685     for (int i = 0; i < cnt; i++) {
2686       CallGenerator* cg = _vector_reboxing_late_inlines.at(i);
2687       if (cg->call_node() == call) {
2688         ciMethod* m = cg->method();
2689         _vector_reboxing_late_inlines.remove(cg); // remove_at(i);
2690         CallGenerator* new_cg = CallGenerator::for_vector_reboxing_late_inline(
2691             m,
2692             CallGenerator::for_inline(m, m->interpreter_invocation_count()));
2693 
2694         JVMState* new_jvms = new_cg->generate(jvms);
2695 
2696         Node* new_res = kit.top();
2697         if (m->return_type()->basic_type() != T_VOID) {
2698           new_res = new_cg->call_node()->proj_out(TypeFunc::Parms);
2699         }
2700         kit.replace_call(call, new_res, /*do_replaced_nodes=*/true);
2701 
2702         found = true;
2703         break;
2704       }
2705     }
2706 
2707     if (!found) {
2708       // FIXME does it cover all cases?
2709       CallJavaNode* new_call = call->clone()->as_CallJava();
2710       new_call->set_req(TypeFunc::Control  , kit.control());
2711       new_call->set_req(TypeFunc::I_O      , kit.i_o());
2712       new_call->set_req(TypeFunc::Memory   , kit.reset_memory());
2713       new_call->set_req(TypeFunc::FramePtr , kit.frameptr());
2714 
2715       new_call->replace_edge(vec_box, new_vbox);
2716       new_call = gvn.transform(new_call)->as_CallJava();
2717 
2718       C->gvn_replace_by(call, new_call);
2719     }
2720     call->disconnect_inputs(NULL, C);
2721   }
2722 
2723   // Process debug uses at safepoints
2724   Unique_Node_List safepoints(C->comp_arena());
2725 
2726   for (DUIterator_Fast imax, i = vec_box->fast_outs(imax); i < imax; i++) {
2727     Node* use = vec_box->fast_out(i);
2728     if (use->is_SafePoint()) {
2729       SafePointNode* sfpt = use->as_SafePoint();
2730       if (!sfpt->is_Call() || !sfpt->as_Call()->has_non_debug_use(vec_box)) {
2731         safepoints.push(sfpt);
2732       }
2733     }
2734   }
2735 
2736   while (safepoints.size() > 0) {
2737     SafePointNode* sfpt = safepoints.pop()->as_SafePoint();
2738 
2739     uint first_ind = (sfpt->req() - sfpt->jvms()->scloff());
2740     Node* sobj = new SafePointScalarObjectNode(vec_box->box_type(),
2741 #ifdef ASSERT
2742                                                NULL,
2743 #endif // ASSERT
2744                                                first_ind, /*n_fields=*/1);
2745     sobj->init_req(0, C->root());
2746     sfpt->add_req(vec_value);
2747 
2748     sobj = gvn.transform(sobj);
2749 
2750     JVMState *jvms = sfpt->jvms();
2751 
2752     jvms->set_endoff(sfpt->req());
2753     // Now make a pass over the debug information replacing any references
2754     // to the allocated object with "sobj"
2755     int start = jvms->debug_start();
2756     int end   = jvms->debug_end();
2757     sfpt->replace_edges_in_range(vec_box, sobj, start, end);
2758   }
2759 }
2760 
2761 void Compile::expand_vbox_node(VectorBoxNode* vec_box) {
2762   if (vec_box->outcnt() > 0) {
2763     Node* vbox = vec_box->in(VectorBoxNode::Box);
2764     Node* vect = vec_box->in(VectorBoxNode::Value);
2765     Node* result = expand_vbox_node_helper(vbox, vect, vec_box->box_type(), vec_box->vec_type());
2766     C->gvn_replace_by(vec_box, result);
2767   }
2768   C->remove_macro_node(vec_box);
2769 }
2770 
2771 Node* Compile::expand_vbox_node_helper(Node* vbox,
2772                                        Node* vect,
2773                                        const TypeInstPtr* box_type,
2774                                        const TypeVect* vect_type) {
2775   if (vbox->is_Phi() && vect->is_Phi()) {
2776     assert(vbox->as_Phi()->region() == vect->as_Phi()->region(), "");
2777     Node* new_phi = new PhiNode(vbox->as_Phi()->region(), box_type);
2778     for (uint i = 1; i < vbox->req(); i++) {
2779       Node* new_box = expand_vbox_node_helper(vbox->in(i), vect->in(i), box_type, vect_type);
2780       new_phi->set_req(i, new_box);
2781     }
2782     new_phi = initial_gvn()->transform(new_phi);
2783     return new_phi;
2784   } else if (vbox->is_Proj() && vbox->in(0)->Opcode() == Op_VectorBoxAllocate) {
2785     VectorBoxAllocateNode* vbox_alloc = static_cast<VectorBoxAllocateNode*>(vbox->in(0));
2786     return expand_vbox_alloc_node(vbox_alloc, vect, box_type, vect_type);
2787   } else {
2788     // TODO: ensure that expanded vbox is initialized with the same value (vect).
2789     return vbox; // already expanded
2790   }
2791 }
2792 
2793 Node* Compile::expand_vbox_alloc_node(VectorBoxAllocateNode* vbox_alloc,
2794                                       Node* value,
2795                                       const TypeInstPtr* box_type,
2796                                       const TypeVect* vect_type) {
2797   JVMState* jvms = clone_jvms(C, vbox_alloc);
2798   GraphKit kit(jvms);
2799   PhaseGVN& gvn = kit.gvn();
2800 
2801   ciInstanceKlass* box_klass = box_type->klass()->as_instance_klass();
2802   BasicType bt = vect_type->element_basic_type();
2803   int num_elem = vect_type->length();
2804 
2805   bool is_mask = box_klass->is_vectormask();
2806   //assert(!is_mask || vect_type->element_basic_type() == getMaskBasicType(bt), "consistent vector element type expected");
2807   if (is_mask && bt != T_BOOLEAN) {
2808     value = gvn.transform(new VectorStoreMaskNode(value, bt, num_elem));
2809     // Although type of mask depends on its definition, in terms of storage everything is stored in boolean array.
2810     bt = T_BOOLEAN;
2811     assert(value->as_Vector()->bottom_type()->is_vect()->element_basic_type() == bt,
2812            "must be consistent with mask representation");
2813   }
2814 
2815   // Generate the allocate for the Vector object.
2816   const TypeKlassPtr* klass_type = box_type->as_klass_type();
2817   Node* klass_node = kit.makecon(klass_type);
2818   Node* vec_obj = kit.new_instance(klass_node);
2819 
2820   // Generate array allocation for the field which holds the values.
2821   const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(bt));
2822   Node* arr = kit.new_array(kit.makecon(array_klass), kit.intcon(num_elem), 1);
2823 
2824   // FIXME convert both stores into initializing stores
2825 
2826   // Store the vector value into the array.
2827   Node* arr_adr = kit.array_element_address(arr, kit.intcon(0), bt);
2828   const TypePtr* arr_adr_type = arr_adr->bottom_type()->is_ptr();
2829   Node* arr_mem = kit.memory(arr_adr);
2830   Node* vstore = gvn.transform(StoreVectorNode::make(0,
2831                                                      kit.control(),
2832                                                      arr_mem,
2833                                                      arr_adr,
2834                                                      arr_adr_type,
2835                                                      value,
2836                                                      num_elem));
2837   kit.set_memory(vstore, arr_adr_type);
2838 
2839 
2840   // Store the allocated array into object.
2841   ciField* field = box_klass->get_field_by_name(ciSymbol::make(is_mask ? "bits" : "vec"),
2842                                                 ciSymbol::make(TypeArrayKlass::external_name(bt)),
2843                                                 false);
2844   Node* vec_field = kit.basic_plus_adr(vec_obj, field->offset_in_bytes());
2845   const TypePtr* vec_adr_type = vec_field->bottom_type()->is_ptr();
2846   Node* field_store = gvn.transform(kit.access_store_at(vec_obj,
2847                                                             vec_field,
2848                                                             vec_adr_type,
2849                                                             arr,
2850                                                             TypeOopPtr::make_from_klass(field->type()->as_klass()),
2851                                                             T_OBJECT,
2852                                                             IN_HEAP));
2853 
2854   kit.set_memory(field_store, vec_adr_type);
2855 
2856   kit.replace_call(vbox_alloc, vec_obj, true);
2857   C->remove_macro_node(vbox_alloc);
2858   return vec_obj;
2859 }
2860 
2861 void Compile::expand_vunbox_node(VectorUnboxNode* vec_unbox) {
2862   if (vec_unbox->outcnt() > 0) {
2863     GraphKit kit;
2864     PhaseGVN& gvn = kit.gvn();
2865 
2866     Node* obj = vec_unbox->obj();
2867     const TypeInstPtr* tinst = gvn.type(obj)->isa_instptr();
2868     ciInstanceKlass* from_kls = tinst->klass()->as_instance_klass();
2869     BasicType bt = vec_unbox->vect_type()->element_basic_type();
2870     BasicType masktype = bt;
2871 
2872     const char* field_name = "vec";
2873     if (from_kls->is_vectormask()) {
2874       field_name = "bits";
2875       bt = T_BOOLEAN;
2876     } else if (from_kls->is_vectorshuffle()) {
2877       field_name = "reorder";
2878       bt = T_BYTE;
2879     }
2880 
2881     ciField* field = from_kls->get_field_by_name(ciSymbol::make(field_name),
2882       ciSymbol::make(TypeArrayKlass::external_name(bt)), false);
2883 
2884     int offset = field->offset_in_bytes();
2885     Node* vec_adr = kit.basic_plus_adr(obj, offset);
2886 
2887     Node* mem = vec_unbox->mem();
2888     Node* ctrl = vec_unbox->in(0);
2889     Node* vec_field_ld = LoadNode::make(gvn,
2890                                         ctrl,
2891                                         mem,
2892                                         vec_adr,
2893                                         vec_adr->bottom_type()->is_ptr(),
2894                                         TypeOopPtr::make_from_klass(field->type()->as_klass()),
2895                                         T_OBJECT,
2896                                         MemNode::unordered);
2897     vec_field_ld = gvn.transform(vec_field_ld);
2898 
2899     Node* adr = kit.array_element_address(vec_field_ld, gvn.intcon(0), bt);
2900     const TypePtr* adr_type = adr->bottom_type()->is_ptr();
2901     int num_elem = vec_unbox->bottom_type()->is_vect()->length();
2902     Node* vec_val_load = LoadVectorNode::make(0,
2903                                               ctrl,
2904                                               mem,
2905                                               adr,
2906                                               adr_type,
2907                                               num_elem,
2908                                               bt);
2909     vec_val_load = gvn.transform(vec_val_load);
2910 
2911     if (from_kls->is_vectormask() && masktype != T_BOOLEAN) {
2912       assert(vec_unbox->bottom_type()->is_vect()->element_basic_type() == masktype, "expect mask type consistency");
2913       vec_val_load = gvn.transform(new VectorLoadMaskNode(vec_val_load, TypeVect::make(masktype, num_elem)));
2914     } else if (from_kls->is_vectorshuffle()) {
2915       assert(vec_unbox->bottom_type()->is_vect()->element_basic_type() == masktype, "expect shuffle type consistency");
2916       vec_val_load = gvn.transform(new VectorLoadShuffleNode(vec_val_load, TypeVect::make(masktype, num_elem)));
2917     }
2918 
2919     gvn.hash_delete(vec_unbox);
2920     vec_unbox->disconnect_inputs(NULL, C);
2921     C->gvn_replace_by(vec_unbox, vec_val_load);
2922   }
2923   C->remove_macro_node(vec_unbox);
2924 }
2925 
2926 void Compile::eliminate_vbox_alloc_node(VectorBoxAllocateNode* vbox_alloc) {
2927   JVMState* jvms = clone_jvms(C, vbox_alloc);
2928   GraphKit kit(jvms);
2929   // FIXME replace VBA with a safepoint. Otherwise, no safepoints left in tight loops.
2930   kit.replace_call(vbox_alloc, kit.top(), true);
2931   C->remove_macro_node(vbox_alloc);
2932 }
2933 
2934 //------------------------------Code_Gen---------------------------------------
2935 // Given a graph, generate code for it
2936 void Compile::Code_Gen() {
2937   if (failing()) {
2938     return;
2939   }
2940 
2941   // Perform instruction selection.  You might think we could reclaim Matcher
2942   // memory PDQ, but actually the Matcher is used in generating spill code.
2943   // Internals of the Matcher (including some VectorSets) must remain live
2944   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
2945   // set a bit in reclaimed memory.
2946 
2947   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2948   // nodes.  Mapping is only valid at the root of each matched subtree.
2949   NOT_PRODUCT( verify_graph_edges(); )
2950 
2951   Matcher matcher;
2952   _matcher = &matcher;
2953   {
2954     TracePhase tp("matcher", &timers[_t_matcher]);
2955     matcher.match();
2956     print_method(PHASE_AFTER_MATCHING, 3);
2957   }
2958   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2959   // nodes.  Mapping is only valid at the root of each matched subtree.
2960   NOT_PRODUCT( verify_graph_edges(); )
2961 
2962   // If you have too many nodes, or if matching has failed, bail out
2963   check_node_count(0, "out of nodes matching instructions");
2964   if (failing()) {
2965     return;
2966   }
2967 
2968   print_method(PHASE_MATCHING, 2);
2969 
2970   // Build a proper-looking CFG
2971   PhaseCFG cfg(node_arena(), root(), matcher);
2972   _cfg = &cfg;
2973   {
2974     TracePhase tp("scheduler", &timers[_t_scheduler]);
2975     bool success = cfg.do_global_code_motion();
2976     if (!success) {
2977       return;
2978     }
2979 
2980     print_method(PHASE_GLOBAL_CODE_MOTION, 2);
2981     NOT_PRODUCT( verify_graph_edges(); )
2982     debug_only( cfg.verify(); )
2983   }
2984 
2985   PhaseChaitin regalloc(unique(), cfg, matcher, false);
2986   _regalloc = &regalloc;
2987   {
2988     TracePhase tp("regalloc", &timers[_t_registerAllocation]);
2989     // Perform register allocation.  After Chaitin, use-def chains are
2990     // no longer accurate (at spill code) and so must be ignored.
2991     // Node->LRG->reg mappings are still accurate.
2992     _regalloc->Register_Allocate();
2993 
2994     // Bail out if the allocator builds too many nodes
2995     if (failing()) {
2996       return;
2997     }
2998   }
2999 
3000   // Prior to register allocation we kept empty basic blocks in case the
3001   // the allocator needed a place to spill.  After register allocation we
3002   // are not adding any new instructions.  If any basic block is empty, we
3003   // can now safely remove it.
3004   {
3005     TracePhase tp("blockOrdering", &timers[_t_blockOrdering]);
3006     cfg.remove_empty_blocks();
3007     if (do_freq_based_layout()) {
3008       PhaseBlockLayout layout(cfg);
3009     } else {
3010       cfg.set_loop_alignment();
3011     }
3012     cfg.fixup_flow();
3013   }
3014 
3015   // Apply peephole optimizations
3016   if( OptoPeephole ) {
3017     TracePhase tp("peephole", &timers[_t_peephole]);
3018     PhasePeephole peep( _regalloc, cfg);
3019     peep.do_transform();
3020   }
3021 
3022   // Do late expand if CPU requires this.
3023   if (Matcher::require_postalloc_expand) {
3024     TracePhase tp("postalloc_expand", &timers[_t_postalloc_expand]);
3025     cfg.postalloc_expand(_regalloc);
3026   }
3027 
3028   // Convert Nodes to instruction bits in a buffer
3029   {
3030     TraceTime tp("output", &timers[_t_output], CITime);
3031     Output();
3032   }
3033 
3034   print_method(PHASE_FINAL_CODE);
3035 
3036   // He's dead, Jim.
3037   _cfg     = (PhaseCFG*)((intptr_t)0xdeadbeef);
3038   _regalloc = (PhaseChaitin*)((intptr_t)0xdeadbeef);
3039 }
3040 
3041 
3042 //------------------------------dump_asm---------------------------------------
3043 // Dump formatted assembly
3044 #ifndef PRODUCT
3045 void Compile::dump_asm(int *pcs, uint pc_limit) {
3046   bool cut_short = false;
3047   tty->print_cr("#");
3048   tty->print("#  ");  _tf->dump();  tty->cr();
3049   tty->print_cr("#");
3050 
3051   // For all blocks
3052   int pc = 0x0;                 // Program counter
3053   char starts_bundle = ' ';
3054   _regalloc->dump_frame();
3055 
3056   Node *n = NULL;
3057   for (uint i = 0; i < _cfg->number_of_blocks(); i++) {
3058     if (VMThread::should_terminate()) {
3059       cut_short = true;
3060       break;
3061     }
3062     Block* block = _cfg->get_block(i);
3063     if (block->is_connector() && !Verbose) {
3064       continue;
3065     }
3066     n = block->head();
3067     if (pcs && n->_idx < pc_limit) {
3068       tty->print("%3.3x   ", pcs[n->_idx]);
3069     } else {
3070       tty->print("      ");
3071     }
3072     block->dump_head(_cfg);
3073     if (block->is_connector()) {
3074       tty->print_cr("        # Empty connector block");
3075     } else if (block->num_preds() == 2 && block->pred(1)->is_CatchProj() && block->pred(1)->as_CatchProj()->_con == CatchProjNode::fall_through_index) {
3076       tty->print_cr("        # Block is sole successor of call");
3077     }
3078 
3079     // For all instructions
3080     Node *delay = NULL;
3081     for (uint j = 0; j < block->number_of_nodes(); j++) {
3082       if (VMThread::should_terminate()) {
3083         cut_short = true;
3084         break;
3085       }
3086       n = block->get_node(j);
3087       if (valid_bundle_info(n)) {
3088         Bundle* bundle = node_bundling(n);
3089         if (bundle->used_in_unconditional_delay()) {
3090           delay = n;
3091           continue;
3092         }
3093         if (bundle->starts_bundle()) {
3094           starts_bundle = '+';
3095         }
3096       }
3097 
3098       if (WizardMode) {
3099         n->dump();
3100       }
3101 
3102       if( !n->is_Region() &&    // Dont print in the Assembly
3103           !n->is_Phi() &&       // a few noisely useless nodes
3104           !n->is_Proj() &&
3105           !n->is_MachTemp() &&
3106           !n->is_SafePointScalarObject() &&
3107           !n->is_Catch() &&     // Would be nice to print exception table targets
3108           !n->is_MergeMem() &&  // Not very interesting
3109           !n->is_top() &&       // Debug info table constants
3110           !(n->is_Con() && !n->is_Mach())// Debug info table constants
3111           ) {
3112         if (pcs && n->_idx < pc_limit)
3113           tty->print("%3.3x", pcs[n->_idx]);
3114         else
3115           tty->print("   ");
3116         tty->print(" %c ", starts_bundle);
3117         starts_bundle = ' ';
3118         tty->print("\t");
3119         n->format(_regalloc, tty);
3120         tty->cr();
3121       }
3122 
3123       // If we have an instruction with a delay slot, and have seen a delay,
3124       // then back up and print it
3125       if (valid_bundle_info(n) && node_bundling(n)->use_unconditional_delay()) {
3126         assert(delay != NULL, "no unconditional delay instruction");
3127         if (WizardMode) delay->dump();
3128 
3129         if (node_bundling(delay)->starts_bundle())
3130           starts_bundle = '+';
3131         if (pcs && n->_idx < pc_limit)
3132           tty->print("%3.3x", pcs[n->_idx]);
3133         else
3134           tty->print("   ");
3135         tty->print(" %c ", starts_bundle);
3136         starts_bundle = ' ';
3137         tty->print("\t");
3138         delay->format(_regalloc, tty);
3139         tty->cr();
3140         delay = NULL;
3141       }
3142 
3143       // Dump the exception table as well
3144       if( n->is_Catch() && (Verbose || WizardMode) ) {
3145         // Print the exception table for this offset
3146         _handler_table.print_subtable_for(pc);
3147       }
3148     }
3149 
3150     if (pcs && n->_idx < pc_limit)
3151       tty->print_cr("%3.3x", pcs[n->_idx]);
3152     else
3153       tty->cr();
3154 
3155     assert(cut_short || delay == NULL, "no unconditional delay branch");
3156 
3157   } // End of per-block dump
3158   tty->cr();
3159 
3160   if (cut_short)  tty->print_cr("*** disassembly is cut short ***");
3161 }
3162 #endif
3163 
3164 //------------------------------Final_Reshape_Counts---------------------------
3165 // This class defines counters to help identify when a method
3166 // may/must be executed using hardware with only 24-bit precision.
3167 struct Final_Reshape_Counts : public StackObj {
3168   int  _call_count;             // count non-inlined 'common' calls
3169   int  _float_count;            // count float ops requiring 24-bit precision
3170   int  _double_count;           // count double ops requiring more precision
3171   int  _java_call_count;        // count non-inlined 'java' calls
3172   int  _inner_loop_count;       // count loops which need alignment
3173   VectorSet _visited;           // Visitation flags
3174   Node_List _tests;             // Set of IfNodes & PCTableNodes
3175 
3176   Final_Reshape_Counts() :
3177     _call_count(0), _float_count(0), _double_count(0),
3178     _java_call_count(0), _inner_loop_count(0),
3179     _visited( Thread::current()->resource_area() ) { }
3180 
3181   void inc_call_count  () { _call_count  ++; }
3182   void inc_float_count () { _float_count ++; }
3183   void inc_double_count() { _double_count++; }
3184   void inc_java_call_count() { _java_call_count++; }
3185   void inc_inner_loop_count() { _inner_loop_count++; }
3186 
3187   int  get_call_count  () const { return _call_count  ; }
3188   int  get_float_count () const { return _float_count ; }
3189   int  get_double_count() const { return _double_count; }
3190   int  get_java_call_count() const { return _java_call_count; }
3191   int  get_inner_loop_count() const { return _inner_loop_count; }
3192 };
3193 
3194 #ifdef ASSERT
3195 static bool oop_offset_is_sane(const TypeInstPtr* tp) {
3196   ciInstanceKlass *k = tp->klass()->as_instance_klass();
3197   // Make sure the offset goes inside the instance layout.
3198   return k->contains_field_offset(tp->offset());
3199   // Note that OffsetBot and OffsetTop are very negative.
3200 }
3201 #endif
3202 
3203 // Eliminate trivially redundant StoreCMs and accumulate their
3204 // precedence edges.
3205 void Compile::eliminate_redundant_card_marks(Node* n) {
3206   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
3207   if (n->in(MemNode::Address)->outcnt() > 1) {
3208     // There are multiple users of the same address so it might be
3209     // possible to eliminate some of the StoreCMs
3210     Node* mem = n->in(MemNode::Memory);
3211     Node* adr = n->in(MemNode::Address);
3212     Node* val = n->in(MemNode::ValueIn);
3213     Node* prev = n;
3214     bool done = false;
3215     // Walk the chain of StoreCMs eliminating ones that match.  As
3216     // long as it's a chain of single users then the optimization is
3217     // safe.  Eliminating partially redundant StoreCMs would require
3218     // cloning copies down the other paths.
3219     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
3220       if (adr == mem->in(MemNode::Address) &&
3221           val == mem->in(MemNode::ValueIn)) {
3222         // redundant StoreCM
3223         if (mem->req() > MemNode::OopStore) {
3224           // Hasn't been processed by this code yet.
3225           n->add_prec(mem->in(MemNode::OopStore));
3226         } else {
3227           // Already converted to precedence edge
3228           for (uint i = mem->req(); i < mem->len(); i++) {
3229             // Accumulate any precedence edges
3230             if (mem->in(i) != NULL) {
3231               n->add_prec(mem->in(i));
3232             }
3233           }
3234           // Everything above this point has been processed.
3235           done = true;
3236         }
3237         // Eliminate the previous StoreCM
3238         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
3239         assert(mem->outcnt() == 0, "should be dead");
3240         mem->disconnect_inputs(NULL, this);
3241       } else {
3242         prev = mem;
3243       }
3244       mem = prev->in(MemNode::Memory);
3245     }
3246   }
3247 }
3248 
3249 //------------------------------final_graph_reshaping_impl----------------------
3250 // Implement items 1-5 from final_graph_reshaping below.
3251 void Compile::final_graph_reshaping_impl( Node *n, Final_Reshape_Counts &frc) {
3252 
3253   if ( n->outcnt() == 0 ) return; // dead node
3254   uint nop = n->Opcode();
3255 
3256   // Check for 2-input instruction with "last use" on right input.
3257   // Swap to left input.  Implements item (2).
3258   if( n->req() == 3 &&          // two-input instruction
3259       n->in(1)->outcnt() > 1 && // left use is NOT a last use
3260       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
3261       n->in(2)->outcnt() == 1 &&// right use IS a last use
3262       !n->in(2)->is_Con() ) {   // right use is not a constant
3263     // Check for commutative opcode
3264     switch( nop ) {
3265     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
3266     case Op_MaxI:  case Op_MaxL:  case Op_MaxF:  case Op_MaxD:
3267     case Op_MinI:  case Op_MinL:  case Op_MinF:  case Op_MinD:
3268     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
3269     case Op_AndL:  case Op_XorL:  case Op_OrL:
3270     case Op_AndI:  case Op_XorI:  case Op_OrI: {
3271       // Move "last use" input to left by swapping inputs
3272       n->swap_edges(1, 2);
3273       break;
3274     }
3275     default:
3276       break;
3277     }
3278   }
3279 
3280 #ifdef ASSERT
3281   if( n->is_Mem() ) {
3282     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
3283     assert( n->in(0) != NULL || alias_idx != Compile::AliasIdxRaw ||
3284             // oop will be recorded in oop map if load crosses safepoint
3285             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
3286                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
3287             "raw memory operations should have control edge");
3288   }
3289   if (n->is_MemBar()) {
3290     MemBarNode* mb = n->as_MemBar();
3291     if (mb->trailing_store() || mb->trailing_load_store()) {
3292       assert(mb->leading_membar()->trailing_membar() == mb, "bad membar pair");
3293       Node* mem = mb->in(MemBarNode::Precedent);
3294       assert((mb->trailing_store() && mem->is_Store() && mem->as_Store()->is_release()) ||
3295              (mb->trailing_load_store() && mem->is_LoadStore()), "missing mem op");
3296     } else if (mb->leading()) {
3297       assert(mb->trailing_membar()->leading_membar() == mb, "bad membar pair");
3298     }
3299   }
3300 #endif
3301   // Count FPU ops and common calls, implements item (3)
3302   bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->final_graph_reshaping(this, n, nop);
3303   if (!gc_handled) {
3304     final_graph_reshaping_main_switch(n, frc, nop);
3305   }
3306 
3307   // Collect CFG split points
3308   if (n->is_MultiBranch() && !n->is_RangeCheck()) {
3309     frc._tests.push(n);
3310   }
3311 }
3312 
3313 void Compile::final_graph_reshaping_main_switch(Node* n, Final_Reshape_Counts& frc, uint nop) {
3314   switch( nop ) {
3315   // Count all float operations that may use FPU
3316   case Op_AddF:
3317   case Op_SubF:
3318   case Op_MulF:
3319   case Op_DivF:
3320   case Op_NegF:
3321   case Op_ModF:
3322   case Op_ConvI2F:
3323   case Op_ConF:
3324   case Op_CmpF:
3325   case Op_CmpF3:
3326   // case Op_ConvL2F: // longs are split into 32-bit halves
3327     frc.inc_float_count();
3328     break;
3329 
3330   case Op_ConvF2D:
3331   case Op_ConvD2F:
3332     frc.inc_float_count();
3333     frc.inc_double_count();
3334     break;
3335 
3336   // Count all double operations that may use FPU
3337   case Op_AddD:
3338   case Op_SubD:
3339   case Op_MulD:
3340   case Op_DivD:
3341   case Op_NegD:
3342   case Op_ModD:
3343   case Op_ConvI2D:
3344   case Op_ConvD2I:
3345   // case Op_ConvL2D: // handled by leaf call
3346   // case Op_ConvD2L: // handled by leaf call
3347   case Op_ConD:
3348   case Op_CmpD:
3349   case Op_CmpD3:
3350     frc.inc_double_count();
3351     break;
3352   case Op_Opaque1:              // Remove Opaque Nodes before matching
3353   case Op_Opaque2:              // Remove Opaque Nodes before matching
3354   case Op_Opaque3:
3355     n->subsume_by(n->in(1), this);
3356     break;
3357   case Op_CallStaticJava:
3358   case Op_CallJava:
3359   case Op_CallDynamicJava:
3360     frc.inc_java_call_count(); // Count java call site;
3361   case Op_CallRuntime:
3362   case Op_CallLeaf:
3363   case Op_CallLeafVector:
3364   case Op_CallLeafNoFP: {
3365     assert (n->is_Call(), "");
3366     CallNode *call = n->as_Call();
3367     // Count call sites where the FP mode bit would have to be flipped.
3368     // Do not count uncommon runtime calls:
3369     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
3370     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
3371     if (!call->is_CallStaticJava() || !call->as_CallStaticJava()->_name) {
3372       frc.inc_call_count();   // Count the call site
3373     } else {                  // See if uncommon argument is shared
3374       Node *n = call->in(TypeFunc::Parms);
3375       int nop = n->Opcode();
3376       // Clone shared simple arguments to uncommon calls, item (1).
3377       if (n->outcnt() > 1 &&
3378           !n->is_Proj() &&
3379           nop != Op_CreateEx &&
3380           nop != Op_CheckCastPP &&
3381           nop != Op_DecodeN &&
3382           nop != Op_DecodeNKlass &&
3383           !n->is_Mem() &&
3384           !n->is_Phi()) {
3385         Node *x = n->clone();
3386         call->set_req(TypeFunc::Parms, x);
3387       }
3388     }
3389     break;
3390   }
3391 
3392   case Op_StoreD:
3393   case Op_LoadD:
3394   case Op_LoadD_unaligned:
3395     frc.inc_double_count();
3396     goto handle_mem;
3397   case Op_StoreF:
3398   case Op_LoadF:
3399     frc.inc_float_count();
3400     goto handle_mem;
3401 
3402   case Op_StoreCM:
3403     {
3404       // Convert OopStore dependence into precedence edge
3405       Node* prec = n->in(MemNode::OopStore);
3406       n->del_req(MemNode::OopStore);
3407       n->add_prec(prec);
3408       eliminate_redundant_card_marks(n);
3409     }
3410 
3411     // fall through
3412 
3413   case Op_StoreB:
3414   case Op_StoreC:
3415   case Op_StorePConditional:
3416   case Op_StoreI:
3417   case Op_StoreL:
3418   case Op_StoreIConditional:
3419   case Op_StoreLConditional:
3420   case Op_CompareAndSwapB:
3421   case Op_CompareAndSwapS:
3422   case Op_CompareAndSwapI:
3423   case Op_CompareAndSwapL:
3424   case Op_CompareAndSwapP:
3425   case Op_CompareAndSwapN:
3426   case Op_WeakCompareAndSwapB:
3427   case Op_WeakCompareAndSwapS:
3428   case Op_WeakCompareAndSwapI:
3429   case Op_WeakCompareAndSwapL:
3430   case Op_WeakCompareAndSwapP:
3431   case Op_WeakCompareAndSwapN:
3432   case Op_CompareAndExchangeB:
3433   case Op_CompareAndExchangeS:
3434   case Op_CompareAndExchangeI:
3435   case Op_CompareAndExchangeL:
3436   case Op_CompareAndExchangeP:
3437   case Op_CompareAndExchangeN:
3438   case Op_GetAndAddS:
3439   case Op_GetAndAddB:
3440   case Op_GetAndAddI:
3441   case Op_GetAndAddL:
3442   case Op_GetAndSetS:
3443   case Op_GetAndSetB:
3444   case Op_GetAndSetI:
3445   case Op_GetAndSetL:
3446   case Op_GetAndSetP:
3447   case Op_GetAndSetN:
3448   case Op_StoreP:
3449   case Op_StoreN:
3450   case Op_StoreNKlass:
3451   case Op_LoadB:
3452   case Op_LoadUB:
3453   case Op_LoadUS:
3454   case Op_LoadI:
3455   case Op_LoadKlass:
3456   case Op_LoadNKlass:
3457   case Op_LoadL:
3458   case Op_LoadL_unaligned:
3459   case Op_LoadPLocked:
3460   case Op_LoadP:
3461   case Op_LoadN:
3462   case Op_LoadRange:
3463   case Op_LoadS: {
3464   handle_mem:
3465 #ifdef ASSERT
3466     if( VerifyOptoOopOffsets ) {
3467       MemNode* mem  = n->as_Mem();
3468       // Check to see if address types have grounded out somehow.
3469       const TypeInstPtr *tp = mem->in(MemNode::Address)->bottom_type()->isa_instptr();
3470       assert( !tp || oop_offset_is_sane(tp), "" );
3471     }
3472 #endif
3473     break;
3474   }
3475 
3476   case Op_AddP: {               // Assert sane base pointers
3477     Node *addp = n->in(AddPNode::Address);
3478     assert( !addp->is_AddP() ||
3479             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
3480             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
3481             "Base pointers must match (addp %u)", addp->_idx );
3482 #ifdef _LP64
3483     if ((UseCompressedOops || UseCompressedClassPointers) &&
3484         addp->Opcode() == Op_ConP &&
3485         addp == n->in(AddPNode::Base) &&
3486         n->in(AddPNode::Offset)->is_Con()) {
3487       // If the transformation of ConP to ConN+DecodeN is beneficial depends
3488       // on the platform and on the compressed oops mode.
3489       // Use addressing with narrow klass to load with offset on x86.
3490       // Some platforms can use the constant pool to load ConP.
3491       // Do this transformation here since IGVN will convert ConN back to ConP.
3492       const Type* t = addp->bottom_type();
3493       bool is_oop   = t->isa_oopptr() != NULL;
3494       bool is_klass = t->isa_klassptr() != NULL;
3495 
3496       if ((is_oop   && Matcher::const_oop_prefer_decode()  ) ||
3497           (is_klass && Matcher::const_klass_prefer_decode())) {
3498         Node* nn = NULL;
3499 
3500         int op = is_oop ? Op_ConN : Op_ConNKlass;
3501 
3502         // Look for existing ConN node of the same exact type.
3503         Node* r  = root();
3504         uint cnt = r->outcnt();
3505         for (uint i = 0; i < cnt; i++) {
3506           Node* m = r->raw_out(i);
3507           if (m!= NULL && m->Opcode() == op &&
3508               m->bottom_type()->make_ptr() == t) {
3509             nn = m;
3510             break;
3511           }
3512         }
3513         if (nn != NULL) {
3514           // Decode a narrow oop to match address
3515           // [R12 + narrow_oop_reg<<3 + offset]
3516           if (is_oop) {
3517             nn = new DecodeNNode(nn, t);
3518           } else {
3519             nn = new DecodeNKlassNode(nn, t);
3520           }
3521           // Check for succeeding AddP which uses the same Base.
3522           // Otherwise we will run into the assertion above when visiting that guy.
3523           for (uint i = 0; i < n->outcnt(); ++i) {
3524             Node *out_i = n->raw_out(i);
3525             if (out_i && out_i->is_AddP() && out_i->in(AddPNode::Base) == addp) {
3526               out_i->set_req(AddPNode::Base, nn);
3527 #ifdef ASSERT
3528               for (uint j = 0; j < out_i->outcnt(); ++j) {
3529                 Node *out_j = out_i->raw_out(j);
3530                 assert(out_j == NULL || !out_j->is_AddP() || out_j->in(AddPNode::Base) != addp,
3531                        "more than 2 AddP nodes in a chain (out_j %u)", out_j->_idx);
3532               }
3533 #endif
3534             }
3535           }
3536           n->set_req(AddPNode::Base, nn);
3537           n->set_req(AddPNode::Address, nn);
3538           if (addp->outcnt() == 0) {
3539             addp->disconnect_inputs(NULL, this);
3540           }
3541         }
3542       }
3543     }
3544 #endif
3545     // platform dependent reshaping of the address expression
3546     reshape_address(n->as_AddP());
3547     break;
3548   }
3549 
3550   case Op_CastPP: {
3551     // Remove CastPP nodes to gain more freedom during scheduling but
3552     // keep the dependency they encode as control or precedence edges
3553     // (if control is set already) on memory operations. Some CastPP
3554     // nodes don't have a control (don't carry a dependency): skip
3555     // those.
3556     if (n->in(0) != NULL) {
3557       ResourceMark rm;
3558       Unique_Node_List wq;
3559       wq.push(n);
3560       for (uint next = 0; next < wq.size(); ++next) {
3561         Node *m = wq.at(next);
3562         for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
3563           Node* use = m->fast_out(i);
3564           if (use->is_Mem() || use->is_EncodeNarrowPtr() || use->is_ShenandoahBarrier()) {
3565             use->ensure_control_or_add_prec(n->in(0));
3566           } else {
3567             switch(use->Opcode()) {
3568             case Op_AddP:
3569             case Op_DecodeN:
3570             case Op_DecodeNKlass:
3571             case Op_CheckCastPP:
3572             case Op_CastPP:
3573               wq.push(use);
3574               break;
3575             }
3576           }
3577         }
3578       }
3579     }
3580     const bool is_LP64 = LP64_ONLY(true) NOT_LP64(false);
3581     if (is_LP64 && n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
3582       Node* in1 = n->in(1);
3583       const Type* t = n->bottom_type();
3584       Node* new_in1 = in1->clone();
3585       new_in1->as_DecodeN()->set_type(t);
3586 
3587       if (!Matcher::narrow_oop_use_complex_address()) {
3588         //
3589         // x86, ARM and friends can handle 2 adds in addressing mode
3590         // and Matcher can fold a DecodeN node into address by using
3591         // a narrow oop directly and do implicit NULL check in address:
3592         //
3593         // [R12 + narrow_oop_reg<<3 + offset]
3594         // NullCheck narrow_oop_reg
3595         //
3596         // On other platforms (Sparc) we have to keep new DecodeN node and
3597         // use it to do implicit NULL check in address:
3598         //
3599         // decode_not_null narrow_oop_reg, base_reg
3600         // [base_reg + offset]
3601         // NullCheck base_reg
3602         //
3603         // Pin the new DecodeN node to non-null path on these platform (Sparc)
3604         // to keep the information to which NULL check the new DecodeN node
3605         // corresponds to use it as value in implicit_null_check().
3606         //
3607         new_in1->set_req(0, n->in(0));
3608       }
3609 
3610       n->subsume_by(new_in1, this);
3611       if (in1->outcnt() == 0) {
3612         in1->disconnect_inputs(NULL, this);
3613       }
3614     } else {
3615       n->subsume_by(n->in(1), this);
3616       if (n->outcnt() == 0) {
3617         n->disconnect_inputs(NULL, this);
3618       }
3619     }
3620     break;
3621   }
3622 #ifdef _LP64
3623   case Op_CmpP:
3624     // Do this transformation here to preserve CmpPNode::sub() and
3625     // other TypePtr related Ideal optimizations (for example, ptr nullness).
3626     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
3627       Node* in1 = n->in(1);
3628       Node* in2 = n->in(2);
3629       if (!in1->is_DecodeNarrowPtr()) {
3630         in2 = in1;
3631         in1 = n->in(2);
3632       }
3633       assert(in1->is_DecodeNarrowPtr(), "sanity");
3634 
3635       Node* new_in2 = NULL;
3636       if (in2->is_DecodeNarrowPtr()) {
3637         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
3638         new_in2 = in2->in(1);
3639       } else if (in2->Opcode() == Op_ConP) {
3640         const Type* t = in2->bottom_type();
3641         if (t == TypePtr::NULL_PTR) {
3642           assert(in1->is_DecodeN(), "compare klass to null?");
3643           // Don't convert CmpP null check into CmpN if compressed
3644           // oops implicit null check is not generated.
3645           // This will allow to generate normal oop implicit null check.
3646           if (Matcher::gen_narrow_oop_implicit_null_checks())
3647             new_in2 = ConNode::make(TypeNarrowOop::NULL_PTR);
3648           //
3649           // This transformation together with CastPP transformation above
3650           // will generated code for implicit NULL checks for compressed oops.
3651           //
3652           // The original code after Optimize()
3653           //
3654           //    LoadN memory, narrow_oop_reg
3655           //    decode narrow_oop_reg, base_reg
3656           //    CmpP base_reg, NULL
3657           //    CastPP base_reg // NotNull
3658           //    Load [base_reg + offset], val_reg
3659           //
3660           // after these transformations will be
3661           //
3662           //    LoadN memory, narrow_oop_reg
3663           //    CmpN narrow_oop_reg, NULL
3664           //    decode_not_null narrow_oop_reg, base_reg
3665           //    Load [base_reg + offset], val_reg
3666           //
3667           // and the uncommon path (== NULL) will use narrow_oop_reg directly
3668           // since narrow oops can be used in debug info now (see the code in
3669           // final_graph_reshaping_walk()).
3670           //
3671           // At the end the code will be matched to
3672           // on x86:
3673           //
3674           //    Load_narrow_oop memory, narrow_oop_reg
3675           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
3676           //    NullCheck narrow_oop_reg
3677           //
3678           // and on sparc:
3679           //
3680           //    Load_narrow_oop memory, narrow_oop_reg
3681           //    decode_not_null narrow_oop_reg, base_reg
3682           //    Load [base_reg + offset], val_reg
3683           //    NullCheck base_reg
3684           //
3685         } else if (t->isa_oopptr()) {
3686           new_in2 = ConNode::make(t->make_narrowoop());
3687         } else if (t->isa_klassptr()) {
3688           new_in2 = ConNode::make(t->make_narrowklass());
3689         }
3690       }
3691       if (new_in2 != NULL) {
3692         Node* cmpN = new CmpNNode(in1->in(1), new_in2);
3693         n->subsume_by(cmpN, this);
3694         if (in1->outcnt() == 0) {
3695           in1->disconnect_inputs(NULL, this);
3696         }
3697         if (in2->outcnt() == 0) {
3698           in2->disconnect_inputs(NULL, this);
3699         }
3700       }
3701     }
3702     break;
3703 
3704   case Op_DecodeN:
3705   case Op_DecodeNKlass:
3706     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
3707     // DecodeN could be pinned when it can't be fold into
3708     // an address expression, see the code for Op_CastPP above.
3709     assert(n->in(0) == NULL || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
3710     break;
3711 
3712   case Op_EncodeP:
3713   case Op_EncodePKlass: {
3714     Node* in1 = n->in(1);
3715     if (in1->is_DecodeNarrowPtr()) {
3716       n->subsume_by(in1->in(1), this);
3717     } else if (in1->Opcode() == Op_ConP) {
3718       const Type* t = in1->bottom_type();
3719       if (t == TypePtr::NULL_PTR) {
3720         assert(t->isa_oopptr(), "null klass?");
3721         n->subsume_by(ConNode::make(TypeNarrowOop::NULL_PTR), this);
3722       } else if (t->isa_oopptr()) {
3723         n->subsume_by(ConNode::make(t->make_narrowoop()), this);
3724       } else if (t->isa_klassptr()) {
3725         n->subsume_by(ConNode::make(t->make_narrowklass()), this);
3726       }
3727     }
3728     if (in1->outcnt() == 0) {
3729       in1->disconnect_inputs(NULL, this);
3730     }
3731     break;
3732   }
3733 
3734   case Op_Proj: {
3735     if (OptimizeStringConcat) {
3736       ProjNode* p = n->as_Proj();
3737       if (p->_is_io_use) {
3738         // Separate projections were used for the exception path which
3739         // are normally removed by a late inline.  If it wasn't inlined
3740         // then they will hang around and should just be replaced with
3741         // the original one.
3742         Node* proj = NULL;
3743         // Replace with just one
3744         for (SimpleDUIterator i(p->in(0)); i.has_next(); i.next()) {
3745           Node *use = i.get();
3746           if (use->is_Proj() && p != use && use->as_Proj()->_con == p->_con) {
3747             proj = use;
3748             break;
3749           }
3750         }
3751         assert(proj != NULL || p->_con == TypeFunc::I_O, "io may be dropped at an infinite loop");
3752         if (proj != NULL) {
3753           p->subsume_by(proj, this);
3754         }
3755       }
3756     }
3757     break;
3758   }
3759 
3760   case Op_Phi:
3761     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
3762       // The EncodeP optimization may create Phi with the same edges
3763       // for all paths. It is not handled well by Register Allocator.
3764       Node* unique_in = n->in(1);
3765       assert(unique_in != NULL, "");
3766       uint cnt = n->req();
3767       for (uint i = 2; i < cnt; i++) {
3768         Node* m = n->in(i);
3769         assert(m != NULL, "");
3770         if (unique_in != m)
3771           unique_in = NULL;
3772       }
3773       if (unique_in != NULL) {
3774         n->subsume_by(unique_in, this);
3775       }
3776     }
3777     break;
3778 
3779 #endif
3780 
3781 #ifdef ASSERT
3782   case Op_CastII:
3783     // Verify that all range check dependent CastII nodes were removed.
3784     if (n->isa_CastII()->has_range_check()) {
3785       n->dump(3);
3786       assert(false, "Range check dependent CastII node was not removed");
3787     }
3788     break;
3789 #endif
3790 
3791   case Op_ModI:
3792     if (UseDivMod) {
3793       // Check if a%b and a/b both exist
3794       Node* d = n->find_similar(Op_DivI);
3795       if (d) {
3796         // Replace them with a fused divmod if supported
3797         if (Matcher::has_match_rule(Op_DivModI)) {
3798           DivModINode* divmod = DivModINode::make(n);
3799           d->subsume_by(divmod->div_proj(), this);
3800           n->subsume_by(divmod->mod_proj(), this);
3801         } else {
3802           // replace a%b with a-((a/b)*b)
3803           Node* mult = new MulINode(d, d->in(2));
3804           Node* sub  = new SubINode(d->in(1), mult);
3805           n->subsume_by(sub, this);
3806         }
3807       }
3808     }
3809     break;
3810 
3811   case Op_ModL:
3812     if (UseDivMod) {
3813       // Check if a%b and a/b both exist
3814       Node* d = n->find_similar(Op_DivL);
3815       if (d) {
3816         // Replace them with a fused divmod if supported
3817         if (Matcher::has_match_rule(Op_DivModL)) {
3818           DivModLNode* divmod = DivModLNode::make(n);
3819           d->subsume_by(divmod->div_proj(), this);
3820           n->subsume_by(divmod->mod_proj(), this);
3821         } else {
3822           // replace a%b with a-((a/b)*b)
3823           Node* mult = new MulLNode(d, d->in(2));
3824           Node* sub  = new SubLNode(d->in(1), mult);
3825           n->subsume_by(sub, this);
3826         }
3827       }
3828     }
3829     break;
3830 
3831   case Op_LoadVector:
3832   case Op_StoreVector:
3833   case Op_LoadVectorGather:
3834   case Op_StoreVectorScatter:
3835     break;
3836 
3837   case Op_AddReductionVI:
3838   case Op_AddReductionVL:
3839   case Op_AddReductionVF:
3840   case Op_AddReductionVD:
3841   case Op_MulReductionVI:
3842   case Op_MulReductionVL:
3843   case Op_MulReductionVF:
3844   case Op_MulReductionVD:
3845   case Op_MinReductionV:
3846   case Op_MaxReductionV:
3847   case Op_AndReductionV:
3848   case Op_OrReductionV:
3849   case Op_XorReductionV:
3850   case Op_SubReductionV:
3851   case Op_SubReductionVFP:
3852     break;
3853 
3854   case Op_PackB:
3855   case Op_PackS:
3856   case Op_PackI:
3857   case Op_PackF:
3858   case Op_PackL:
3859   case Op_PackD:
3860     if (n->req()-1 > 2) {
3861       // Replace many operand PackNodes with a binary tree for matching
3862       PackNode* p = (PackNode*) n;
3863       Node* btp = p->binary_tree_pack(1, n->req());
3864       n->subsume_by(btp, this);
3865     }
3866     break;
3867   case Op_Loop:
3868   case Op_CountedLoop:
3869   case Op_OuterStripMinedLoop:
3870     if (n->as_Loop()->is_inner_loop()) {
3871       frc.inc_inner_loop_count();
3872     }
3873     n->as_Loop()->verify_strip_mined(0);
3874     break;
3875   case Op_LShiftI:
3876   case Op_RShiftI:
3877   case Op_URShiftI:
3878   case Op_LShiftL:
3879   case Op_RShiftL:
3880   case Op_URShiftL:
3881     if (Matcher::need_masked_shift_count) {
3882       // The cpu's shift instructions don't restrict the count to the
3883       // lower 5/6 bits. We need to do the masking ourselves.
3884       Node* in2 = n->in(2);
3885       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
3886       const TypeInt* t = in2->find_int_type();
3887       if (t != NULL && t->is_con()) {
3888         juint shift = t->get_con();
3889         if (shift > mask) { // Unsigned cmp
3890           n->set_req(2, ConNode::make(TypeInt::make(shift & mask)));
3891         }
3892       } else {
3893         if (t == NULL || t->_lo < 0 || t->_hi > (int)mask) {
3894           Node* shift = new AndINode(in2, ConNode::make(TypeInt::make(mask)));
3895           n->set_req(2, shift);
3896         }
3897       }
3898       if (in2->outcnt() == 0) { // Remove dead node
3899         in2->disconnect_inputs(NULL, this);
3900       }
3901     }
3902     break;
3903   case Op_MemBarStoreStore:
3904   case Op_MemBarRelease:
3905     // Break the link with AllocateNode: it is no longer useful and
3906     // confuses register allocation.
3907     if (n->req() > MemBarNode::Precedent) {
3908       n->set_req(MemBarNode::Precedent, top());
3909     }
3910     break;
3911   case Op_MemBarAcquire: {
3912     if (n->as_MemBar()->trailing_load() && n->req() > MemBarNode::Precedent) {
3913       // At parse time, the trailing MemBarAcquire for a volatile load
3914       // is created with an edge to the load. After optimizations,
3915       // that input may be a chain of Phis. If those phis have no
3916       // other use, then the MemBarAcquire keeps them alive and
3917       // register allocation can be confused.
3918       ResourceMark rm;
3919       Unique_Node_List wq;
3920       wq.push(n->in(MemBarNode::Precedent));
3921       n->set_req(MemBarNode::Precedent, top());
3922       while (wq.size() > 0) {
3923         Node* m = wq.pop();
3924         if (m->outcnt() == 0) {
3925           for (uint j = 0; j < m->req(); j++) {
3926             Node* in = m->in(j);
3927             if (in != NULL) {
3928               wq.push(in);
3929             }
3930           }
3931           m->disconnect_inputs(NULL, this);
3932         }
3933       }
3934     }
3935     break;
3936   }
3937   case Op_RangeCheck: {
3938     RangeCheckNode* rc = n->as_RangeCheck();
3939     Node* iff = new IfNode(rc->in(0), rc->in(1), rc->_prob, rc->_fcnt);
3940     n->subsume_by(iff, this);
3941     frc._tests.push(iff);
3942     break;
3943   }
3944   case Op_ConvI2L: {
3945     if (!Matcher::convi2l_type_required) {
3946       // Code generation on some platforms doesn't need accurate
3947       // ConvI2L types. Widening the type can help remove redundant
3948       // address computations.
3949       n->as_Type()->set_type(TypeLong::INT);
3950       ResourceMark rm;
3951       Node_List wq;
3952       wq.push(n);
3953       for (uint next = 0; next < wq.size(); next++) {
3954         Node *m = wq.at(next);
3955 
3956         for(;;) {
3957           // Loop over all nodes with identical inputs edges as m
3958           Node* k = m->find_similar(m->Opcode());
3959           if (k == NULL) {
3960             break;
3961           }
3962           // Push their uses so we get a chance to remove node made
3963           // redundant
3964           for (DUIterator_Fast imax, i = k->fast_outs(imax); i < imax; i++) {
3965             Node* u = k->fast_out(i);
3966             assert(!wq.contains(u), "shouldn't process one node several times");
3967             if (u->Opcode() == Op_LShiftL ||
3968                 u->Opcode() == Op_AddL ||
3969                 u->Opcode() == Op_SubL ||
3970                 u->Opcode() == Op_AddP) {
3971               wq.push(u);
3972             }
3973           }
3974           // Replace all nodes with identical edges as m with m
3975           k->subsume_by(m, this);
3976         }
3977       }
3978     }
3979     break;
3980   }
3981   case Op_CmpUL: {
3982     if (!Matcher::has_match_rule(Op_CmpUL)) {
3983       // No support for unsigned long comparisons
3984       ConINode* sign_pos = new ConINode(TypeInt::make(BitsPerLong - 1));
3985       Node* sign_bit_mask = new RShiftLNode(n->in(1), sign_pos);
3986       Node* orl = new OrLNode(n->in(1), sign_bit_mask);
3987       ConLNode* remove_sign_mask = new ConLNode(TypeLong::make(max_jlong));
3988       Node* andl = new AndLNode(orl, remove_sign_mask);
3989       Node* cmp = new CmpLNode(andl, n->in(2));
3990       n->subsume_by(cmp, this);
3991     }
3992     break;
3993   }
3994   default:
3995     assert(!n->is_Call(), "");
3996     assert(!n->is_Mem(), "");
3997     assert(nop != Op_ProfileBoolean, "should be eliminated during IGVN");
3998     break;
3999   }
4000 }
4001 
4002 //------------------------------final_graph_reshaping_walk---------------------
4003 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
4004 // requires that the walk visits a node's inputs before visiting the node.
4005 void Compile::final_graph_reshaping_walk( Node_Stack &nstack, Node *root, Final_Reshape_Counts &frc ) {
4006   ResourceArea *area = Thread::current()->resource_area();
4007   Unique_Node_List sfpt(area);
4008 
4009   frc._visited.set(root->_idx); // first, mark node as visited
4010   uint cnt = root->req();
4011   Node *n = root;
4012   uint  i = 0;
4013   while (true) {
4014     if (i < cnt) {
4015       // Place all non-visited non-null inputs onto stack
4016       Node* m = n->in(i);
4017       ++i;
4018       if (m != NULL && !frc._visited.test_set(m->_idx)) {
4019         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != NULL) {
4020           // compute worst case interpreter size in case of a deoptimization
4021           update_interpreter_frame_size(m->as_SafePoint()->jvms()->interpreter_frame_size());
4022 
4023           sfpt.push(m);
4024         }
4025         cnt = m->req();
4026         nstack.push(n, i); // put on stack parent and next input's index
4027         n = m;
4028         i = 0;
4029       }
4030     } else {
4031       // Now do post-visit work
4032       final_graph_reshaping_impl( n, frc );
4033       if (nstack.is_empty())
4034         break;             // finished
4035       n = nstack.node();   // Get node from stack
4036       cnt = n->req();
4037       i = nstack.index();
4038       nstack.pop();        // Shift to the next node on stack
4039     }
4040   }
4041 
4042   // Skip next transformation if compressed oops are not used.
4043   if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
4044       (!UseCompressedOops && !UseCompressedClassPointers))
4045     return;
4046 
4047   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
4048   // It could be done for an uncommon traps or any safepoints/calls
4049   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
4050   while (sfpt.size() > 0) {
4051     n = sfpt.pop();
4052     JVMState *jvms = n->as_SafePoint()->jvms();
4053     assert(jvms != NULL, "sanity");
4054     int start = jvms->debug_start();
4055     int end   = n->req();
4056     bool is_uncommon = (n->is_CallStaticJava() &&
4057                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
4058     for (int j = start; j < end; j++) {
4059       Node* in = n->in(j);
4060       if (in->is_DecodeNarrowPtr()) {
4061         bool safe_to_skip = true;
4062         if (!is_uncommon ) {
4063           // Is it safe to skip?
4064           for (uint i = 0; i < in->outcnt(); i++) {
4065             Node* u = in->raw_out(i);
4066             if (!u->is_SafePoint() ||
4067                 (u->is_Call() && u->as_Call()->has_non_debug_use(n))) {
4068               safe_to_skip = false;
4069             }
4070           }
4071         }
4072         if (safe_to_skip) {
4073           n->set_req(j, in->in(1));
4074         }
4075         if (in->outcnt() == 0) {
4076           in->disconnect_inputs(NULL, this);
4077         }
4078       }
4079     }
4080   }
4081 }
4082 
4083 //------------------------------final_graph_reshaping--------------------------
4084 // Final Graph Reshaping.
4085 //
4086 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
4087 //     and not commoned up and forced early.  Must come after regular
4088 //     optimizations to avoid GVN undoing the cloning.  Clone constant
4089 //     inputs to Loop Phis; these will be split by the allocator anyways.
4090 //     Remove Opaque nodes.
4091 // (2) Move last-uses by commutative operations to the left input to encourage
4092 //     Intel update-in-place two-address operations and better register usage
4093 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
4094 //     calls canonicalizing them back.
4095 // (3) Count the number of double-precision FP ops, single-precision FP ops
4096 //     and call sites.  On Intel, we can get correct rounding either by
4097 //     forcing singles to memory (requires extra stores and loads after each
4098 //     FP bytecode) or we can set a rounding mode bit (requires setting and
4099 //     clearing the mode bit around call sites).  The mode bit is only used
4100 //     if the relative frequency of single FP ops to calls is low enough.
4101 //     This is a key transform for SPEC mpeg_audio.
4102 // (4) Detect infinite loops; blobs of code reachable from above but not
4103 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
4104 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
4105 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
4106 //     Detection is by looking for IfNodes where only 1 projection is
4107 //     reachable from below or CatchNodes missing some targets.
4108 // (5) Assert for insane oop offsets in debug mode.
4109 
4110 bool Compile::final_graph_reshaping() {
4111   // an infinite loop may have been eliminated by the optimizer,
4112   // in which case the graph will be empty.
4113   if (root()->req() == 1) {
4114     record_method_not_compilable("trivial infinite loop");
4115     return true;
4116   }
4117 
4118   // Expensive nodes have their control input set to prevent the GVN
4119   // from freely commoning them. There's no GVN beyond this point so
4120   // no need to keep the control input. We want the expensive nodes to
4121   // be freely moved to the least frequent code path by gcm.
4122   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
4123   for (int i = 0; i < expensive_count(); i++) {
4124     _expensive_nodes->at(i)->set_req(0, NULL);
4125   }
4126 
4127   Final_Reshape_Counts frc;
4128 
4129   // Visit everybody reachable!
4130   // Allocate stack of size C->live_nodes()/2 to avoid frequent realloc
4131   Node_Stack nstack(live_nodes() >> 1);
4132   final_graph_reshaping_walk(nstack, root(), frc);
4133 
4134   // Check for unreachable (from below) code (i.e., infinite loops).
4135   for( uint i = 0; i < frc._tests.size(); i++ ) {
4136     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
4137     // Get number of CFG targets.
4138     // Note that PCTables include exception targets after calls.
4139     uint required_outcnt = n->required_outcnt();
4140     if (n->outcnt() != required_outcnt) {
4141       // Check for a few special cases.  Rethrow Nodes never take the
4142       // 'fall-thru' path, so expected kids is 1 less.
4143       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
4144         if (n->in(0)->in(0)->is_Call()) {
4145           CallNode *call = n->in(0)->in(0)->as_Call();
4146           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
4147             required_outcnt--;      // Rethrow always has 1 less kid
4148           } else if (call->req() > TypeFunc::Parms &&
4149                      call->is_CallDynamicJava()) {
4150             // Check for null receiver. In such case, the optimizer has
4151             // detected that the virtual call will always result in a null
4152             // pointer exception. The fall-through projection of this CatchNode
4153             // will not be populated.
4154             Node *arg0 = call->in(TypeFunc::Parms);
4155             if (arg0->is_Type() &&
4156                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
4157               required_outcnt--;
4158             }
4159           } else if (call->entry_point() == OptoRuntime::new_array_Java() &&
4160                      call->req() > TypeFunc::Parms+1 &&
4161                      call->is_CallStaticJava()) {
4162             // Check for negative array length. In such case, the optimizer has
4163             // detected that the allocation attempt will always result in an
4164             // exception. There is no fall-through projection of this CatchNode .
4165             Node *arg1 = call->in(TypeFunc::Parms+1);
4166             if (arg1->is_Type() &&
4167                 arg1->as_Type()->type()->join(TypeInt::POS)->empty()) {
4168               required_outcnt--;
4169             }
4170           }
4171         }
4172       }
4173       // Recheck with a better notion of 'required_outcnt'
4174       if (n->outcnt() != required_outcnt) {
4175         record_method_not_compilable("malformed control flow");
4176         return true;            // Not all targets reachable!
4177       }
4178     }
4179     // Check that I actually visited all kids.  Unreached kids
4180     // must be infinite loops.
4181     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
4182       if (!frc._visited.test(n->fast_out(j)->_idx)) {
4183         record_method_not_compilable("infinite loop");
4184         return true;            // Found unvisited kid; must be unreach
4185       }
4186 
4187     // Here so verification code in final_graph_reshaping_walk()
4188     // always see an OuterStripMinedLoopEnd
4189     if (n->is_OuterStripMinedLoopEnd()) {
4190       IfNode* init_iff = n->as_If();
4191       Node* iff = new IfNode(init_iff->in(0), init_iff->in(1), init_iff->_prob, init_iff->_fcnt);
4192       n->subsume_by(iff, this);
4193     }
4194   }
4195 
4196   // If original bytecodes contained a mixture of floats and doubles
4197   // check if the optimizer has made it homogenous, item (3).
4198   if( Use24BitFPMode && Use24BitFP && UseSSE == 0 &&
4199       frc.get_float_count() > 32 &&
4200       frc.get_double_count() == 0 &&
4201       (10 * frc.get_call_count() < frc.get_float_count()) ) {
4202     set_24_bit_selection_and_mode( false,  true );
4203   }
4204 
4205   set_java_calls(frc.get_java_call_count());
4206   set_inner_loops(frc.get_inner_loop_count());
4207 
4208   // No infinite loops, no reason to bail out.
4209   return false;
4210 }
4211 
4212 //-----------------------------too_many_traps----------------------------------
4213 // Report if there are too many traps at the current method and bci.
4214 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
4215 bool Compile::too_many_traps(ciMethod* method,
4216                              int bci,
4217                              Deoptimization::DeoptReason reason) {
4218   ciMethodData* md = method->method_data();
4219   if (md->is_empty()) {
4220     // Assume the trap has not occurred, or that it occurred only
4221     // because of a transient condition during start-up in the interpreter.
4222     return false;
4223   }
4224   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
4225   if (md->has_trap_at(bci, m, reason) != 0) {
4226     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
4227     // Also, if there are multiple reasons, or if there is no per-BCI record,
4228     // assume the worst.
4229     if (log())
4230       log()->elem("observe trap='%s' count='%d'",
4231                   Deoptimization::trap_reason_name(reason),
4232                   md->trap_count(reason));
4233     return true;
4234   } else {
4235     // Ignore method/bci and see if there have been too many globally.
4236     return too_many_traps(reason, md);
4237   }
4238 }
4239 
4240 // Less-accurate variant which does not require a method and bci.
4241 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
4242                              ciMethodData* logmd) {
4243   if (trap_count(reason) >= Deoptimization::per_method_trap_limit(reason)) {
4244     // Too many traps globally.
4245     // Note that we use cumulative trap_count, not just md->trap_count.
4246     if (log()) {
4247       int mcount = (logmd == NULL)? -1: (int)logmd->trap_count(reason);
4248       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
4249                   Deoptimization::trap_reason_name(reason),
4250                   mcount, trap_count(reason));
4251     }
4252     return true;
4253   } else {
4254     // The coast is clear.
4255     return false;
4256   }
4257 }
4258 
4259 //--------------------------too_many_recompiles--------------------------------
4260 // Report if there are too many recompiles at the current method and bci.
4261 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
4262 // Is not eager to return true, since this will cause the compiler to use
4263 // Action_none for a trap point, to avoid too many recompilations.
4264 bool Compile::too_many_recompiles(ciMethod* method,
4265                                   int bci,
4266                                   Deoptimization::DeoptReason reason) {
4267   ciMethodData* md = method->method_data();
4268   if (md->is_empty()) {
4269     // Assume the trap has not occurred, or that it occurred only
4270     // because of a transient condition during start-up in the interpreter.
4271     return false;
4272   }
4273   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
4274   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
4275   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
4276   Deoptimization::DeoptReason per_bc_reason
4277     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
4278   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : NULL;
4279   if ((per_bc_reason == Deoptimization::Reason_none
4280        || md->has_trap_at(bci, m, reason) != 0)
4281       // The trap frequency measure we care about is the recompile count:
4282       && md->trap_recompiled_at(bci, m)
4283       && md->overflow_recompile_count() >= bc_cutoff) {
4284     // Do not emit a trap here if it has already caused recompilations.
4285     // Also, if there are multiple reasons, or if there is no per-BCI record,
4286     // assume the worst.
4287     if (log())
4288       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
4289                   Deoptimization::trap_reason_name(reason),
4290                   md->trap_count(reason),
4291                   md->overflow_recompile_count());
4292     return true;
4293   } else if (trap_count(reason) != 0
4294              && decompile_count() >= m_cutoff) {
4295     // Too many recompiles globally, and we have seen this sort of trap.
4296     // Use cumulative decompile_count, not just md->decompile_count.
4297     if (log())
4298       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
4299                   Deoptimization::trap_reason_name(reason),
4300                   md->trap_count(reason), trap_count(reason),
4301                   md->decompile_count(), decompile_count());
4302     return true;
4303   } else {
4304     // The coast is clear.
4305     return false;
4306   }
4307 }
4308 
4309 // Compute when not to trap. Used by matching trap based nodes and
4310 // NullCheck optimization.
4311 void Compile::set_allowed_deopt_reasons() {
4312   _allowed_reasons = 0;
4313   if (is_method_compilation()) {
4314     for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
4315       assert(rs < BitsPerInt, "recode bit map");
4316       if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
4317         _allowed_reasons |= nth_bit(rs);
4318       }
4319     }
4320   }
4321 }
4322 
4323 bool Compile::is_compiling_clinit_for(ciKlass* k) {
4324   ciMethod* root = method(); // the root method of compilation
4325   return root->is_static_initializer() && root->holder() == k; // access in the context of clinit
4326 }
4327 
4328 #ifndef PRODUCT
4329 //------------------------------verify_graph_edges---------------------------
4330 // Walk the Graph and verify that there is a one-to-one correspondence
4331 // between Use-Def edges and Def-Use edges in the graph.
4332 void Compile::verify_graph_edges(bool no_dead_code) {
4333   if (VerifyGraphEdges) {
4334     ResourceArea *area = Thread::current()->resource_area();
4335     Unique_Node_List visited(area);
4336     // Call recursive graph walk to check edges
4337     _root->verify_edges(visited);
4338     if (no_dead_code) {
4339       // Now make sure that no visited node is used by an unvisited node.
4340       bool dead_nodes = false;
4341       Unique_Node_List checked(area);
4342       while (visited.size() > 0) {
4343         Node* n = visited.pop();
4344         checked.push(n);
4345         for (uint i = 0; i < n->outcnt(); i++) {
4346           Node* use = n->raw_out(i);
4347           if (checked.member(use))  continue;  // already checked
4348           if (visited.member(use))  continue;  // already in the graph
4349           if (use->is_Con())        continue;  // a dead ConNode is OK
4350           // At this point, we have found a dead node which is DU-reachable.
4351           if (!dead_nodes) {
4352             tty->print_cr("*** Dead nodes reachable via DU edges:");
4353             dead_nodes = true;
4354           }
4355           use->dump(2);
4356           tty->print_cr("---");
4357           checked.push(use);  // No repeats; pretend it is now checked.
4358         }
4359       }
4360       assert(!dead_nodes, "using nodes must be reachable from root");
4361     }
4362   }
4363 }
4364 #endif
4365 
4366 // The Compile object keeps track of failure reasons separately from the ciEnv.
4367 // This is required because there is not quite a 1-1 relation between the
4368 // ciEnv and its compilation task and the Compile object.  Note that one
4369 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
4370 // to backtrack and retry without subsuming loads.  Other than this backtracking
4371 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
4372 // by the logic in C2Compiler.
4373 void Compile::record_failure(const char* reason) {
4374   if (log() != NULL) {
4375     log()->elem("failure reason='%s' phase='compile'", reason);
4376   }
4377   if (_failure_reason == NULL) {
4378     // Record the first failure reason.
4379     _failure_reason = reason;
4380   }
4381 
4382   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
4383     C->print_method(PHASE_FAILURE);
4384   }
4385   _root = NULL;  // flush the graph, too
4386 }
4387 
4388 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator)
4389   : TraceTime(name, accumulator, CITime, CITimeVerbose),
4390     _phase_name(name), _dolog(CITimeVerbose)
4391 {
4392   if (_dolog) {
4393     C = Compile::current();
4394     _log = C->log();
4395   } else {
4396     C = NULL;
4397     _log = NULL;
4398   }
4399   if (_log != NULL) {
4400     _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
4401     _log->stamp();
4402     _log->end_head();
4403   }
4404 }
4405 
4406 Compile::TracePhase::~TracePhase() {
4407 
4408   C = Compile::current();
4409   if (_dolog) {
4410     _log = C->log();
4411   } else {
4412     _log = NULL;
4413   }
4414 
4415 #ifdef ASSERT
4416   if (PrintIdealNodeCount) {
4417     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
4418                   _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
4419   }
4420 
4421   if (VerifyIdealNodeCount) {
4422     Compile::current()->print_missing_nodes();
4423   }
4424 #endif
4425 
4426   if (_log != NULL) {
4427     _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
4428   }
4429 }
4430 
4431 //=============================================================================
4432 // Two Constant's are equal when the type and the value are equal.
4433 bool Compile::Constant::operator==(const Constant& other) {
4434   if (type()          != other.type()         )  return false;
4435   if (can_be_reused() != other.can_be_reused())  return false;
4436   // For floating point values we compare the bit pattern.
4437   switch (type()) {
4438   case T_INT:
4439   case T_FLOAT:   return (_v._value.i == other._v._value.i);
4440   case T_LONG:
4441   case T_DOUBLE:  return (_v._value.j == other._v._value.j);
4442   case T_OBJECT:
4443   case T_ADDRESS: return (_v._value.l == other._v._value.l);
4444   case T_VOID:    return (_v._value.l == other._v._value.l);  // jump-table entries
4445   case T_METADATA: return (_v._metadata == other._v._metadata);
4446   default: ShouldNotReachHere(); return false;
4447   }
4448 }
4449 
4450 static int type_to_size_in_bytes(BasicType t) {
4451   switch (t) {
4452   case T_INT:     return sizeof(jint   );
4453   case T_LONG:    return sizeof(jlong  );
4454   case T_FLOAT:   return sizeof(jfloat );
4455   case T_DOUBLE:  return sizeof(jdouble);
4456   case T_METADATA: return sizeof(Metadata*);
4457     // We use T_VOID as marker for jump-table entries (labels) which
4458     // need an internal word relocation.
4459   case T_VOID:
4460   case T_ADDRESS:
4461   case T_OBJECT:  return sizeof(jobject);
4462   default:
4463     ShouldNotReachHere();
4464     return -1;
4465   }
4466 }
4467 
4468 int Compile::ConstantTable::qsort_comparator(Constant* a, Constant* b) {
4469   // sort descending
4470   if (a->freq() > b->freq())  return -1;
4471   if (a->freq() < b->freq())  return  1;
4472   return 0;
4473 }
4474 
4475 void Compile::ConstantTable::calculate_offsets_and_size() {
4476   // First, sort the array by frequencies.
4477   _constants.sort(qsort_comparator);
4478 
4479 #ifdef ASSERT
4480   // Make sure all jump-table entries were sorted to the end of the
4481   // array (they have a negative frequency).
4482   bool found_void = false;
4483   for (int i = 0; i < _constants.length(); i++) {
4484     Constant con = _constants.at(i);
4485     if (con.type() == T_VOID)
4486       found_void = true;  // jump-tables
4487     else
4488       assert(!found_void, "wrong sorting");
4489   }
4490 #endif
4491 
4492   int offset = 0;
4493   for (int i = 0; i < _constants.length(); i++) {
4494     Constant* con = _constants.adr_at(i);
4495 
4496     // Align offset for type.
4497     int typesize = type_to_size_in_bytes(con->type());
4498     offset = align_up(offset, typesize);
4499     con->set_offset(offset);   // set constant's offset
4500 
4501     if (con->type() == T_VOID) {
4502       MachConstantNode* n = (MachConstantNode*) con->get_jobject();
4503       offset = offset + typesize * n->outcnt();  // expand jump-table
4504     } else {
4505       offset = offset + typesize;
4506     }
4507   }
4508 
4509   // Align size up to the next section start (which is insts; see
4510   // CodeBuffer::align_at_start).
4511   assert(_size == -1, "already set?");
4512   _size = align_up(offset, (int)CodeEntryAlignment);
4513 }
4514 
4515 void Compile::ConstantTable::emit(CodeBuffer& cb) {
4516   MacroAssembler _masm(&cb);
4517   for (int i = 0; i < _constants.length(); i++) {
4518     Constant con = _constants.at(i);
4519     address constant_addr = NULL;
4520     switch (con.type()) {
4521     case T_INT:    constant_addr = _masm.int_constant(   con.get_jint()   ); break;
4522     case T_LONG:   constant_addr = _masm.long_constant(  con.get_jlong()  ); break;
4523     case T_FLOAT:  constant_addr = _masm.float_constant( con.get_jfloat() ); break;
4524     case T_DOUBLE: constant_addr = _masm.double_constant(con.get_jdouble()); break;
4525     case T_OBJECT: {
4526       jobject obj = con.get_jobject();
4527       int oop_index = _masm.oop_recorder()->find_index(obj);
4528       constant_addr = _masm.address_constant((address) obj, oop_Relocation::spec(oop_index));
4529       break;
4530     }
4531     case T_ADDRESS: {
4532       address addr = (address) con.get_jobject();
4533       constant_addr = _masm.address_constant(addr);
4534       break;
4535     }
4536     // We use T_VOID as marker for jump-table entries (labels) which
4537     // need an internal word relocation.
4538     case T_VOID: {
4539       MachConstantNode* n = (MachConstantNode*) con.get_jobject();
4540       // Fill the jump-table with a dummy word.  The real value is
4541       // filled in later in fill_jump_table.
4542       address dummy = (address) n;
4543       constant_addr = _masm.address_constant(dummy);
4544       // Expand jump-table
4545       for (uint i = 1; i < n->outcnt(); i++) {
4546         address temp_addr = _masm.address_constant(dummy + i);
4547         assert(temp_addr, "consts section too small");
4548       }
4549       break;
4550     }
4551     case T_METADATA: {
4552       Metadata* obj = con.get_metadata();
4553       int metadata_index = _masm.oop_recorder()->find_index(obj);
4554       constant_addr = _masm.address_constant((address) obj, metadata_Relocation::spec(metadata_index));
4555       break;
4556     }
4557     default: ShouldNotReachHere();
4558     }
4559     assert(constant_addr, "consts section too small");
4560     assert((constant_addr - _masm.code()->consts()->start()) == con.offset(),
4561             "must be: %d == %d", (int) (constant_addr - _masm.code()->consts()->start()), (int)(con.offset()));
4562   }
4563 }
4564 
4565 int Compile::ConstantTable::find_offset(Constant& con) const {
4566   int idx = _constants.find(con);
4567   guarantee(idx != -1, "constant must be in constant table");
4568   int offset = _constants.at(idx).offset();
4569   guarantee(offset != -1, "constant table not emitted yet?");
4570   return offset;
4571 }
4572 
4573 void Compile::ConstantTable::add(Constant& con) {
4574   if (con.can_be_reused()) {
4575     int idx = _constants.find(con);
4576     if (idx != -1 && _constants.at(idx).can_be_reused()) {
4577       _constants.adr_at(idx)->inc_freq(con.freq());  // increase the frequency by the current value
4578       return;
4579     }
4580   }
4581   (void) _constants.append(con);
4582 }
4583 
4584 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, BasicType type, jvalue value) {
4585   Block* b = Compile::current()->cfg()->get_block_for_node(n);
4586   Constant con(type, value, b->_freq);
4587   add(con);
4588   return con;
4589 }
4590 
4591 Compile::Constant Compile::ConstantTable::add(Metadata* metadata) {
4592   Constant con(metadata);
4593   add(con);
4594   return con;
4595 }
4596 
4597 Compile::Constant Compile::ConstantTable::add(MachConstantNode* n, MachOper* oper) {
4598   jvalue value;
4599   BasicType type = oper->type()->basic_type();
4600   switch (type) {
4601   case T_LONG:    value.j = oper->constantL(); break;
4602   case T_FLOAT:   value.f = oper->constantF(); break;
4603   case T_DOUBLE:  value.d = oper->constantD(); break;
4604   case T_OBJECT:
4605   case T_ADDRESS: value.l = (jobject) oper->constant(); break;
4606   case T_METADATA: return add((Metadata*)oper->constant()); break;
4607   default: guarantee(false, "unhandled type: %s", type2name(type));
4608   }
4609   return add(n, type, value);
4610 }
4611 
4612 Compile::Constant Compile::ConstantTable::add_jump_table(MachConstantNode* n) {
4613   jvalue value;
4614   // We can use the node pointer here to identify the right jump-table
4615   // as this method is called from Compile::Fill_buffer right before
4616   // the MachNodes are emitted and the jump-table is filled (means the
4617   // MachNode pointers do not change anymore).
4618   value.l = (jobject) n;
4619   Constant con(T_VOID, value, next_jump_table_freq(), false);  // Labels of a jump-table cannot be reused.
4620   add(con);
4621   return con;
4622 }
4623 
4624 void Compile::ConstantTable::fill_jump_table(CodeBuffer& cb, MachConstantNode* n, GrowableArray<Label*> labels) const {
4625   // If called from Compile::scratch_emit_size do nothing.
4626   if (Compile::current()->in_scratch_emit_size())  return;
4627 
4628   assert(labels.is_nonempty(), "must be");
4629   assert((uint) labels.length() == n->outcnt(), "must be equal: %d == %d", labels.length(), n->outcnt());
4630 
4631   // Since MachConstantNode::constant_offset() also contains
4632   // table_base_offset() we need to subtract the table_base_offset()
4633   // to get the plain offset into the constant table.
4634   int offset = n->constant_offset() - table_base_offset();
4635 
4636   MacroAssembler _masm(&cb);
4637   address* jump_table_base = (address*) (_masm.code()->consts()->start() + offset);
4638 
4639   for (uint i = 0; i < n->outcnt(); i++) {
4640     address* constant_addr = &jump_table_base[i];
4641     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));
4642     *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
4643     cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
4644   }
4645 }
4646 
4647 //----------------------------static_subtype_check-----------------------------
4648 // Shortcut important common cases when superklass is exact:
4649 // (0) superklass is java.lang.Object (can occur in reflective code)
4650 // (1) subklass is already limited to a subtype of superklass => always ok
4651 // (2) subklass does not overlap with superklass => always fail
4652 // (3) superklass has NO subtypes and we can check with a simple compare.
4653 int Compile::static_subtype_check(ciKlass* superk, ciKlass* subk) {
4654   if (StressReflectiveCode) {
4655     return SSC_full_test;       // Let caller generate the general case.
4656   }
4657 
4658   if (superk == env()->Object_klass()) {
4659     return SSC_always_true;     // (0) this test cannot fail
4660   }
4661 
4662   ciType* superelem = superk;
4663   if (superelem->is_array_klass())
4664     superelem = superelem->as_array_klass()->base_element_type();
4665 
4666   if (!subk->is_interface()) {  // cannot trust static interface types yet
4667     if (subk->is_subtype_of(superk)) {
4668       return SSC_always_true;   // (1) false path dead; no dynamic test needed
4669     }
4670     if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
4671         !superk->is_subtype_of(subk)) {
4672       return SSC_always_false;
4673     }
4674   }
4675 
4676   // If casting to an instance klass, it must have no subtypes
4677   if (superk->is_interface()) {
4678     // Cannot trust interfaces yet.
4679     // %%% S.B. superk->nof_implementors() == 1
4680   } else if (superelem->is_instance_klass()) {
4681     ciInstanceKlass* ik = superelem->as_instance_klass();
4682     if (!ik->has_subklass() && !ik->is_interface()) {
4683       if (!ik->is_final()) {
4684         // Add a dependency if there is a chance of a later subclass.
4685         dependencies()->assert_leaf_type(ik);
4686       }
4687       return SSC_easy_test;     // (3) caller can do a simple ptr comparison
4688     }
4689   } else {
4690     // A primitive array type has no subtypes.
4691     return SSC_easy_test;       // (3) caller can do a simple ptr comparison
4692   }
4693 
4694   return SSC_full_test;
4695 }
4696 
4697 Node* Compile::conv_I2X_index(PhaseGVN* phase, Node* idx, const TypeInt* sizetype, Node* ctrl) {
4698 #ifdef _LP64
4699   // The scaled index operand to AddP must be a clean 64-bit value.
4700   // Java allows a 32-bit int to be incremented to a negative
4701   // value, which appears in a 64-bit register as a large
4702   // positive number.  Using that large positive number as an
4703   // operand in pointer arithmetic has bad consequences.
4704   // On the other hand, 32-bit overflow is rare, and the possibility
4705   // can often be excluded, if we annotate the ConvI2L node with
4706   // a type assertion that its value is known to be a small positive
4707   // number.  (The prior range check has ensured this.)
4708   // This assertion is used by ConvI2LNode::Ideal.
4709   int index_max = max_jint - 1;  // array size is max_jint, index is one less
4710   if (sizetype != NULL) index_max = sizetype->_hi - 1;
4711   const TypeInt* iidxtype = TypeInt::make(0, index_max, Type::WidenMax);
4712   idx = constrained_convI2L(phase, idx, iidxtype, ctrl);
4713 #endif
4714   return idx;
4715 }
4716 
4717 // Convert integer value to a narrowed long type dependent on ctrl (for example, a range check)
4718 Node* Compile::constrained_convI2L(PhaseGVN* phase, Node* value, const TypeInt* itype, Node* ctrl) {
4719   if (ctrl != NULL) {
4720     // Express control dependency by a CastII node with a narrow type.
4721     value = new CastIINode(value, itype, false, true /* range check dependency */);
4722     // Make the CastII node dependent on the control input to prevent the narrowed ConvI2L
4723     // node from floating above the range check during loop optimizations. Otherwise, the
4724     // ConvI2L node may be eliminated independently of the range check, causing the data path
4725     // to become TOP while the control path is still there (although it's unreachable).
4726     value->set_req(0, ctrl);
4727     // Save CastII node to remove it after loop optimizations.
4728     phase->C->add_range_check_cast(value);
4729     value = phase->transform(value);
4730   }
4731   const TypeLong* ltype = TypeLong::make(itype->_lo, itype->_hi, itype->_widen);
4732   return phase->transform(new ConvI2LNode(value, ltype));
4733 }
4734 
4735 // The message about the current inlining is accumulated in
4736 // _print_inlining_stream and transfered into the _print_inlining_list
4737 // once we know whether inlining succeeds or not. For regular
4738 // inlining, messages are appended to the buffer pointed by
4739 // _print_inlining_idx in the _print_inlining_list. For late inlining,
4740 // a new buffer is added after _print_inlining_idx in the list. This
4741 // way we can update the inlining message for late inlining call site
4742 // when the inlining is attempted again.
4743 void Compile::print_inlining_init() {
4744   if (print_inlining() || print_intrinsics()) {
4745     _print_inlining_stream = new stringStream();
4746     _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer>(comp_arena(), 1, 1, PrintInliningBuffer());
4747   }
4748 }
4749 
4750 void Compile::print_inlining_reinit() {
4751   if (print_inlining() || print_intrinsics()) {
4752     // Re allocate buffer when we change ResourceMark
4753     _print_inlining_stream = new stringStream();
4754   }
4755 }
4756 
4757 void Compile::print_inlining_reset() {
4758   _print_inlining_stream->reset();
4759 }
4760 
4761 void Compile::print_inlining_commit() {
4762   assert(print_inlining() || print_intrinsics(), "PrintInlining off?");
4763   // Transfer the message from _print_inlining_stream to the current
4764   // _print_inlining_list buffer and clear _print_inlining_stream.
4765   _print_inlining_list->at(_print_inlining_idx).ss()->write(_print_inlining_stream->as_string(), _print_inlining_stream->size());
4766   print_inlining_reset();
4767 }
4768 
4769 void Compile::print_inlining_push() {
4770   // Add new buffer to the _print_inlining_list at current position
4771   _print_inlining_idx++;
4772   _print_inlining_list->insert_before(_print_inlining_idx, PrintInliningBuffer());
4773 }
4774 
4775 Compile::PrintInliningBuffer& Compile::print_inlining_current() {
4776   return _print_inlining_list->at(_print_inlining_idx);
4777 }
4778 
4779 void Compile::print_inlining_update(CallGenerator* cg) {
4780   if (print_inlining() || print_intrinsics()) {
4781     if (!cg->is_late_inline()) {
4782       if (print_inlining_current().cg() != NULL) {
4783         print_inlining_push();
4784       }
4785       print_inlining_commit();
4786     } else {
4787       if (print_inlining_current().cg() != cg &&
4788           (print_inlining_current().cg() != NULL ||
4789            print_inlining_current().ss()->size() != 0)) {
4790         print_inlining_push();
4791       }
4792       print_inlining_commit();
4793       print_inlining_current().set_cg(cg);
4794     }
4795   }
4796 }
4797 
4798 void Compile::print_inlining_move_to(CallGenerator* cg) {
4799   // We resume inlining at a late inlining call site. Locate the
4800   // corresponding inlining buffer so that we can update it.
4801   if (print_inlining()) {
4802     for (int i = 0; i < _print_inlining_list->length(); i++) {
4803       if (_print_inlining_list->adr_at(i)->cg() == cg) {
4804         _print_inlining_idx = i;
4805         return;
4806       }
4807     }
4808     ShouldNotReachHere();
4809   }
4810 }
4811 
4812 void Compile::print_inlining_update_delayed(CallGenerator* cg) {
4813   if (print_inlining()) {
4814     assert(_print_inlining_stream->size() > 0, "missing inlining msg");
4815     assert(print_inlining_current().cg() == cg, "wrong entry");
4816     // replace message with new message
4817     _print_inlining_list->at_put(_print_inlining_idx, PrintInliningBuffer());
4818     print_inlining_commit();
4819     print_inlining_current().set_cg(cg);
4820   }
4821 }
4822 
4823 void Compile::print_inlining_assert_ready() {
4824   assert(!_print_inlining || _print_inlining_stream->size() == 0, "loosing data");
4825 }
4826 
4827 void Compile::process_print_inlining() {
4828   bool do_print_inlining = print_inlining() || print_intrinsics();
4829   if (do_print_inlining || log() != NULL) {
4830     // Print inlining message for candidates that we couldn't inline
4831     // for lack of space
4832     for (int i = 0; i < _late_inlines.length(); i++) {
4833       CallGenerator* cg = _late_inlines.at(i);
4834       if (!cg->is_mh_late_inline()) {
4835         const char* msg = "live nodes > LiveNodeCountInliningCutoff";
4836         if (do_print_inlining) {
4837           cg->print_inlining_late(msg);
4838         }
4839         log_late_inline_failure(cg, msg);
4840       }
4841     }
4842   }
4843   if (do_print_inlining) {
4844     ResourceMark rm;
4845     stringStream ss;
4846     for (int i = 0; i < _print_inlining_list->length(); i++) {
4847       ss.print("%s", _print_inlining_list->adr_at(i)->ss()->as_string());
4848     }
4849     size_t end = ss.size();
4850     _print_inlining_output = NEW_ARENA_ARRAY(comp_arena(), char, end+1);
4851     strncpy(_print_inlining_output, ss.base(), end+1);
4852     _print_inlining_output[end] = 0;
4853   }
4854 }
4855 
4856 void Compile::dump_print_inlining() {
4857   if (_print_inlining_output != NULL) {
4858     tty->print_raw(_print_inlining_output);
4859   }
4860 }
4861 
4862 void Compile::log_late_inline(CallGenerator* cg) {
4863   if (log() != NULL) {
4864     log()->head("late_inline method='%d'  inline_id='" JLONG_FORMAT "'", log()->identify(cg->method()),
4865                 cg->unique_id());
4866     JVMState* p = cg->call_node()->jvms();
4867     while (p != NULL) {
4868       log()->elem("jvms bci='%d' method='%d'", p->bci(), log()->identify(p->method()));
4869       p = p->caller();
4870     }
4871     log()->tail("late_inline");
4872   }
4873 }
4874 
4875 void Compile::log_late_inline_failure(CallGenerator* cg, const char* msg) {
4876   log_late_inline(cg);
4877   if (log() != NULL) {
4878     log()->inline_fail(msg);
4879   }
4880 }
4881 
4882 void Compile::log_inline_id(CallGenerator* cg) {
4883   if (log() != NULL) {
4884     // The LogCompilation tool needs a unique way to identify late
4885     // inline call sites. This id must be unique for this call site in
4886     // this compilation. Try to have it unique across compilations as
4887     // well because it can be convenient when grepping through the log
4888     // file.
4889     // Distinguish OSR compilations from others in case CICountOSR is
4890     // on.
4891     jlong id = ((jlong)unique()) + (((jlong)compile_id()) << 33) + (CICountOSR && is_osr_compilation() ? ((jlong)1) << 32 : 0);
4892     cg->set_unique_id(id);
4893     log()->elem("inline_id id='" JLONG_FORMAT "'", id);
4894   }
4895 }
4896 
4897 void Compile::log_inline_failure(const char* msg) {
4898   if (C->log() != NULL) {
4899     C->log()->inline_fail(msg);
4900   }
4901 }
4902 
4903 
4904 // Dump inlining replay data to the stream.
4905 // Don't change thread state and acquire any locks.
4906 void Compile::dump_inline_data(outputStream* out) {
4907   InlineTree* inl_tree = ilt();
4908   if (inl_tree != NULL) {
4909     out->print(" inline %d", inl_tree->count());
4910     inl_tree->dump_replay_data(out);
4911   }
4912 }
4913 
4914 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
4915   if (n1->Opcode() < n2->Opcode())      return -1;
4916   else if (n1->Opcode() > n2->Opcode()) return 1;
4917 
4918   assert(n1->req() == n2->req(), "can't compare %s nodes: n1->req() = %d, n2->req() = %d", NodeClassNames[n1->Opcode()], n1->req(), n2->req());
4919   for (uint i = 1; i < n1->req(); i++) {
4920     if (n1->in(i) < n2->in(i))      return -1;
4921     else if (n1->in(i) > n2->in(i)) return 1;
4922   }
4923 
4924   return 0;
4925 }
4926 
4927 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
4928   Node* n1 = *n1p;
4929   Node* n2 = *n2p;
4930 
4931   return cmp_expensive_nodes(n1, n2);
4932 }
4933 
4934 void Compile::sort_expensive_nodes() {
4935   if (!expensive_nodes_sorted()) {
4936     _expensive_nodes->sort(cmp_expensive_nodes);
4937   }
4938 }
4939 
4940 bool Compile::expensive_nodes_sorted() const {
4941   for (int i = 1; i < _expensive_nodes->length(); i++) {
4942     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i-1)) < 0) {
4943       return false;
4944     }
4945   }
4946   return true;
4947 }
4948 
4949 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
4950   if (_expensive_nodes->length() == 0) {
4951     return false;
4952   }
4953 
4954   assert(OptimizeExpensiveOps, "optimization off?");
4955 
4956   // Take this opportunity to remove dead nodes from the list
4957   int j = 0;
4958   for (int i = 0; i < _expensive_nodes->length(); i++) {
4959     Node* n = _expensive_nodes->at(i);
4960     if (!n->is_unreachable(igvn)) {
4961       assert(n->is_expensive(), "should be expensive");
4962       _expensive_nodes->at_put(j, n);
4963       j++;
4964     }
4965   }
4966   _expensive_nodes->trunc_to(j);
4967 
4968   // Then sort the list so that similar nodes are next to each other
4969   // and check for at least two nodes of identical kind with same data
4970   // inputs.
4971   sort_expensive_nodes();
4972 
4973   for (int i = 0; i < _expensive_nodes->length()-1; i++) {
4974     if (cmp_expensive_nodes(_expensive_nodes->adr_at(i), _expensive_nodes->adr_at(i+1)) == 0) {
4975       return true;
4976     }
4977   }
4978 
4979   return false;
4980 }
4981 
4982 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
4983   if (_expensive_nodes->length() == 0) {
4984     return;
4985   }
4986 
4987   assert(OptimizeExpensiveOps, "optimization off?");
4988 
4989   // Sort to bring similar nodes next to each other and clear the
4990   // control input of nodes for which there's only a single copy.
4991   sort_expensive_nodes();
4992 
4993   int j = 0;
4994   int identical = 0;
4995   int i = 0;
4996   bool modified = false;
4997   for (; i < _expensive_nodes->length()-1; i++) {
4998     assert(j <= i, "can't write beyond current index");
4999     if (_expensive_nodes->at(i)->Opcode() == _expensive_nodes->at(i+1)->Opcode()) {
5000       identical++;
5001       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
5002       continue;
5003     }
5004     if (identical > 0) {
5005       _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
5006       identical = 0;
5007     } else {
5008       Node* n = _expensive_nodes->at(i);
5009       igvn.replace_input_of(n, 0, NULL);
5010       igvn.hash_insert(n);
5011       modified = true;
5012     }
5013   }
5014   if (identical > 0) {
5015     _expensive_nodes->at_put(j++, _expensive_nodes->at(i));
5016   } else if (_expensive_nodes->length() >= 1) {
5017     Node* n = _expensive_nodes->at(i);
5018     igvn.replace_input_of(n, 0, NULL);
5019     igvn.hash_insert(n);
5020     modified = true;
5021   }
5022   _expensive_nodes->trunc_to(j);
5023   if (modified) {
5024     igvn.optimize();
5025   }
5026 }
5027 
5028 void Compile::add_expensive_node(Node * n) {
5029   assert(!_expensive_nodes->contains(n), "duplicate entry in expensive list");
5030   assert(n->is_expensive(), "expensive nodes with non-null control here only");
5031   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
5032   if (OptimizeExpensiveOps) {
5033     _expensive_nodes->append(n);
5034   } else {
5035     // Clear control input and let IGVN optimize expensive nodes if
5036     // OptimizeExpensiveOps is off.
5037     n->set_req(0, NULL);
5038   }
5039 }
5040 
5041 /**
5042  * Remove the speculative part of types and clean up the graph
5043  */
5044 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
5045   if (UseTypeSpeculation) {
5046     Unique_Node_List worklist;
5047     worklist.push(root());
5048     int modified = 0;
5049     // Go over all type nodes that carry a speculative type, drop the
5050     // speculative part of the type and enqueue the node for an igvn
5051     // which may optimize it out.
5052     for (uint next = 0; next < worklist.size(); ++next) {
5053       Node *n  = worklist.at(next);
5054       if (n->is_Type()) {
5055         TypeNode* tn = n->as_Type();
5056         const Type* t = tn->type();
5057         const Type* t_no_spec = t->remove_speculative();
5058         if (t_no_spec != t) {
5059           bool in_hash = igvn.hash_delete(n);
5060           assert(in_hash, "node should be in igvn hash table");
5061           tn->set_type(t_no_spec);
5062           igvn.hash_insert(n);
5063           igvn._worklist.push(n); // give it a chance to go away
5064           modified++;
5065         }
5066       }
5067       uint max = n->len();
5068       for( uint i = 0; i < max; ++i ) {
5069         Node *m = n->in(i);
5070         if (not_a_node(m))  continue;
5071         worklist.push(m);
5072       }
5073     }
5074     // Drop the speculative part of all types in the igvn's type table
5075     igvn.remove_speculative_types();
5076     if (modified > 0) {
5077       igvn.optimize();
5078     }
5079 #ifdef ASSERT
5080     // Verify that after the IGVN is over no speculative type has resurfaced
5081     worklist.clear();
5082     worklist.push(root());
5083     for (uint next = 0; next < worklist.size(); ++next) {
5084       Node *n  = worklist.at(next);
5085       const Type* t = igvn.type_or_null(n);
5086       assert((t == NULL) || (t == t->remove_speculative()), "no more speculative types");
5087       if (n->is_Type()) {
5088         t = n->as_Type()->type();
5089         assert(t == t->remove_speculative(), "no more speculative types");
5090       }
5091       uint max = n->len();
5092       for( uint i = 0; i < max; ++i ) {
5093         Node *m = n->in(i);
5094         if (not_a_node(m))  continue;
5095         worklist.push(m);
5096       }
5097     }
5098     igvn.check_no_speculative_types();
5099 #endif
5100   }
5101 }
5102 
5103 // Auxiliary method to support randomized stressing/fuzzing.
5104 //
5105 // This method can be called the arbitrary number of times, with current count
5106 // as the argument. The logic allows selecting a single candidate from the
5107 // running list of candidates as follows:
5108 //    int count = 0;
5109 //    Cand* selected = null;
5110 //    while(cand = cand->next()) {
5111 //      if (randomized_select(++count)) {
5112 //        selected = cand;
5113 //      }
5114 //    }
5115 //
5116 // Including count equalizes the chances any candidate is "selected".
5117 // This is useful when we don't have the complete list of candidates to choose
5118 // from uniformly. In this case, we need to adjust the randomicity of the
5119 // selection, or else we will end up biasing the selection towards the latter
5120 // candidates.
5121 //
5122 // Quick back-envelope calculation shows that for the list of n candidates
5123 // the equal probability for the candidate to persist as "best" can be
5124 // achieved by replacing it with "next" k-th candidate with the probability
5125 // of 1/k. It can be easily shown that by the end of the run, the
5126 // probability for any candidate is converged to 1/n, thus giving the
5127 // uniform distribution among all the candidates.
5128 //
5129 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
5130 #define RANDOMIZED_DOMAIN_POW 29
5131 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
5132 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
5133 bool Compile::randomized_select(int count) {
5134   assert(count > 0, "only positive");
5135   return (os::random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);
5136 }
5137 
5138 CloneMap&     Compile::clone_map()                 { return _clone_map; }
5139 void          Compile::set_clone_map(Dict* d)      { _clone_map._dict = d; }
5140 
5141 void NodeCloneInfo::dump() const {
5142   tty->print(" {%d:%d} ", idx(), gen());
5143 }
5144 
5145 void CloneMap::clone(Node* old, Node* nnn, int gen) {
5146   uint64_t val = value(old->_idx);
5147   NodeCloneInfo cio(val);
5148   assert(val != 0, "old node should be in the map");
5149   NodeCloneInfo cin(cio.idx(), gen + cio.gen());
5150   insert(nnn->_idx, cin.get());
5151 #ifndef PRODUCT
5152   if (is_debug()) {
5153     tty->print_cr("CloneMap::clone inserted node %d info {%d:%d} into CloneMap", nnn->_idx, cin.idx(), cin.gen());
5154   }
5155 #endif
5156 }
5157 
5158 void CloneMap::verify_insert_and_clone(Node* old, Node* nnn, int gen) {
5159   NodeCloneInfo cio(value(old->_idx));
5160   if (cio.get() == 0) {
5161     cio.set(old->_idx, 0);
5162     insert(old->_idx, cio.get());
5163 #ifndef PRODUCT
5164     if (is_debug()) {
5165       tty->print_cr("CloneMap::verify_insert_and_clone inserted node %d info {%d:%d} into CloneMap", old->_idx, cio.idx(), cio.gen());
5166     }
5167 #endif
5168   }
5169   clone(old, nnn, gen);
5170 }
5171 
5172 int CloneMap::max_gen() const {
5173   int g = 0;
5174   DictI di(_dict);
5175   for(; di.test(); ++di) {
5176     int t = gen(di._key);
5177     if (g < t) {
5178       g = t;
5179 #ifndef PRODUCT
5180       if (is_debug()) {
5181         tty->print_cr("CloneMap::max_gen() update max=%d from %d", g, _2_node_idx_t(di._key));
5182       }
5183 #endif
5184     }
5185   }
5186   return g;
5187 }
5188 
5189 void CloneMap::dump(node_idx_t key) const {
5190   uint64_t val = value(key);
5191   if (val != 0) {
5192     NodeCloneInfo ni(val);
5193     ni.dump();
5194   }
5195 }