1 /*
   2  * Copyright (c) 1998, 2016, 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 "memory/allocation.inline.hpp"
  27 #include "opto/block.hpp"
  28 #include "opto/c2compiler.hpp"
  29 #include "opto/callnode.hpp"
  30 #include "opto/cfgnode.hpp"
  31 #include "opto/machnode.hpp"
  32 #include "opto/runtime.hpp"
  33 #if defined AD_MD_HPP
  34 # include AD_MD_HPP
  35 #elif defined TARGET_ARCH_MODEL_x86_32
  36 # include "adfiles/ad_x86_32.hpp"
  37 #elif defined TARGET_ARCH_MODEL_x86_64
  38 # include "adfiles/ad_x86_64.hpp"
  39 #elif defined TARGET_ARCH_MODEL_sparc
  40 # include "adfiles/ad_sparc.hpp"
  41 #elif defined TARGET_ARCH_MODEL_zero
  42 # include "adfiles/ad_zero.hpp"
  43 #elif defined TARGET_ARCH_MODEL_ppc_64
  44 # include "adfiles/ad_ppc_64.hpp"
  45 #endif
  46 
  47 // Optimization - Graph Style
  48 
  49 // Check whether val is not-null-decoded compressed oop,
  50 // i.e. will grab into the base of the heap if it represents NULL.
  51 static bool accesses_heap_base_zone(Node *val) {
  52   if (Universe::narrow_oop_base() != NULL) { // Implies UseCompressedOops.
  53     if (val && val->is_Mach()) {
  54       if (val->as_Mach()->ideal_Opcode() == Op_DecodeN) {
  55         // This assumes all Decodes with TypePtr::NotNull are matched to nodes that
  56         // decode NULL to point to the heap base (Decode_NN).
  57         if (val->bottom_type()->is_oopptr()->ptr() == TypePtr::NotNull) {
  58           return true;
  59         }
  60       }
  61       // Must recognize load operation with Decode matched in memory operand.
  62       // We should not reach here exept for PPC/AIX, as os::zero_page_read_protected()
  63       // returns true everywhere else. On PPC, no such memory operands
  64       // exist, therefore we did not yet implement a check for such operands.
  65       NOT_AIX(Unimplemented());
  66     }
  67   }
  68   return false;
  69 }
  70 
  71 static bool needs_explicit_null_check_for_read(Node *val) {
  72   // On some OSes (AIX) the page at address 0 is only write protected.
  73   // If so, only Store operations will trap.
  74   if (os::zero_page_read_protected()) {
  75     return false;  // Implicit null check will work.
  76   }
  77   // Also a read accessing the base of a heap-based compressed heap will trap.
  78   if (accesses_heap_base_zone(val) &&                    // Hits the base zone page.
  79       Universe::narrow_oop_use_implicit_null_checks()) { // Base zone page is protected.
  80     return false;
  81   }
  82 
  83   return true;
  84 }
  85 
  86 //------------------------------implicit_null_check----------------------------
  87 // Detect implicit-null-check opportunities.  Basically, find NULL checks
  88 // with suitable memory ops nearby.  Use the memory op to do the NULL check.
  89 // I can generate a memory op if there is not one nearby.
  90 // The proj is the control projection for the not-null case.
  91 // The val is the pointer being checked for nullness or
  92 // decodeHeapOop_not_null node if it did not fold into address.
  93 void PhaseCFG::implicit_null_check(Block* block, Node *proj, Node *val, int allowed_reasons) {
  94   // Assume if null check need for 0 offset then always needed
  95   // Intel solaris doesn't support any null checks yet and no
  96   // mechanism exists (yet) to set the switches at an os_cpu level
  97   if( !ImplicitNullChecks || MacroAssembler::needs_explicit_null_check(0)) return;
  98 
  99   // Make sure the ptr-is-null path appears to be uncommon!
 100   float f = block->end()->as_MachIf()->_prob;
 101   if( proj->Opcode() == Op_IfTrue ) f = 1.0f - f;
 102   if( f > PROB_UNLIKELY_MAG(4) ) return;
 103 
 104   uint bidx = 0;                // Capture index of value into memop
 105   bool was_store;               // Memory op is a store op
 106 
 107   // Get the successor block for if the test ptr is non-null
 108   Block* not_null_block;  // this one goes with the proj
 109   Block* null_block;
 110   if (block->get_node(block->number_of_nodes()-1) == proj) {
 111     null_block     = block->_succs[0];
 112     not_null_block = block->_succs[1];
 113   } else {
 114     assert(block->get_node(block->number_of_nodes()-2) == proj, "proj is one or the other");
 115     not_null_block = block->_succs[0];
 116     null_block     = block->_succs[1];
 117   }
 118   while (null_block->is_Empty() == Block::empty_with_goto) {
 119     null_block     = null_block->_succs[0];
 120   }
 121 
 122   // Search the exception block for an uncommon trap.
 123   // (See Parse::do_if and Parse::do_ifnull for the reason
 124   // we need an uncommon trap.  Briefly, we need a way to
 125   // detect failure of this optimization, as in 6366351.)
 126   {
 127     bool found_trap = false;
 128     for (uint i1 = 0; i1 < null_block->number_of_nodes(); i1++) {
 129       Node* nn = null_block->get_node(i1);
 130       if (nn->is_MachCall() &&
 131           nn->as_MachCall()->entry_point() == SharedRuntime::uncommon_trap_blob()->entry_point()) {
 132         const Type* trtype = nn->in(TypeFunc::Parms)->bottom_type();
 133         if (trtype->isa_int() && trtype->is_int()->is_con()) {
 134           jint tr_con = trtype->is_int()->get_con();
 135           Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(tr_con);
 136           Deoptimization::DeoptAction action = Deoptimization::trap_request_action(tr_con);
 137           assert((int)reason < (int)BitsPerInt, "recode bit map");
 138           if (is_set_nth_bit(allowed_reasons, (int) reason)
 139               && action != Deoptimization::Action_none) {
 140             // This uncommon trap is sure to recompile, eventually.
 141             // When that happens, C->too_many_traps will prevent
 142             // this transformation from happening again.
 143             found_trap = true;
 144           }
 145         }
 146         break;
 147       }
 148     }
 149     if (!found_trap) {
 150       // We did not find an uncommon trap.
 151       return;
 152     }
 153   }
 154 
 155   // Check for decodeHeapOop_not_null node which did not fold into address
 156   bool is_decoden = ((intptr_t)val) & 1;
 157   val = (Node*)(((intptr_t)val) & ~1);
 158 
 159   assert(!is_decoden || (val->in(0) == NULL) && val->is_Mach() &&
 160          (val->as_Mach()->ideal_Opcode() == Op_DecodeN), "sanity");
 161 
 162   // Search the successor block for a load or store who's base value is also
 163   // the tested value.  There may be several.
 164   Node_List *out = new Node_List(Thread::current()->resource_area());
 165   MachNode *best = NULL;        // Best found so far
 166   for (DUIterator i = val->outs(); val->has_out(i); i++) {
 167     Node *m = val->out(i);
 168     if( !m->is_Mach() ) continue;
 169     MachNode *mach = m->as_Mach();
 170     was_store = false;
 171     int iop = mach->ideal_Opcode();
 172     switch( iop ) {
 173     case Op_LoadB:
 174     case Op_LoadUB:
 175     case Op_LoadUS:
 176     case Op_LoadD:
 177     case Op_LoadF:
 178     case Op_LoadI:
 179     case Op_LoadL:
 180     case Op_LoadP:
 181     case Op_LoadN:
 182     case Op_LoadS:
 183     case Op_LoadKlass:
 184     case Op_LoadNKlass:
 185     case Op_LoadRange:
 186     case Op_LoadD_unaligned:
 187     case Op_LoadL_unaligned:
 188       assert(mach->in(2) == val, "should be address");
 189       break;
 190     case Op_StoreB:
 191     case Op_StoreC:
 192     case Op_StoreCM:
 193     case Op_StoreD:
 194     case Op_StoreF:
 195     case Op_StoreI:
 196     case Op_StoreL:
 197     case Op_StoreP:
 198     case Op_StoreN:
 199     case Op_StoreNKlass:
 200       was_store = true;         // Memory op is a store op
 201       // Stores will have their address in slot 2 (memory in slot 1).
 202       // If the value being nul-checked is in another slot, it means we
 203       // are storing the checked value, which does NOT check the value!
 204       if( mach->in(2) != val ) continue;
 205       break;                    // Found a memory op?
 206     case Op_StrComp:
 207     case Op_StrEquals:
 208     case Op_StrIndexOf:
 209     case Op_AryEq:
 210     case Op_EncodeISOArray:
 211       // Not a legit memory op for implicit null check regardless of
 212       // embedded loads
 213       continue;
 214     default:                    // Also check for embedded loads
 215       if( !mach->needs_anti_dependence_check() )
 216         continue;               // Not an memory op; skip it
 217       if( must_clone[iop] ) {
 218         // Do not move nodes which produce flags because
 219         // RA will try to clone it to place near branch and
 220         // it will cause recompilation, see clone_node().
 221         continue;
 222       }
 223       {
 224         // Check that value is used in memory address in
 225         // instructions with embedded load (CmpP val1,(val2+off)).
 226         Node* base;
 227         Node* index;
 228         const MachOper* oper = mach->memory_inputs(base, index);
 229         if (oper == NULL || oper == (MachOper*)-1) {
 230           continue;             // Not an memory op; skip it
 231         }
 232         if (val == base ||
 233             val == index && val->bottom_type()->isa_narrowoop()) {
 234           break;                // Found it
 235         } else {
 236           continue;             // Skip it
 237         }
 238       }
 239       break;
 240     }
 241 
 242     // On some OSes (AIX) the page at address 0 is only write protected.
 243     // If so, only Store operations will trap.
 244     // But a read accessing the base of a heap-based compressed heap will trap.
 245     if (!was_store && needs_explicit_null_check_for_read(val)) {
 246       continue;
 247     }
 248 
 249     // Check that node's control edge is not-null block's head or dominates it,
 250     // otherwise we can't hoist it because there are other control dependencies.
 251     Node* ctrl = mach->in(0);
 252     if (ctrl != NULL && !(ctrl == not_null_block->head() ||
 253         get_block_for_node(ctrl)->dominates(not_null_block))) {
 254       continue;
 255     }
 256 
 257     // check if the offset is not too high for implicit exception
 258     {
 259       intptr_t offset = 0;
 260       const TypePtr *adr_type = NULL;  // Do not need this return value here
 261       const Node* base = mach->get_base_and_disp(offset, adr_type);
 262       if (base == NULL || base == NodeSentinel) {
 263         // Narrow oop address doesn't have base, only index
 264         if( val->bottom_type()->isa_narrowoop() &&
 265             MacroAssembler::needs_explicit_null_check(offset) )
 266           continue;             // Give up if offset is beyond page size
 267         // cannot reason about it; is probably not implicit null exception
 268       } else {
 269         const TypePtr* tptr;
 270         if (UseCompressedOops && (Universe::narrow_oop_shift() == 0 ||
 271                                   Universe::narrow_klass_shift() == 0)) {
 272           // 32-bits narrow oop can be the base of address expressions
 273           tptr = base->get_ptr_type();
 274         } else {
 275           // only regular oops are expected here
 276           tptr = base->bottom_type()->is_ptr();
 277         }
 278         // Give up if offset is not a compile-time constant
 279         if( offset == Type::OffsetBot || tptr->_offset == Type::OffsetBot )
 280           continue;
 281         offset += tptr->_offset; // correct if base is offseted
 282         if( MacroAssembler::needs_explicit_null_check(offset) )
 283           continue;             // Give up is reference is beyond 4K page size
 284       }
 285     }
 286 
 287     // Check ctrl input to see if the null-check dominates the memory op
 288     Block *cb = get_block_for_node(mach);
 289     cb = cb->_idom;             // Always hoist at least 1 block
 290     if( !was_store ) {          // Stores can be hoisted only one block
 291       while( cb->_dom_depth > (block->_dom_depth + 1))
 292         cb = cb->_idom;         // Hoist loads as far as we want
 293       // The non-null-block should dominate the memory op, too. Live
 294       // range spilling will insert a spill in the non-null-block if it is
 295       // needs to spill the memory op for an implicit null check.
 296       if (cb->_dom_depth == (block->_dom_depth + 1)) {
 297         if (cb != not_null_block) continue;
 298         cb = cb->_idom;
 299       }
 300     }
 301     if( cb != block ) continue;
 302 
 303     // Found a memory user; see if it can be hoisted to check-block
 304     uint vidx = 0;              // Capture index of value into memop
 305     uint j;
 306     for( j = mach->req()-1; j > 0; j-- ) {
 307       if( mach->in(j) == val ) {
 308         vidx = j;
 309         // Ignore DecodeN val which could be hoisted to where needed.
 310         if( is_decoden ) continue;
 311       }
 312       // Block of memory-op input
 313       Block *inb = get_block_for_node(mach->in(j));
 314       Block *b = block;          // Start from nul check
 315       while( b != inb && b->_dom_depth > inb->_dom_depth )
 316         b = b->_idom;           // search upwards for input
 317       // See if input dominates null check
 318       if( b != inb )
 319         break;
 320     }
 321     if( j > 0 )
 322       continue;
 323     Block *mb = get_block_for_node(mach);
 324     // Hoisting stores requires more checks for the anti-dependence case.
 325     // Give up hoisting if we have to move the store past any load.
 326     if( was_store ) {
 327       Block *b = mb;            // Start searching here for a local load
 328       // mach use (faulting) trying to hoist
 329       // n might be blocker to hoisting
 330       while( b != block ) {
 331         uint k;
 332         for( k = 1; k < b->number_of_nodes(); k++ ) {
 333           Node *n = b->get_node(k);
 334           if( n->needs_anti_dependence_check() &&
 335               n->in(LoadNode::Memory) == mach->in(StoreNode::Memory) )
 336             break;              // Found anti-dependent load
 337         }
 338         if( k < b->number_of_nodes() )
 339           break;                // Found anti-dependent load
 340         // Make sure control does not do a merge (would have to check allpaths)
 341         if( b->num_preds() != 2 ) break;
 342         b = get_block_for_node(b->pred(1)); // Move up to predecessor block
 343       }
 344       if( b != block ) continue;
 345     }
 346 
 347     // Make sure this memory op is not already being used for a NullCheck
 348     Node *e = mb->end();
 349     if( e->is_MachNullCheck() && e->in(1) == mach )
 350       continue;                 // Already being used as a NULL check
 351 
 352     // Found a candidate!  Pick one with least dom depth - the highest
 353     // in the dom tree should be closest to the null check.
 354     if (best == NULL || get_block_for_node(mach)->_dom_depth < get_block_for_node(best)->_dom_depth) {
 355       best = mach;
 356       bidx = vidx;
 357     }
 358   }
 359   // No candidate!
 360   if (best == NULL) {
 361     return;
 362   }
 363 
 364   // ---- Found an implicit null check
 365   extern int implicit_null_checks;
 366   implicit_null_checks++;
 367 
 368   if( is_decoden ) {
 369     // Check if we need to hoist decodeHeapOop_not_null first.
 370     Block *valb = get_block_for_node(val);
 371     if( block != valb && block->_dom_depth < valb->_dom_depth ) {
 372       // Hoist it up to the end of the test block.
 373       valb->find_remove(val);
 374       block->add_inst(val);
 375       map_node_to_block(val, block);
 376       // DecodeN on x86 may kill flags. Check for flag-killing projections
 377       // that also need to be hoisted.
 378       for (DUIterator_Fast jmax, j = val->fast_outs(jmax); j < jmax; j++) {
 379         Node* n = val->fast_out(j);
 380         if( n->is_MachProj() ) {
 381           get_block_for_node(n)->find_remove(n);
 382           block->add_inst(n);
 383           map_node_to_block(n, block);
 384         }
 385       }
 386     }
 387   }
 388   // Hoist the memory candidate up to the end of the test block.
 389   Block *old_block = get_block_for_node(best);
 390   old_block->find_remove(best);
 391   block->add_inst(best);
 392   map_node_to_block(best, block);
 393 
 394   // Move the control dependence if it is pinned to not-null block.
 395   // Don't change it in other cases: NULL or dominating control.
 396   if (best->in(0) == not_null_block->head()) {
 397     // Set it to control edge of null check.
 398     best->set_req(0, proj->in(0)->in(0));
 399   }
 400 
 401   // Check for flag-killing projections that also need to be hoisted
 402   // Should be DU safe because no edge updates.
 403   for (DUIterator_Fast jmax, j = best->fast_outs(jmax); j < jmax; j++) {
 404     Node* n = best->fast_out(j);
 405     if( n->is_MachProj() ) {
 406       get_block_for_node(n)->find_remove(n);
 407       block->add_inst(n);
 408       map_node_to_block(n, block);
 409     }
 410   }
 411 
 412   // proj==Op_True --> ne test; proj==Op_False --> eq test.
 413   // One of two graph shapes got matched:
 414   //   (IfTrue  (If (Bool NE (CmpP ptr NULL))))
 415   //   (IfFalse (If (Bool EQ (CmpP ptr NULL))))
 416   // NULL checks are always branch-if-eq.  If we see a IfTrue projection
 417   // then we are replacing a 'ne' test with a 'eq' NULL check test.
 418   // We need to flip the projections to keep the same semantics.
 419   if( proj->Opcode() == Op_IfTrue ) {
 420     // Swap order of projections in basic block to swap branch targets
 421     Node *tmp1 = block->get_node(block->end_idx()+1);
 422     Node *tmp2 = block->get_node(block->end_idx()+2);
 423     block->map_node(tmp2, block->end_idx()+1);
 424     block->map_node(tmp1, block->end_idx()+2);
 425     Node *tmp = new (C) Node(C->top()); // Use not NULL input
 426     tmp1->replace_by(tmp);
 427     tmp2->replace_by(tmp1);
 428     tmp->replace_by(tmp2);
 429     tmp->destruct();
 430   }
 431 
 432   // Remove the existing null check; use a new implicit null check instead.
 433   // Since schedule-local needs precise def-use info, we need to correct
 434   // it as well.
 435   Node *old_tst = proj->in(0);
 436   MachNode *nul_chk = new (C) MachNullCheckNode(old_tst->in(0),best,bidx);
 437   block->map_node(nul_chk, block->end_idx());
 438   map_node_to_block(nul_chk, block);
 439   // Redirect users of old_test to nul_chk
 440   for (DUIterator_Last i2min, i2 = old_tst->last_outs(i2min); i2 >= i2min; --i2)
 441     old_tst->last_out(i2)->set_req(0, nul_chk);
 442   // Clean-up any dead code
 443   for (uint i3 = 0; i3 < old_tst->req(); i3++) {
 444     Node* in = old_tst->in(i3);
 445     old_tst->set_req(i3, NULL);
 446     if (in->outcnt() == 0) {
 447       // Remove dead input node
 448       in->disconnect_inputs(NULL, C);
 449       block->find_remove(in);
 450     }
 451   }
 452 
 453   latency_from_uses(nul_chk);
 454   latency_from_uses(best);
 455 
 456   // insert anti-dependences to defs in this block
 457   if (! best->needs_anti_dependence_check()) {
 458     for (uint k = 1; k < block->number_of_nodes(); k++) {
 459       Node *n = block->get_node(k);
 460       if (n->needs_anti_dependence_check() &&
 461           n->in(LoadNode::Memory) == best->in(StoreNode::Memory)) {
 462         // Found anti-dependent load
 463         insert_anti_dependences(block, n);
 464       }
 465     }
 466   }
 467 }
 468 
 469 
 470 //------------------------------select-----------------------------------------
 471 // Select a nice fellow from the worklist to schedule next. If there is only
 472 // one choice, then use it. Projections take top priority for correctness
 473 // reasons - if I see a projection, then it is next.  There are a number of
 474 // other special cases, for instructions that consume condition codes, et al.
 475 // These are chosen immediately. Some instructions are required to immediately
 476 // precede the last instruction in the block, and these are taken last. Of the
 477 // remaining cases (most), choose the instruction with the greatest latency
 478 // (that is, the most number of pseudo-cycles required to the end of the
 479 // routine). If there is a tie, choose the instruction with the most inputs.
 480 Node* PhaseCFG::select(Block* block, Node_List &worklist, GrowableArray<int> &ready_cnt, VectorSet &next_call, uint sched_slot) {
 481 
 482   // If only a single entry on the stack, use it
 483   uint cnt = worklist.size();
 484   if (cnt == 1) {
 485     Node *n = worklist[0];
 486     worklist.map(0,worklist.pop());
 487     return n;
 488   }
 489 
 490   uint choice  = 0; // Bigger is most important
 491   uint latency = 0; // Bigger is scheduled first
 492   uint score   = 0; // Bigger is better
 493   int idx = -1;     // Index in worklist
 494   int cand_cnt = 0; // Candidate count
 495 
 496   for( uint i=0; i<cnt; i++ ) { // Inspect entire worklist
 497     // Order in worklist is used to break ties.
 498     // See caller for how this is used to delay scheduling
 499     // of induction variable increments to after the other
 500     // uses of the phi are scheduled.
 501     Node *n = worklist[i];      // Get Node on worklist
 502 
 503     int iop = n->is_Mach() ? n->as_Mach()->ideal_Opcode() : 0;
 504     if( n->is_Proj() ||         // Projections always win
 505         n->Opcode()== Op_Con || // So does constant 'Top'
 506         iop == Op_CreateEx ||   // Create-exception must start block
 507         iop == Op_CheckCastPP
 508         ) {
 509       worklist.map(i,worklist.pop());
 510       return n;
 511     }
 512 
 513     // Final call in a block must be adjacent to 'catch'
 514     Node *e = block->end();
 515     if( e->is_Catch() && e->in(0)->in(0) == n )
 516       continue;
 517 
 518     // Memory op for an implicit null check has to be at the end of the block
 519     if( e->is_MachNullCheck() && e->in(1) == n )
 520       continue;
 521 
 522     // Schedule IV increment last.
 523     if (e->is_Mach() && e->as_Mach()->ideal_Opcode() == Op_CountedLoopEnd &&
 524         e->in(1)->in(1) == n && n->is_iteratively_computed())
 525       continue;
 526 
 527     uint n_choice  = 2;
 528 
 529     // See if this instruction is consumed by a branch. If so, then (as the
 530     // branch is the last instruction in the basic block) force it to the
 531     // end of the basic block
 532     if ( must_clone[iop] ) {
 533       // See if any use is a branch
 534       bool found_machif = false;
 535 
 536       for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
 537         Node* use = n->fast_out(j);
 538 
 539         // The use is a conditional branch, make them adjacent
 540         if (use->is_MachIf() && get_block_for_node(use) == block) {
 541           found_machif = true;
 542           break;
 543         }
 544 
 545         // More than this instruction pending for successor to be ready,
 546         // don't choose this if other opportunities are ready
 547         if (ready_cnt.at(use->_idx) > 1)
 548           n_choice = 1;
 549       }
 550 
 551       // loop terminated, prefer not to use this instruction
 552       if (found_machif)
 553         continue;
 554     }
 555 
 556     // See if this has a predecessor that is "must_clone", i.e. sets the
 557     // condition code. If so, choose this first
 558     for (uint j = 0; j < n->req() ; j++) {
 559       Node *inn = n->in(j);
 560       if (inn) {
 561         if (inn->is_Mach() && must_clone[inn->as_Mach()->ideal_Opcode()] ) {
 562           n_choice = 3;
 563           break;
 564         }
 565       }
 566     }
 567 
 568     // MachTemps should be scheduled last so they are near their uses
 569     if (n->is_MachTemp()) {
 570       n_choice = 1;
 571     }
 572 
 573     uint n_latency = get_latency_for_node(n);
 574     uint n_score   = n->req();   // Many inputs get high score to break ties
 575 
 576     // Keep best latency found
 577     cand_cnt++;
 578     if (choice < n_choice ||
 579         (choice == n_choice &&
 580          ((StressLCM && Compile::randomized_select(cand_cnt)) ||
 581           (!StressLCM &&
 582            (latency < n_latency ||
 583             (latency == n_latency &&
 584              (score < n_score))))))) {
 585       choice  = n_choice;
 586       latency = n_latency;
 587       score   = n_score;
 588       idx     = i;               // Also keep index in worklist
 589     }
 590   } // End of for all ready nodes in worklist
 591 
 592   assert(idx >= 0, "index should be set");
 593   Node *n = worklist[(uint)idx];      // Get the winner
 594 
 595   worklist.map((uint)idx, worklist.pop());     // Compress worklist
 596   return n;
 597 }
 598 
 599 
 600 //------------------------------set_next_call----------------------------------
 601 void PhaseCFG::set_next_call(Block* block, Node* n, VectorSet& next_call) {
 602   if( next_call.test_set(n->_idx) ) return;
 603   for( uint i=0; i<n->len(); i++ ) {
 604     Node *m = n->in(i);
 605     if( !m ) continue;  // must see all nodes in block that precede call
 606     if (get_block_for_node(m) == block) {
 607       set_next_call(block, m, next_call);
 608     }
 609   }
 610 }
 611 
 612 //------------------------------needed_for_next_call---------------------------
 613 // Set the flag 'next_call' for each Node that is needed for the next call to
 614 // be scheduled.  This flag lets me bias scheduling so Nodes needed for the
 615 // next subroutine call get priority - basically it moves things NOT needed
 616 // for the next call till after the call.  This prevents me from trying to
 617 // carry lots of stuff live across a call.
 618 void PhaseCFG::needed_for_next_call(Block* block, Node* this_call, VectorSet& next_call) {
 619   // Find the next control-defining Node in this block
 620   Node* call = NULL;
 621   for (DUIterator_Fast imax, i = this_call->fast_outs(imax); i < imax; i++) {
 622     Node* m = this_call->fast_out(i);
 623     if (get_block_for_node(m) == block && // Local-block user
 624         m != this_call &&       // Not self-start node
 625         m->is_MachCall()) {
 626       call = m;
 627       break;
 628     }
 629   }
 630   if (call == NULL)  return;    // No next call (e.g., block end is near)
 631   // Set next-call for all inputs to this call
 632   set_next_call(block, call, next_call);
 633 }
 634 
 635 //------------------------------add_call_kills-------------------------------------
 636 // helper function that adds caller save registers to MachProjNode
 637 static void add_call_kills(MachProjNode *proj, RegMask& regs, const char* save_policy, bool exclude_soe) {
 638   // Fill in the kill mask for the call
 639   for( OptoReg::Name r = OptoReg::Name(0); r < _last_Mach_Reg; r=OptoReg::add(r,1) ) {
 640     if( !regs.Member(r) ) {     // Not already defined by the call
 641       // Save-on-call register?
 642       if ((save_policy[r] == 'C') ||
 643           (save_policy[r] == 'A') ||
 644           ((save_policy[r] == 'E') && exclude_soe)) {
 645         proj->_rout.Insert(r);
 646       }
 647     }
 648   }
 649 }
 650 
 651 
 652 //------------------------------sched_call-------------------------------------
 653 uint PhaseCFG::sched_call(Block* block, uint node_cnt, Node_List& worklist, GrowableArray<int>& ready_cnt, MachCallNode* mcall, VectorSet& next_call) {
 654   RegMask regs;
 655 
 656   // Schedule all the users of the call right now.  All the users are
 657   // projection Nodes, so they must be scheduled next to the call.
 658   // Collect all the defined registers.
 659   for (DUIterator_Fast imax, i = mcall->fast_outs(imax); i < imax; i++) {
 660     Node* n = mcall->fast_out(i);
 661     assert( n->is_MachProj(), "" );
 662     int n_cnt = ready_cnt.at(n->_idx)-1;
 663     ready_cnt.at_put(n->_idx, n_cnt);
 664     assert( n_cnt == 0, "" );
 665     // Schedule next to call
 666     block->map_node(n, node_cnt++);
 667     // Collect defined registers
 668     regs.OR(n->out_RegMask());
 669     // Check for scheduling the next control-definer
 670     if( n->bottom_type() == Type::CONTROL )
 671       // Warm up next pile of heuristic bits
 672       needed_for_next_call(block, n, next_call);
 673 
 674     // Children of projections are now all ready
 675     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
 676       Node* m = n->fast_out(j); // Get user
 677       if(get_block_for_node(m) != block) {
 678         continue;
 679       }
 680       if( m->is_Phi() ) continue;
 681       int m_cnt = ready_cnt.at(m->_idx)-1;
 682       ready_cnt.at_put(m->_idx, m_cnt);
 683       if( m_cnt == 0 )
 684         worklist.push(m);
 685     }
 686 
 687   }
 688 
 689   // Act as if the call defines the Frame Pointer.
 690   // Certainly the FP is alive and well after the call.
 691   regs.Insert(_matcher.c_frame_pointer());
 692 
 693   // Set all registers killed and not already defined by the call.
 694   uint r_cnt = mcall->tf()->range()->cnt();
 695   int op = mcall->ideal_Opcode();
 696   MachProjNode *proj = new (C) MachProjNode( mcall, r_cnt+1, RegMask::Empty, MachProjNode::fat_proj );
 697   map_node_to_block(proj, block);
 698   block->insert_node(proj, node_cnt++);
 699 
 700   // Select the right register save policy.
 701   const char *save_policy = NULL;
 702   switch (op) {
 703     case Op_CallRuntime:
 704     case Op_CallLeaf:
 705     case Op_CallLeafNoFP:
 706       // Calling C code so use C calling convention
 707       save_policy = _matcher._c_reg_save_policy;
 708       break;
 709 
 710     case Op_CallStaticJava:
 711     case Op_CallDynamicJava:
 712       // Calling Java code so use Java calling convention
 713       save_policy = _matcher._register_save_policy;
 714       break;
 715 
 716     default:
 717       ShouldNotReachHere();
 718   }
 719 
 720   // When using CallRuntime mark SOE registers as killed by the call
 721   // so values that could show up in the RegisterMap aren't live in a
 722   // callee saved register since the register wouldn't know where to
 723   // find them.  CallLeaf and CallLeafNoFP are ok because they can't
 724   // have debug info on them.  Strictly speaking this only needs to be
 725   // done for oops since idealreg2debugmask takes care of debug info
 726   // references but there no way to handle oops differently than other
 727   // pointers as far as the kill mask goes.
 728   bool exclude_soe = op == Op_CallRuntime;
 729 
 730   // If the call is a MethodHandle invoke, we need to exclude the
 731   // register which is used to save the SP value over MH invokes from
 732   // the mask.  Otherwise this register could be used for
 733   // deoptimization information.
 734   if (op == Op_CallStaticJava) {
 735     MachCallStaticJavaNode* mcallstaticjava = (MachCallStaticJavaNode*) mcall;
 736     if (mcallstaticjava->_method_handle_invoke)
 737       proj->_rout.OR(Matcher::method_handle_invoke_SP_save_mask());
 738   }
 739 
 740   add_call_kills(proj, regs, save_policy, exclude_soe);
 741 
 742   return node_cnt;
 743 }
 744 
 745 
 746 //------------------------------schedule_local---------------------------------
 747 // Topological sort within a block.  Someday become a real scheduler.
 748 bool PhaseCFG::schedule_local(Block* block, GrowableArray<int>& ready_cnt, VectorSet& next_call) {
 749   // Already "sorted" are the block start Node (as the first entry), and
 750   // the block-ending Node and any trailing control projections.  We leave
 751   // these alone.  PhiNodes and ParmNodes are made to follow the block start
 752   // Node.  Everything else gets topo-sorted.
 753 
 754 #ifndef PRODUCT
 755     if (trace_opto_pipelining()) {
 756       tty->print_cr("# --- schedule_local B%d, before: ---", block->_pre_order);
 757       for (uint i = 0;i < block->number_of_nodes(); i++) {
 758         tty->print("# ");
 759         block->get_node(i)->fast_dump();
 760       }
 761       tty->print_cr("#");
 762     }
 763 #endif
 764 
 765   // RootNode is already sorted
 766   if (block->number_of_nodes() == 1) {
 767     return true;
 768   }
 769 
 770   // Move PhiNodes and ParmNodes from 1 to cnt up to the start
 771   uint node_cnt = block->end_idx();
 772   uint phi_cnt = 1;
 773   uint i;
 774   for( i = 1; i<node_cnt; i++ ) { // Scan for Phi
 775     Node *n = block->get_node(i);
 776     if( n->is_Phi() ||          // Found a PhiNode or ParmNode
 777         (n->is_Proj()  && n->in(0) == block->head()) ) {
 778       // Move guy at 'phi_cnt' to the end; makes a hole at phi_cnt
 779       block->map_node(block->get_node(phi_cnt), i);
 780       block->map_node(n, phi_cnt++);  // swap Phi/Parm up front
 781     } else {                    // All others
 782       // Count block-local inputs to 'n'
 783       uint cnt = n->len();      // Input count
 784       uint local = 0;
 785       for( uint j=0; j<cnt; j++ ) {
 786         Node *m = n->in(j);
 787         if( m && get_block_for_node(m) == block && !m->is_top() )
 788           local++;              // One more block-local input
 789       }
 790       ready_cnt.at_put(n->_idx, local); // Count em up
 791 
 792 #ifdef ASSERT
 793       if( UseConcMarkSweepGC || UseG1GC ) {
 794         if( n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_StoreCM ) {
 795           // Check the precedence edges
 796           for (uint prec = n->req(); prec < n->len(); prec++) {
 797             Node* oop_store = n->in(prec);
 798             if (oop_store != NULL) {
 799               assert(get_block_for_node(oop_store)->_dom_depth <= block->_dom_depth, "oop_store must dominate card-mark");
 800             }
 801           }
 802         }
 803       }
 804 #endif
 805 
 806       // A few node types require changing a required edge to a precedence edge
 807       // before allocation.
 808       if( n->is_Mach() && n->req() > TypeFunc::Parms &&
 809           (n->as_Mach()->ideal_Opcode() == Op_MemBarAcquire ||
 810            n->as_Mach()->ideal_Opcode() == Op_MemBarVolatile) ) {
 811         // MemBarAcquire could be created without Precedent edge.
 812         // del_req() replaces the specified edge with the last input edge
 813         // and then removes the last edge. If the specified edge > number of
 814         // edges the last edge will be moved outside of the input edges array
 815         // and the edge will be lost. This is why this code should be
 816         // executed only when Precedent (== TypeFunc::Parms) edge is present.
 817         Node *x = n->in(TypeFunc::Parms);
 818         if (x != NULL && get_block_for_node(x) == block && n->find_prec_edge(x) != -1) {
 819           // Old edge to node within same block will get removed, but no precedence
 820           // edge will get added because it already exists. Update ready count.
 821           int cnt = ready_cnt.at(n->_idx);
 822           assert(cnt > 1, err_msg("MemBar node %d must not get ready here", n->_idx));
 823           ready_cnt.at_put(n->_idx, cnt-1);
 824         }
 825         n->del_req(TypeFunc::Parms);
 826         n->add_prec(x);
 827       }
 828     }
 829   }
 830   for(uint i2=i; i2< block->number_of_nodes(); i2++ ) // Trailing guys get zapped count
 831     ready_cnt.at_put(block->get_node(i2)->_idx, 0);
 832 
 833   // All the prescheduled guys do not hold back internal nodes
 834   uint i3;
 835   for(i3 = 0; i3<phi_cnt; i3++ ) {  // For all pre-scheduled
 836     Node *n = block->get_node(i3);       // Get pre-scheduled
 837     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
 838       Node* m = n->fast_out(j);
 839       if (get_block_for_node(m) == block) { // Local-block user
 840         int m_cnt = ready_cnt.at(m->_idx)-1;
 841         ready_cnt.at_put(m->_idx, m_cnt);   // Fix ready count
 842       }
 843     }
 844   }
 845 
 846   Node_List delay;
 847   // Make a worklist
 848   Node_List worklist;
 849   for(uint i4=i3; i4<node_cnt; i4++ ) {    // Put ready guys on worklist
 850     Node *m = block->get_node(i4);
 851     if( !ready_cnt.at(m->_idx) ) {   // Zero ready count?
 852       if (m->is_iteratively_computed()) {
 853         // Push induction variable increments last to allow other uses
 854         // of the phi to be scheduled first. The select() method breaks
 855         // ties in scheduling by worklist order.
 856         delay.push(m);
 857       } else if (m->is_Mach() && m->as_Mach()->ideal_Opcode() == Op_CreateEx) {
 858         // Force the CreateEx to the top of the list so it's processed
 859         // first and ends up at the start of the block.
 860         worklist.insert(0, m);
 861       } else {
 862         worklist.push(m);         // Then on to worklist!
 863       }
 864     }
 865   }
 866   while (delay.size()) {
 867     Node* d = delay.pop();
 868     worklist.push(d);
 869   }
 870 
 871   // Warm up the 'next_call' heuristic bits
 872   needed_for_next_call(block, block->head(), next_call);
 873 
 874 #ifndef PRODUCT
 875     if (trace_opto_pipelining()) {
 876       for (uint j=0; j< block->number_of_nodes(); j++) {
 877         Node     *n = block->get_node(j);
 878         int     idx = n->_idx;
 879         tty->print("#   ready cnt:%3d  ", ready_cnt.at(idx));
 880         tty->print("latency:%3d  ", get_latency_for_node(n));
 881         tty->print("%4d: %s\n", idx, n->Name());
 882       }
 883     }
 884 #endif
 885 
 886   uint max_idx = (uint)ready_cnt.length();
 887   // Pull from worklist and schedule
 888   while( worklist.size() ) {    // Worklist is not ready
 889 
 890 #ifndef PRODUCT
 891     if (trace_opto_pipelining()) {
 892       tty->print("#   ready list:");
 893       for( uint i=0; i<worklist.size(); i++ ) { // Inspect entire worklist
 894         Node *n = worklist[i];      // Get Node on worklist
 895         tty->print(" %d", n->_idx);
 896       }
 897       tty->cr();
 898     }
 899 #endif
 900 
 901     // Select and pop a ready guy from worklist
 902     Node* n = select(block, worklist, ready_cnt, next_call, phi_cnt);
 903     block->map_node(n, phi_cnt++);    // Schedule him next
 904 
 905 #ifndef PRODUCT
 906     if (trace_opto_pipelining()) {
 907       tty->print("#    select %d: %s", n->_idx, n->Name());
 908       tty->print(", latency:%d", get_latency_for_node(n));
 909       n->dump();
 910       if (Verbose) {
 911         tty->print("#   ready list:");
 912         for( uint i=0; i<worklist.size(); i++ ) { // Inspect entire worklist
 913           Node *n = worklist[i];      // Get Node on worklist
 914           tty->print(" %d", n->_idx);
 915         }
 916         tty->cr();
 917       }
 918     }
 919 
 920 #endif
 921     if( n->is_MachCall() ) {
 922       MachCallNode *mcall = n->as_MachCall();
 923       phi_cnt = sched_call(block, phi_cnt, worklist, ready_cnt, mcall, next_call);
 924       continue;
 925     }
 926 
 927     if (n->is_Mach() && n->as_Mach()->has_call()) {
 928       RegMask regs;
 929       regs.Insert(_matcher.c_frame_pointer());
 930       regs.OR(n->out_RegMask());
 931 
 932       MachProjNode *proj = new (C) MachProjNode( n, 1, RegMask::Empty, MachProjNode::fat_proj );
 933       map_node_to_block(proj, block);
 934       block->insert_node(proj, phi_cnt++);
 935 
 936       add_call_kills(proj, regs, _matcher._c_reg_save_policy, false);
 937     }
 938 
 939     // Children are now all ready
 940     for (DUIterator_Fast i5max, i5 = n->fast_outs(i5max); i5 < i5max; i5++) {
 941       Node* m = n->fast_out(i5); // Get user
 942       if (get_block_for_node(m) != block) {
 943         continue;
 944       }
 945       if( m->is_Phi() ) continue;
 946       if (m->_idx >= max_idx) { // new node, skip it
 947         assert(m->is_MachProj() && n->is_Mach() && n->as_Mach()->has_call(), "unexpected node types");
 948         continue;
 949       }
 950       int m_cnt = ready_cnt.at(m->_idx)-1;
 951       ready_cnt.at_put(m->_idx, m_cnt);
 952       if( m_cnt == 0 )
 953         worklist.push(m);
 954     }
 955   }
 956 
 957   if( phi_cnt != block->end_idx() ) {
 958     // did not schedule all.  Retry, Bailout, or Die
 959     if (C->subsume_loads() == true && !C->failing()) {
 960       // Retry with subsume_loads == false
 961       // If this is the first failure, the sentinel string will "stick"
 962       // to the Compile object, and the C2Compiler will see it and retry.
 963       C->record_failure(C2Compiler::retry_no_subsuming_loads());
 964     } else {
 965       assert(false, "graph should be schedulable");
 966     }
 967     // assert( phi_cnt == end_idx(), "did not schedule all" );
 968     return false;
 969   }
 970 
 971 #ifndef PRODUCT
 972   if (trace_opto_pipelining()) {
 973     tty->print_cr("#");
 974     tty->print_cr("# after schedule_local");
 975     for (uint i = 0;i < block->number_of_nodes();i++) {
 976       tty->print("# ");
 977       block->get_node(i)->fast_dump();
 978     }
 979     tty->cr();
 980   }
 981 #endif
 982 
 983 
 984   return true;
 985 }
 986 
 987 //--------------------------catch_cleanup_fix_all_inputs-----------------------
 988 static void catch_cleanup_fix_all_inputs(Node *use, Node *old_def, Node *new_def) {
 989   for (uint l = 0; l < use->len(); l++) {
 990     if (use->in(l) == old_def) {
 991       if (l < use->req()) {
 992         use->set_req(l, new_def);
 993       } else {
 994         use->rm_prec(l);
 995         use->add_prec(new_def);
 996         l--;
 997       }
 998     }
 999   }
1000 }
1001 
1002 //------------------------------catch_cleanup_find_cloned_def------------------
1003 Node* PhaseCFG::catch_cleanup_find_cloned_def(Block *use_blk, Node *def, Block *def_blk, int n_clone_idx) {
1004   assert( use_blk != def_blk, "Inter-block cleanup only");
1005 
1006   // The use is some block below the Catch.  Find and return the clone of the def
1007   // that dominates the use. If there is no clone in a dominating block, then
1008   // create a phi for the def in a dominating block.
1009 
1010   // Find which successor block dominates this use.  The successor
1011   // blocks must all be single-entry (from the Catch only; I will have
1012   // split blocks to make this so), hence they all dominate.
1013   while( use_blk->_dom_depth > def_blk->_dom_depth+1 )
1014     use_blk = use_blk->_idom;
1015 
1016   // Find the successor
1017   Node *fixup = NULL;
1018 
1019   uint j;
1020   for( j = 0; j < def_blk->_num_succs; j++ )
1021     if( use_blk == def_blk->_succs[j] )
1022       break;
1023 
1024   if( j == def_blk->_num_succs ) {
1025     // Block at same level in dom-tree is not a successor.  It needs a
1026     // PhiNode, the PhiNode uses from the def and IT's uses need fixup.
1027     Node_Array inputs = new Node_List(Thread::current()->resource_area());
1028     for(uint k = 1; k < use_blk->num_preds(); k++) {
1029       Block* block = get_block_for_node(use_blk->pred(k));
1030       inputs.map(k, catch_cleanup_find_cloned_def(block, def, def_blk, n_clone_idx));
1031     }
1032 
1033     // Check to see if the use_blk already has an identical phi inserted.
1034     // If it exists, it will be at the first position since all uses of a
1035     // def are processed together.
1036     Node *phi = use_blk->get_node(1);
1037     if( phi->is_Phi() ) {
1038       fixup = phi;
1039       for (uint k = 1; k < use_blk->num_preds(); k++) {
1040         if (phi->in(k) != inputs[k]) {
1041           // Not a match
1042           fixup = NULL;
1043           break;
1044         }
1045       }
1046     }
1047 
1048     // If an existing PhiNode was not found, make a new one.
1049     if (fixup == NULL) {
1050       Node *new_phi = PhiNode::make(use_blk->head(), def);
1051       use_blk->insert_node(new_phi, 1);
1052       map_node_to_block(new_phi, use_blk);
1053       for (uint k = 1; k < use_blk->num_preds(); k++) {
1054         new_phi->set_req(k, inputs[k]);
1055       }
1056       fixup = new_phi;
1057     }
1058 
1059   } else {
1060     // Found the use just below the Catch.  Make it use the clone.
1061     fixup = use_blk->get_node(n_clone_idx);
1062   }
1063 
1064   return fixup;
1065 }
1066 
1067 //--------------------------catch_cleanup_intra_block--------------------------
1068 // Fix all input edges in use that reference "def".  The use is in the same
1069 // block as the def and both have been cloned in each successor block.
1070 static void catch_cleanup_intra_block(Node *use, Node *def, Block *blk, int beg, int n_clone_idx) {
1071 
1072   // Both the use and def have been cloned. For each successor block,
1073   // get the clone of the use, and make its input the clone of the def
1074   // found in that block.
1075 
1076   uint use_idx = blk->find_node(use);
1077   uint offset_idx = use_idx - beg;
1078   for( uint k = 0; k < blk->_num_succs; k++ ) {
1079     // Get clone in each successor block
1080     Block *sb = blk->_succs[k];
1081     Node *clone = sb->get_node(offset_idx+1);
1082     assert( clone->Opcode() == use->Opcode(), "" );
1083 
1084     // Make use-clone reference the def-clone
1085     catch_cleanup_fix_all_inputs(clone, def, sb->get_node(n_clone_idx));
1086   }
1087 }
1088 
1089 //------------------------------catch_cleanup_inter_block---------------------
1090 // Fix all input edges in use that reference "def".  The use is in a different
1091 // block than the def.
1092 void PhaseCFG::catch_cleanup_inter_block(Node *use, Block *use_blk, Node *def, Block *def_blk, int n_clone_idx) {
1093   if( !use_blk ) return;        // Can happen if the use is a precedence edge
1094 
1095   Node *new_def = catch_cleanup_find_cloned_def(use_blk, def, def_blk, n_clone_idx);
1096   catch_cleanup_fix_all_inputs(use, def, new_def);
1097 }
1098 
1099 //------------------------------call_catch_cleanup-----------------------------
1100 // If we inserted any instructions between a Call and his CatchNode,
1101 // clone the instructions on all paths below the Catch.
1102 void PhaseCFG::call_catch_cleanup(Block* block) {
1103 
1104   // End of region to clone
1105   uint end = block->end_idx();
1106   if( !block->get_node(end)->is_Catch() ) return;
1107   // Start of region to clone
1108   uint beg = end;
1109   while(!block->get_node(beg-1)->is_MachProj() ||
1110         !block->get_node(beg-1)->in(0)->is_MachCall() ) {
1111     beg--;
1112     assert(beg > 0,"Catch cleanup walking beyond block boundary");
1113   }
1114   // Range of inserted instructions is [beg, end)
1115   if( beg == end ) return;
1116 
1117   // Clone along all Catch output paths.  Clone area between the 'beg' and
1118   // 'end' indices.
1119   for( uint i = 0; i < block->_num_succs; i++ ) {
1120     Block *sb = block->_succs[i];
1121     // Clone the entire area; ignoring the edge fixup for now.
1122     for( uint j = end; j > beg; j-- ) {
1123       Node *clone = block->get_node(j-1)->clone();
1124       sb->insert_node(clone, 1);
1125       map_node_to_block(clone, sb);
1126       if (clone->needs_anti_dependence_check()) {
1127         insert_anti_dependences(sb, clone);
1128       }
1129     }
1130   }
1131 
1132 
1133   // Fixup edges.  Check the def-use info per cloned Node
1134   for(uint i2 = beg; i2 < end; i2++ ) {
1135     uint n_clone_idx = i2-beg+1; // Index of clone of n in each successor block
1136     Node *n = block->get_node(i2);        // Node that got cloned
1137     // Need DU safe iterator because of edge manipulation in calls.
1138     Unique_Node_List *out = new Unique_Node_List(Thread::current()->resource_area());
1139     for (DUIterator_Fast j1max, j1 = n->fast_outs(j1max); j1 < j1max; j1++) {
1140       out->push(n->fast_out(j1));
1141     }
1142     uint max = out->size();
1143     for (uint j = 0; j < max; j++) {// For all users
1144       Node *use = out->pop();
1145       Block *buse = get_block_for_node(use);
1146       if( use->is_Phi() ) {
1147         for( uint k = 1; k < use->req(); k++ )
1148           if( use->in(k) == n ) {
1149             Block* b = get_block_for_node(buse->pred(k));
1150             Node *fixup = catch_cleanup_find_cloned_def(b, n, block, n_clone_idx);
1151             use->set_req(k, fixup);
1152           }
1153       } else {
1154         if (block == buse) {
1155           catch_cleanup_intra_block(use, n, block, beg, n_clone_idx);
1156         } else {
1157           catch_cleanup_inter_block(use, buse, n, block, n_clone_idx);
1158         }
1159       }
1160     } // End for all users
1161 
1162   } // End of for all Nodes in cloned area
1163 
1164   // Remove the now-dead cloned ops
1165   for(uint i3 = beg; i3 < end; i3++ ) {
1166     block->get_node(beg)->disconnect_inputs(NULL, C);
1167     block->remove_node(beg);
1168   }
1169 
1170   // If the successor blocks have a CreateEx node, move it back to the top
1171   for(uint i4 = 0; i4 < block->_num_succs; i4++ ) {
1172     Block *sb = block->_succs[i4];
1173     uint new_cnt = end - beg;
1174     // Remove any newly created, but dead, nodes.
1175     for( uint j = new_cnt; j > 0; j-- ) {
1176       Node *n = sb->get_node(j);
1177       if (n->outcnt() == 0 &&
1178           (!n->is_Proj() || n->as_Proj()->in(0)->outcnt() == 1) ){
1179         n->disconnect_inputs(NULL, C);
1180         sb->remove_node(j);
1181         new_cnt--;
1182       }
1183     }
1184     // If any newly created nodes remain, move the CreateEx node to the top
1185     if (new_cnt > 0) {
1186       Node *cex = sb->get_node(1+new_cnt);
1187       if( cex->is_Mach() && cex->as_Mach()->ideal_Opcode() == Op_CreateEx ) {
1188         sb->remove_node(1+new_cnt);
1189         sb->insert_node(cex, 1);
1190       }
1191     }
1192   }
1193 }