src/share/vm/opto/lcm.cpp
Index Unified diffs Context diffs Sdiffs Patch New Old Previous File Next File JDK-8022284 Sdiff src/share/vm/opto

src/share/vm/opto/lcm.cpp

Print this page




 220       } else {
 221         const TypePtr* tptr;
 222         if (UseCompressedOops && (Universe::narrow_oop_shift() == 0 ||
 223                                   Universe::narrow_klass_shift() == 0)) {
 224           // 32-bits narrow oop can be the base of address expressions
 225           tptr = base->get_ptr_type();
 226         } else {
 227           // only regular oops are expected here
 228           tptr = base->bottom_type()->is_ptr();
 229         }
 230         // Give up if offset is not a compile-time constant
 231         if( offset == Type::OffsetBot || tptr->_offset == Type::OffsetBot )
 232           continue;
 233         offset += tptr->_offset; // correct if base is offseted
 234         if( MacroAssembler::needs_explicit_null_check(offset) )
 235           continue;             // Give up is reference is beyond 4K page size
 236       }
 237     }
 238 
 239     // Check ctrl input to see if the null-check dominates the memory op
 240     Block *cb = cfg->_bbs[mach->_idx];
 241     cb = cb->_idom;             // Always hoist at least 1 block
 242     if( !was_store ) {          // Stores can be hoisted only one block
 243       while( cb->_dom_depth > (_dom_depth + 1))
 244         cb = cb->_idom;         // Hoist loads as far as we want
 245       // The non-null-block should dominate the memory op, too. Live
 246       // range spilling will insert a spill in the non-null-block if it is
 247       // needs to spill the memory op for an implicit null check.
 248       if (cb->_dom_depth == (_dom_depth + 1)) {
 249         if (cb != not_null_block) continue;
 250         cb = cb->_idom;
 251       }
 252     }
 253     if( cb != this ) continue;
 254 
 255     // Found a memory user; see if it can be hoisted to check-block
 256     uint vidx = 0;              // Capture index of value into memop
 257     uint j;
 258     for( j = mach->req()-1; j > 0; j-- ) {
 259       if( mach->in(j) == val ) {
 260         vidx = j;
 261         // Ignore DecodeN val which could be hoisted to where needed.
 262         if( is_decoden ) continue;
 263       }
 264       // Block of memory-op input
 265       Block *inb = cfg->_bbs[mach->in(j)->_idx];
 266       Block *b = this;          // Start from nul check
 267       while( b != inb && b->_dom_depth > inb->_dom_depth )
 268         b = b->_idom;           // search upwards for input
 269       // See if input dominates null check
 270       if( b != inb )
 271         break;
 272     }
 273     if( j > 0 )
 274       continue;
 275     Block *mb = cfg->_bbs[mach->_idx];
 276     // Hoisting stores requires more checks for the anti-dependence case.
 277     // Give up hoisting if we have to move the store past any load.
 278     if( was_store ) {
 279       Block *b = mb;            // Start searching here for a local load
 280       // mach use (faulting) trying to hoist
 281       // n might be blocker to hoisting
 282       while( b != this ) {
 283         uint k;
 284         for( k = 1; k < b->_nodes.size(); k++ ) {
 285           Node *n = b->_nodes[k];
 286           if( n->needs_anti_dependence_check() &&
 287               n->in(LoadNode::Memory) == mach->in(StoreNode::Memory) )
 288             break;              // Found anti-dependent load
 289         }
 290         if( k < b->_nodes.size() )
 291           break;                // Found anti-dependent load
 292         // Make sure control does not do a merge (would have to check allpaths)
 293         if( b->num_preds() != 2 ) break;
 294         b = cfg->_bbs[b->pred(1)->_idx]; // Move up to predecessor block
 295       }
 296       if( b != this ) continue;
 297     }
 298 
 299     // Make sure this memory op is not already being used for a NullCheck
 300     Node *e = mb->end();
 301     if( e->is_MachNullCheck() && e->in(1) == mach )
 302       continue;                 // Already being used as a NULL check
 303 
 304     // Found a candidate!  Pick one with least dom depth - the highest
 305     // in the dom tree should be closest to the null check.
 306     if( !best ||
 307         cfg->_bbs[mach->_idx]->_dom_depth < cfg->_bbs[best->_idx]->_dom_depth ) {
 308       best = mach;
 309       bidx = vidx;
 310 
 311     }
 312   }
 313   // No candidate!
 314   if( !best ) return;


 315 
 316   // ---- Found an implicit null check
 317   extern int implicit_null_checks;
 318   implicit_null_checks++;
 319 
 320   if( is_decoden ) {
 321     // Check if we need to hoist decodeHeapOop_not_null first.
 322     Block *valb = cfg->_bbs[val->_idx];
 323     if( this != valb && this->_dom_depth < valb->_dom_depth ) {
 324       // Hoist it up to the end of the test block.
 325       valb->find_remove(val);
 326       this->add_inst(val);
 327       cfg->_bbs.map(val->_idx,this);
 328       // DecodeN on x86 may kill flags. Check for flag-killing projections
 329       // that also need to be hoisted.
 330       for (DUIterator_Fast jmax, j = val->fast_outs(jmax); j < jmax; j++) {
 331         Node* n = val->fast_out(j);
 332         if( n->is_MachProj() ) {
 333           cfg->_bbs[n->_idx]->find_remove(n);
 334           this->add_inst(n);
 335           cfg->_bbs.map(n->_idx,this);
 336         }
 337       }
 338     }
 339   }
 340   // Hoist the memory candidate up to the end of the test block.
 341   Block *old_block = cfg->_bbs[best->_idx];
 342   old_block->find_remove(best);
 343   add_inst(best);
 344   cfg->_bbs.map(best->_idx,this);
 345 
 346   // Move the control dependence
 347   if (best->in(0) && best->in(0) == old_block->_nodes[0])
 348     best->set_req(0, _nodes[0]);
 349 
 350   // Check for flag-killing projections that also need to be hoisted
 351   // Should be DU safe because no edge updates.
 352   for (DUIterator_Fast jmax, j = best->fast_outs(jmax); j < jmax; j++) {
 353     Node* n = best->fast_out(j);
 354     if( n->is_MachProj() ) {
 355       cfg->_bbs[n->_idx]->find_remove(n);
 356       add_inst(n);
 357       cfg->_bbs.map(n->_idx,this);
 358     }
 359   }
 360 
 361   Compile *C = cfg->C;
 362   // proj==Op_True --> ne test; proj==Op_False --> eq test.
 363   // One of two graph shapes got matched:
 364   //   (IfTrue  (If (Bool NE (CmpP ptr NULL))))
 365   //   (IfFalse (If (Bool EQ (CmpP ptr NULL))))
 366   // NULL checks are always branch-if-eq.  If we see a IfTrue projection
 367   // then we are replacing a 'ne' test with a 'eq' NULL check test.
 368   // We need to flip the projections to keep the same semantics.
 369   if( proj->Opcode() == Op_IfTrue ) {
 370     // Swap order of projections in basic block to swap branch targets
 371     Node *tmp1 = _nodes[end_idx()+1];
 372     Node *tmp2 = _nodes[end_idx()+2];
 373     _nodes.map(end_idx()+1, tmp2);
 374     _nodes.map(end_idx()+2, tmp1);
 375     Node *tmp = new (C) Node(C->top()); // Use not NULL input
 376     tmp1->replace_by(tmp);
 377     tmp2->replace_by(tmp1);
 378     tmp->replace_by(tmp2);
 379     tmp->destruct();
 380   }
 381 
 382   // Remove the existing null check; use a new implicit null check instead.
 383   // Since schedule-local needs precise def-use info, we need to correct
 384   // it as well.
 385   Node *old_tst = proj->in(0);
 386   MachNode *nul_chk = new (C) MachNullCheckNode(old_tst->in(0),best,bidx);
 387   _nodes.map(end_idx(),nul_chk);
 388   cfg->_bbs.map(nul_chk->_idx,this);
 389   // Redirect users of old_test to nul_chk
 390   for (DUIterator_Last i2min, i2 = old_tst->last_outs(i2min); i2 >= i2min; --i2)
 391     old_tst->last_out(i2)->set_req(0, nul_chk);
 392   // Clean-up any dead code
 393   for (uint i3 = 0; i3 < old_tst->req(); i3++)
 394     old_tst->set_req(i3, NULL);
 395 
 396   cfg->latency_from_uses(nul_chk);
 397   cfg->latency_from_uses(best);
 398 }
 399 
 400 
 401 //------------------------------select-----------------------------------------
 402 // Select a nice fellow from the worklist to schedule next. If there is only
 403 // one choice, then use it. Projections take top priority for correctness
 404 // reasons - if I see a projection, then it is next.  There are a number of
 405 // other special cases, for instructions that consume condition codes, et al.
 406 // These are chosen immediately. Some instructions are required to immediately
 407 // precede the last instruction in the block, and these are taken last. Of the
 408 // remaining cases (most), choose the instruction with the greatest latency


 451       continue;
 452 
 453     // Schedule IV increment last.
 454     if (e->is_Mach() && e->as_Mach()->ideal_Opcode() == Op_CountedLoopEnd &&
 455         e->in(1)->in(1) == n && n->is_iteratively_computed())
 456       continue;
 457 
 458     uint n_choice  = 2;
 459 
 460     // See if this instruction is consumed by a branch. If so, then (as the
 461     // branch is the last instruction in the basic block) force it to the
 462     // end of the basic block
 463     if ( must_clone[iop] ) {
 464       // See if any use is a branch
 465       bool found_machif = false;
 466 
 467       for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
 468         Node* use = n->fast_out(j);
 469 
 470         // The use is a conditional branch, make them adjacent
 471         if (use->is_MachIf() && cfg->_bbs[use->_idx]==this ) {
 472           found_machif = true;
 473           break;
 474         }
 475 
 476         // More than this instruction pending for successor to be ready,
 477         // don't choose this if other opportunities are ready
 478         if (ready_cnt.at(use->_idx) > 1)
 479           n_choice = 1;
 480       }
 481 
 482       // loop terminated, prefer not to use this instruction
 483       if (found_machif)
 484         continue;
 485     }
 486 
 487     // See if this has a predecessor that is "must_clone", i.e. sets the
 488     // condition code. If so, choose this first
 489     for (uint j = 0; j < n->req() ; j++) {
 490       Node *inn = n->in(j);
 491       if (inn) {


 512           (!StressLCM &&
 513            (latency < n_latency ||
 514             (latency == n_latency &&
 515              (score < n_score))))))) {
 516       choice  = n_choice;
 517       latency = n_latency;
 518       score   = n_score;
 519       idx     = i;               // Also keep index in worklist
 520     }
 521   } // End of for all ready nodes in worklist
 522 
 523   assert(idx >= 0, "index should be set");
 524   Node *n = worklist[(uint)idx];      // Get the winner
 525 
 526   worklist.map((uint)idx, worklist.pop());     // Compress worklist
 527   return n;
 528 }
 529 
 530 
 531 //------------------------------set_next_call----------------------------------
 532 void Block::set_next_call( Node *n, VectorSet &next_call, Block_Array &bbs ) {
 533   if( next_call.test_set(n->_idx) ) return;
 534   for( uint i=0; i<n->len(); i++ ) {
 535     Node *m = n->in(i);
 536     if( !m ) continue;  // must see all nodes in block that precede call
 537     if( bbs[m->_idx] == this )
 538       set_next_call( m, next_call, bbs );

 539   }
 540 }
 541 
 542 //------------------------------needed_for_next_call---------------------------
 543 // Set the flag 'next_call' for each Node that is needed for the next call to
 544 // be scheduled.  This flag lets me bias scheduling so Nodes needed for the
 545 // next subroutine call get priority - basically it moves things NOT needed
 546 // for the next call till after the call.  This prevents me from trying to
 547 // carry lots of stuff live across a call.
 548 void Block::needed_for_next_call(Node *this_call, VectorSet &next_call, Block_Array &bbs) {
 549   // Find the next control-defining Node in this block
 550   Node* call = NULL;
 551   for (DUIterator_Fast imax, i = this_call->fast_outs(imax); i < imax; i++) {
 552     Node* m = this_call->fast_out(i);
 553     if( bbs[m->_idx] == this && // Local-block user
 554         m != this_call &&       // Not self-start node
 555         m->is_MachCall() )
 556       call = m;
 557       break;
 558   }
 559   if (call == NULL)  return;    // No next call (e.g., block end is near)
 560   // Set next-call for all inputs to this call
 561   set_next_call(call, next_call, bbs);
 562 }
 563 
 564 //------------------------------add_call_kills-------------------------------------
 565 void Block::add_call_kills(MachProjNode *proj, RegMask& regs, const char* save_policy, bool exclude_soe) {
 566   // Fill in the kill mask for the call
 567   for( OptoReg::Name r = OptoReg::Name(0); r < _last_Mach_Reg; r=OptoReg::add(r,1) ) {
 568     if( !regs.Member(r) ) {     // Not already defined by the call
 569       // Save-on-call register?
 570       if ((save_policy[r] == 'C') ||
 571           (save_policy[r] == 'A') ||
 572           ((save_policy[r] == 'E') && exclude_soe)) {
 573         proj->_rout.Insert(r);
 574       }
 575     }
 576   }
 577 }
 578 
 579 
 580 //------------------------------sched_call-------------------------------------
 581 uint Block::sched_call( Matcher &matcher, Block_Array &bbs, uint node_cnt, Node_List &worklist, GrowableArray<int> &ready_cnt, MachCallNode *mcall, VectorSet &next_call ) {
 582   RegMask regs;
 583 
 584   // Schedule all the users of the call right now.  All the users are
 585   // projection Nodes, so they must be scheduled next to the call.
 586   // Collect all the defined registers.
 587   for (DUIterator_Fast imax, i = mcall->fast_outs(imax); i < imax; i++) {
 588     Node* n = mcall->fast_out(i);
 589     assert( n->is_MachProj(), "" );
 590     int n_cnt = ready_cnt.at(n->_idx)-1;
 591     ready_cnt.at_put(n->_idx, n_cnt);
 592     assert( n_cnt == 0, "" );
 593     // Schedule next to call
 594     _nodes.map(node_cnt++, n);
 595     // Collect defined registers
 596     regs.OR(n->out_RegMask());
 597     // Check for scheduling the next control-definer
 598     if( n->bottom_type() == Type::CONTROL )
 599       // Warm up next pile of heuristic bits
 600       needed_for_next_call(n, next_call, bbs);
 601 
 602     // Children of projections are now all ready
 603     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
 604       Node* m = n->fast_out(j); // Get user
 605       if( bbs[m->_idx] != this ) continue;


 606       if( m->is_Phi() ) continue;
 607       int m_cnt = ready_cnt.at(m->_idx)-1;
 608       ready_cnt.at_put(m->_idx, m_cnt);
 609       if( m_cnt == 0 )
 610         worklist.push(m);
 611     }
 612 
 613   }
 614 
 615   // Act as if the call defines the Frame Pointer.
 616   // Certainly the FP is alive and well after the call.
 617   regs.Insert(matcher.c_frame_pointer());
 618 
 619   // Set all registers killed and not already defined by the call.
 620   uint r_cnt = mcall->tf()->range()->cnt();
 621   int op = mcall->ideal_Opcode();
 622   MachProjNode *proj = new (matcher.C) MachProjNode( mcall, r_cnt+1, RegMask::Empty, MachProjNode::fat_proj );
 623   bbs.map(proj->_idx,this);
 624   _nodes.insert(node_cnt++, proj);
 625 
 626   // Select the right register save policy.
 627   const char * save_policy;
 628   switch (op) {
 629     case Op_CallRuntime:
 630     case Op_CallLeaf:
 631     case Op_CallLeafNoFP:
 632       // Calling C code so use C calling convention
 633       save_policy = matcher._c_reg_save_policy;
 634       break;
 635 
 636     case Op_CallStaticJava:
 637     case Op_CallDynamicJava:
 638       // Calling Java code so use Java calling convention
 639       save_policy = matcher._register_save_policy;
 640       break;
 641 
 642     default:
 643       ShouldNotReachHere();


 691   // RootNode is already sorted
 692   if( _nodes.size() == 1 ) return true;
 693 
 694   // Move PhiNodes and ParmNodes from 1 to cnt up to the start
 695   uint node_cnt = end_idx();
 696   uint phi_cnt = 1;
 697   uint i;
 698   for( i = 1; i<node_cnt; i++ ) { // Scan for Phi
 699     Node *n = _nodes[i];
 700     if( n->is_Phi() ||          // Found a PhiNode or ParmNode
 701         (n->is_Proj()  && n->in(0) == head()) ) {
 702       // Move guy at 'phi_cnt' to the end; makes a hole at phi_cnt
 703       _nodes.map(i,_nodes[phi_cnt]);
 704       _nodes.map(phi_cnt++,n);  // swap Phi/Parm up front
 705     } else {                    // All others
 706       // Count block-local inputs to 'n'
 707       uint cnt = n->len();      // Input count
 708       uint local = 0;
 709       for( uint j=0; j<cnt; j++ ) {
 710         Node *m = n->in(j);
 711         if( m && cfg->_bbs[m->_idx] == this && !m->is_top() )
 712           local++;              // One more block-local input
 713       }
 714       ready_cnt.at_put(n->_idx, local); // Count em up
 715 
 716 #ifdef ASSERT
 717       if( UseConcMarkSweepGC || UseG1GC ) {
 718         if( n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_StoreCM ) {
 719           // Check the precedence edges
 720           for (uint prec = n->req(); prec < n->len(); prec++) {
 721             Node* oop_store = n->in(prec);
 722             if (oop_store != NULL) {
 723               assert(cfg->_bbs[oop_store->_idx]->_dom_depth <= this->_dom_depth, "oop_store must dominate card-mark");
 724             }
 725           }
 726         }
 727       }
 728 #endif
 729 
 730       // A few node types require changing a required edge to a precedence edge
 731       // before allocation.
 732       if( n->is_Mach() && n->req() > TypeFunc::Parms &&
 733           (n->as_Mach()->ideal_Opcode() == Op_MemBarAcquire ||
 734            n->as_Mach()->ideal_Opcode() == Op_MemBarVolatile) ) {
 735         // MemBarAcquire could be created without Precedent edge.
 736         // del_req() replaces the specified edge with the last input edge
 737         // and then removes the last edge. If the specified edge > number of
 738         // edges the last edge will be moved outside of the input edges array
 739         // and the edge will be lost. This is why this code should be
 740         // executed only when Precedent (== TypeFunc::Parms) edge is present.
 741         Node *x = n->in(TypeFunc::Parms);
 742         n->del_req(TypeFunc::Parms);
 743         n->add_prec(x);
 744       }
 745     }
 746   }
 747   for(uint i2=i; i2<_nodes.size(); i2++ ) // Trailing guys get zapped count
 748     ready_cnt.at_put(_nodes[i2]->_idx, 0);
 749 
 750   // All the prescheduled guys do not hold back internal nodes
 751   uint i3;
 752   for(i3 = 0; i3<phi_cnt; i3++ ) {  // For all pre-scheduled
 753     Node *n = _nodes[i3];       // Get pre-scheduled
 754     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
 755       Node* m = n->fast_out(j);
 756       if( cfg->_bbs[m->_idx] ==this ) { // Local-block user
 757         int m_cnt = ready_cnt.at(m->_idx)-1;
 758         ready_cnt.at_put(m->_idx, m_cnt);   // Fix ready count
 759       }
 760     }
 761   }
 762 
 763   Node_List delay;
 764   // Make a worklist
 765   Node_List worklist;
 766   for(uint i4=i3; i4<node_cnt; i4++ ) {    // Put ready guys on worklist
 767     Node *m = _nodes[i4];
 768     if( !ready_cnt.at(m->_idx) ) {   // Zero ready count?
 769       if (m->is_iteratively_computed()) {
 770         // Push induction variable increments last to allow other uses
 771         // of the phi to be scheduled first. The select() method breaks
 772         // ties in scheduling by worklist order.
 773         delay.push(m);
 774       } else if (m->is_Mach() && m->as_Mach()->ideal_Opcode() == Op_CreateEx) {
 775         // Force the CreateEx to the top of the list so it's processed
 776         // first and ends up at the start of the block.
 777         worklist.insert(0, m);
 778       } else {
 779         worklist.push(m);         // Then on to worklist!
 780       }
 781     }
 782   }
 783   while (delay.size()) {
 784     Node* d = delay.pop();
 785     worklist.push(d);
 786   }
 787 
 788   // Warm up the 'next_call' heuristic bits
 789   needed_for_next_call(_nodes[0], next_call, cfg->_bbs);
 790 
 791 #ifndef PRODUCT
 792     if (cfg->trace_opto_pipelining()) {
 793       for (uint j=0; j<_nodes.size(); j++) {
 794         Node     *n = _nodes[j];
 795         int     idx = n->_idx;
 796         tty->print("#   ready cnt:%3d  ", ready_cnt.at(idx));
 797         tty->print("latency:%3d  ", cfg->_node_latency->at_grow(idx));
 798         tty->print("%4d: %s\n", idx, n->Name());
 799       }
 800     }
 801 #endif
 802 
 803   uint max_idx = (uint)ready_cnt.length();
 804   // Pull from worklist and schedule
 805   while( worklist.size() ) {    // Worklist is not ready
 806 
 807 #ifndef PRODUCT
 808     if (cfg->trace_opto_pipelining()) {
 809       tty->print("#   ready list:");


 820     _nodes.map(phi_cnt++,n);    // Schedule him next
 821 
 822 #ifndef PRODUCT
 823     if (cfg->trace_opto_pipelining()) {
 824       tty->print("#    select %d: %s", n->_idx, n->Name());
 825       tty->print(", latency:%d", cfg->_node_latency->at_grow(n->_idx));
 826       n->dump();
 827       if (Verbose) {
 828         tty->print("#   ready list:");
 829         for( uint i=0; i<worklist.size(); i++ ) { // Inspect entire worklist
 830           Node *n = worklist[i];      // Get Node on worklist
 831           tty->print(" %d", n->_idx);
 832         }
 833         tty->cr();
 834       }
 835     }
 836 
 837 #endif
 838     if( n->is_MachCall() ) {
 839       MachCallNode *mcall = n->as_MachCall();
 840       phi_cnt = sched_call(matcher, cfg->_bbs, phi_cnt, worklist, ready_cnt, mcall, next_call);
 841       continue;
 842     }
 843 
 844     if (n->is_Mach() && n->as_Mach()->has_call()) {
 845       RegMask regs;
 846       regs.Insert(matcher.c_frame_pointer());
 847       regs.OR(n->out_RegMask());
 848 
 849       MachProjNode *proj = new (matcher.C) MachProjNode( n, 1, RegMask::Empty, MachProjNode::fat_proj );
 850       cfg->_bbs.map(proj->_idx,this);
 851       _nodes.insert(phi_cnt++, proj);
 852 
 853       add_call_kills(proj, regs, matcher._c_reg_save_policy, false);
 854     }
 855 
 856     // Children are now all ready
 857     for (DUIterator_Fast i5max, i5 = n->fast_outs(i5max); i5 < i5max; i5++) {
 858       Node* m = n->fast_out(i5); // Get user
 859       if( cfg->_bbs[m->_idx] != this ) continue;


 860       if( m->is_Phi() ) continue;
 861       if (m->_idx >= max_idx) { // new node, skip it
 862         assert(m->is_MachProj() && n->is_Mach() && n->as_Mach()->has_call(), "unexpected node types");
 863         continue;
 864       }
 865       int m_cnt = ready_cnt.at(m->_idx)-1;
 866       ready_cnt.at_put(m->_idx, m_cnt);
 867       if( m_cnt == 0 )
 868         worklist.push(m);
 869     }
 870   }
 871 
 872   if( phi_cnt != end_idx() ) {
 873     // did not schedule all.  Retry, Bailout, or Die
 874     Compile* C = matcher.C;
 875     if (C->subsume_loads() == true && !C->failing()) {
 876       // Retry with subsume_loads == false
 877       // If this is the first failure, the sentinel string will "stick"
 878       // to the Compile object, and the C2Compiler will see it and retry.
 879       C->record_failure(C2Compiler::retry_no_subsuming_loads());


 897 
 898   return true;
 899 }
 900 
 901 //--------------------------catch_cleanup_fix_all_inputs-----------------------
 902 static void catch_cleanup_fix_all_inputs(Node *use, Node *old_def, Node *new_def) {
 903   for (uint l = 0; l < use->len(); l++) {
 904     if (use->in(l) == old_def) {
 905       if (l < use->req()) {
 906         use->set_req(l, new_def);
 907       } else {
 908         use->rm_prec(l);
 909         use->add_prec(new_def);
 910         l--;
 911       }
 912     }
 913   }
 914 }
 915 
 916 //------------------------------catch_cleanup_find_cloned_def------------------
 917 static Node *catch_cleanup_find_cloned_def(Block *use_blk, Node *def, Block *def_blk, Block_Array &bbs, int n_clone_idx) {
 918   assert( use_blk != def_blk, "Inter-block cleanup only");
 919 
 920   // The use is some block below the Catch.  Find and return the clone of the def
 921   // that dominates the use. If there is no clone in a dominating block, then
 922   // create a phi for the def in a dominating block.
 923 
 924   // Find which successor block dominates this use.  The successor
 925   // blocks must all be single-entry (from the Catch only; I will have
 926   // split blocks to make this so), hence they all dominate.
 927   while( use_blk->_dom_depth > def_blk->_dom_depth+1 )
 928     use_blk = use_blk->_idom;
 929 
 930   // Find the successor
 931   Node *fixup = NULL;
 932 
 933   uint j;
 934   for( j = 0; j < def_blk->_num_succs; j++ )
 935     if( use_blk == def_blk->_succs[j] )
 936       break;
 937 
 938   if( j == def_blk->_num_succs ) {
 939     // Block at same level in dom-tree is not a successor.  It needs a
 940     // PhiNode, the PhiNode uses from the def and IT's uses need fixup.
 941     Node_Array inputs = new Node_List(Thread::current()->resource_area());
 942     for(uint k = 1; k < use_blk->num_preds(); k++) {
 943       inputs.map(k, catch_cleanup_find_cloned_def(bbs[use_blk->pred(k)->_idx], def, def_blk, bbs, n_clone_idx));

 944     }
 945 
 946     // Check to see if the use_blk already has an identical phi inserted.
 947     // If it exists, it will be at the first position since all uses of a
 948     // def are processed together.
 949     Node *phi = use_blk->_nodes[1];
 950     if( phi->is_Phi() ) {
 951       fixup = phi;
 952       for (uint k = 1; k < use_blk->num_preds(); k++) {
 953         if (phi->in(k) != inputs[k]) {
 954           // Not a match
 955           fixup = NULL;
 956           break;
 957         }
 958       }
 959     }
 960 
 961     // If an existing PhiNode was not found, make a new one.
 962     if (fixup == NULL) {
 963       Node *new_phi = PhiNode::make(use_blk->head(), def);
 964       use_blk->_nodes.insert(1, new_phi);
 965       bbs.map(new_phi->_idx, use_blk);
 966       for (uint k = 1; k < use_blk->num_preds(); k++) {
 967         new_phi->set_req(k, inputs[k]);
 968       }
 969       fixup = new_phi;
 970     }
 971 
 972   } else {
 973     // Found the use just below the Catch.  Make it use the clone.
 974     fixup = use_blk->_nodes[n_clone_idx];
 975   }
 976 
 977   return fixup;
 978 }
 979 
 980 //--------------------------catch_cleanup_intra_block--------------------------
 981 // Fix all input edges in use that reference "def".  The use is in the same
 982 // block as the def and both have been cloned in each successor block.
 983 static void catch_cleanup_intra_block(Node *use, Node *def, Block *blk, int beg, int n_clone_idx) {
 984 
 985   // Both the use and def have been cloned. For each successor block,
 986   // get the clone of the use, and make its input the clone of the def
 987   // found in that block.
 988 
 989   uint use_idx = blk->find_node(use);
 990   uint offset_idx = use_idx - beg;
 991   for( uint k = 0; k < blk->_num_succs; k++ ) {
 992     // Get clone in each successor block
 993     Block *sb = blk->_succs[k];
 994     Node *clone = sb->_nodes[offset_idx+1];
 995     assert( clone->Opcode() == use->Opcode(), "" );
 996 
 997     // Make use-clone reference the def-clone
 998     catch_cleanup_fix_all_inputs(clone, def, sb->_nodes[n_clone_idx]);
 999   }
1000 }
1001 
1002 //------------------------------catch_cleanup_inter_block---------------------
1003 // Fix all input edges in use that reference "def".  The use is in a different
1004 // block than the def.
1005 static void catch_cleanup_inter_block(Node *use, Block *use_blk, Node *def, Block *def_blk, Block_Array &bbs, int n_clone_idx) {
1006   if( !use_blk ) return;        // Can happen if the use is a precedence edge
1007 
1008   Node *new_def = catch_cleanup_find_cloned_def(use_blk, def, def_blk, bbs, n_clone_idx);
1009   catch_cleanup_fix_all_inputs(use, def, new_def);
1010 }
1011 
1012 //------------------------------call_catch_cleanup-----------------------------
1013 // If we inserted any instructions between a Call and his CatchNode,
1014 // clone the instructions on all paths below the Catch.
1015 void Block::call_catch_cleanup(Block_Array &bbs, Compile* C) {
1016 
1017   // End of region to clone
1018   uint end = end_idx();
1019   if( !_nodes[end]->is_Catch() ) return;
1020   // Start of region to clone
1021   uint beg = end;
1022   while(!_nodes[beg-1]->is_MachProj() ||
1023         !_nodes[beg-1]->in(0)->is_MachCall() ) {
1024     beg--;
1025     assert(beg > 0,"Catch cleanup walking beyond block boundary");
1026   }
1027   // Range of inserted instructions is [beg, end)
1028   if( beg == end ) return;
1029 
1030   // Clone along all Catch output paths.  Clone area between the 'beg' and
1031   // 'end' indices.
1032   for( uint i = 0; i < _num_succs; i++ ) {
1033     Block *sb = _succs[i];
1034     // Clone the entire area; ignoring the edge fixup for now.
1035     for( uint j = end; j > beg; j-- ) {
1036       // It is safe here to clone a node with anti_dependence
1037       // since clones dominate on each path.
1038       Node *clone = _nodes[j-1]->clone();
1039       sb->_nodes.insert( 1, clone );
1040       bbs.map(clone->_idx,sb);
1041     }
1042   }
1043 
1044 
1045   // Fixup edges.  Check the def-use info per cloned Node
1046   for(uint i2 = beg; i2 < end; i2++ ) {
1047     uint n_clone_idx = i2-beg+1; // Index of clone of n in each successor block
1048     Node *n = _nodes[i2];        // Node that got cloned
1049     // Need DU safe iterator because of edge manipulation in calls.
1050     Unique_Node_List *out = new Unique_Node_List(Thread::current()->resource_area());
1051     for (DUIterator_Fast j1max, j1 = n->fast_outs(j1max); j1 < j1max; j1++) {
1052       out->push(n->fast_out(j1));
1053     }
1054     uint max = out->size();
1055     for (uint j = 0; j < max; j++) {// For all users
1056       Node *use = out->pop();
1057       Block *buse = bbs[use->_idx];
1058       if( use->is_Phi() ) {
1059         for( uint k = 1; k < use->req(); k++ )
1060           if( use->in(k) == n ) {
1061             Node *fixup = catch_cleanup_find_cloned_def(bbs[buse->pred(k)->_idx], n, this, bbs, n_clone_idx);

1062             use->set_req(k, fixup);
1063           }
1064       } else {
1065         if (this == buse) {
1066           catch_cleanup_intra_block(use, n, this, beg, n_clone_idx);
1067         } else {
1068           catch_cleanup_inter_block(use, buse, n, this, bbs, n_clone_idx);
1069         }
1070       }
1071     } // End for all users
1072 
1073   } // End of for all Nodes in cloned area
1074 
1075   // Remove the now-dead cloned ops
1076   for(uint i3 = beg; i3 < end; i3++ ) {
1077     _nodes[beg]->disconnect_inputs(NULL, C);
1078     _nodes.remove(beg);
1079   }
1080 
1081   // If the successor blocks have a CreateEx node, move it back to the top
1082   for(uint i4 = 0; i4 < _num_succs; i4++ ) {
1083     Block *sb = _succs[i4];
1084     uint new_cnt = end - beg;
1085     // Remove any newly created, but dead, nodes.
1086     for( uint j = new_cnt; j > 0; j-- ) {
1087       Node *n = sb->_nodes[j];
1088       if (n->outcnt() == 0 &&


 220       } else {
 221         const TypePtr* tptr;
 222         if (UseCompressedOops && (Universe::narrow_oop_shift() == 0 ||
 223                                   Universe::narrow_klass_shift() == 0)) {
 224           // 32-bits narrow oop can be the base of address expressions
 225           tptr = base->get_ptr_type();
 226         } else {
 227           // only regular oops are expected here
 228           tptr = base->bottom_type()->is_ptr();
 229         }
 230         // Give up if offset is not a compile-time constant
 231         if( offset == Type::OffsetBot || tptr->_offset == Type::OffsetBot )
 232           continue;
 233         offset += tptr->_offset; // correct if base is offseted
 234         if( MacroAssembler::needs_explicit_null_check(offset) )
 235           continue;             // Give up is reference is beyond 4K page size
 236       }
 237     }
 238 
 239     // Check ctrl input to see if the null-check dominates the memory op
 240     Block *cb = cfg->get_block_for_node(mach);
 241     cb = cb->_idom;             // Always hoist at least 1 block
 242     if( !was_store ) {          // Stores can be hoisted only one block
 243       while( cb->_dom_depth > (_dom_depth + 1))
 244         cb = cb->_idom;         // Hoist loads as far as we want
 245       // The non-null-block should dominate the memory op, too. Live
 246       // range spilling will insert a spill in the non-null-block if it is
 247       // needs to spill the memory op for an implicit null check.
 248       if (cb->_dom_depth == (_dom_depth + 1)) {
 249         if (cb != not_null_block) continue;
 250         cb = cb->_idom;
 251       }
 252     }
 253     if( cb != this ) continue;
 254 
 255     // Found a memory user; see if it can be hoisted to check-block
 256     uint vidx = 0;              // Capture index of value into memop
 257     uint j;
 258     for( j = mach->req()-1; j > 0; j-- ) {
 259       if( mach->in(j) == val ) {
 260         vidx = j;
 261         // Ignore DecodeN val which could be hoisted to where needed.
 262         if( is_decoden ) continue;
 263       }
 264       // Block of memory-op input
 265       Block *inb = cfg->get_block_for_node(mach->in(j));
 266       Block *b = this;          // Start from nul check
 267       while( b != inb && b->_dom_depth > inb->_dom_depth )
 268         b = b->_idom;           // search upwards for input
 269       // See if input dominates null check
 270       if( b != inb )
 271         break;
 272     }
 273     if( j > 0 )
 274       continue;
 275     Block *mb = cfg->get_block_for_node(mach);
 276     // Hoisting stores requires more checks for the anti-dependence case.
 277     // Give up hoisting if we have to move the store past any load.
 278     if( was_store ) {
 279       Block *b = mb;            // Start searching here for a local load
 280       // mach use (faulting) trying to hoist
 281       // n might be blocker to hoisting
 282       while( b != this ) {
 283         uint k;
 284         for( k = 1; k < b->_nodes.size(); k++ ) {
 285           Node *n = b->_nodes[k];
 286           if( n->needs_anti_dependence_check() &&
 287               n->in(LoadNode::Memory) == mach->in(StoreNode::Memory) )
 288             break;              // Found anti-dependent load
 289         }
 290         if( k < b->_nodes.size() )
 291           break;                // Found anti-dependent load
 292         // Make sure control does not do a merge (would have to check allpaths)
 293         if( b->num_preds() != 2 ) break;
 294         b = cfg->get_block_for_node(b->pred(1)); // Move up to predecessor block
 295       }
 296       if( b != this ) continue;
 297     }
 298 
 299     // Make sure this memory op is not already being used for a NullCheck
 300     Node *e = mb->end();
 301     if( e->is_MachNullCheck() && e->in(1) == mach )
 302       continue;                 // Already being used as a NULL check
 303 
 304     // Found a candidate!  Pick one with least dom depth - the highest
 305     // in the dom tree should be closest to the null check.
 306     if (!best || cfg->get_block_for_node(mach)->_dom_depth < cfg->get_block_for_node(best)->_dom_depth) {

 307       best = mach;
 308       bidx = vidx;

 309     }
 310   }
 311   // No candidate!
 312   if (!best) {
 313     return;
 314   }
 315 
 316   // ---- Found an implicit null check
 317   extern int implicit_null_checks;
 318   implicit_null_checks++;
 319 
 320   if( is_decoden ) {
 321     // Check if we need to hoist decodeHeapOop_not_null first.
 322     Block *valb = cfg->get_block_for_node(val);
 323     if( this != valb && this->_dom_depth < valb->_dom_depth ) {
 324       // Hoist it up to the end of the test block.
 325       valb->find_remove(val);
 326       this->add_inst(val);
 327       cfg->map_node_to_block(val, this);
 328       // DecodeN on x86 may kill flags. Check for flag-killing projections
 329       // that also need to be hoisted.
 330       for (DUIterator_Fast jmax, j = val->fast_outs(jmax); j < jmax; j++) {
 331         Node* n = val->fast_out(j);
 332         if( n->is_MachProj() ) {
 333           cfg->get_block_for_node(n)->find_remove(n);
 334           this->add_inst(n);
 335           cfg->map_node_to_block(n, this);
 336         }
 337       }
 338     }
 339   }
 340   // Hoist the memory candidate up to the end of the test block.
 341   Block *old_block = cfg->get_block_for_node(best);
 342   old_block->find_remove(best);
 343   add_inst(best);
 344   cfg->map_node_to_block(best, this);
 345 
 346   // Move the control dependence
 347   if (best->in(0) && best->in(0) == old_block->_nodes[0])
 348     best->set_req(0, _nodes[0]);
 349 
 350   // Check for flag-killing projections that also need to be hoisted
 351   // Should be DU safe because no edge updates.
 352   for (DUIterator_Fast jmax, j = best->fast_outs(jmax); j < jmax; j++) {
 353     Node* n = best->fast_out(j);
 354     if( n->is_MachProj() ) {
 355       cfg->get_block_for_node(n)->find_remove(n);
 356       add_inst(n);
 357       cfg->map_node_to_block(n, this);
 358     }
 359   }
 360 
 361   Compile *C = cfg->C;
 362   // proj==Op_True --> ne test; proj==Op_False --> eq test.
 363   // One of two graph shapes got matched:
 364   //   (IfTrue  (If (Bool NE (CmpP ptr NULL))))
 365   //   (IfFalse (If (Bool EQ (CmpP ptr NULL))))
 366   // NULL checks are always branch-if-eq.  If we see a IfTrue projection
 367   // then we are replacing a 'ne' test with a 'eq' NULL check test.
 368   // We need to flip the projections to keep the same semantics.
 369   if( proj->Opcode() == Op_IfTrue ) {
 370     // Swap order of projections in basic block to swap branch targets
 371     Node *tmp1 = _nodes[end_idx()+1];
 372     Node *tmp2 = _nodes[end_idx()+2];
 373     _nodes.map(end_idx()+1, tmp2);
 374     _nodes.map(end_idx()+2, tmp1);
 375     Node *tmp = new (C) Node(C->top()); // Use not NULL input
 376     tmp1->replace_by(tmp);
 377     tmp2->replace_by(tmp1);
 378     tmp->replace_by(tmp2);
 379     tmp->destruct();
 380   }
 381 
 382   // Remove the existing null check; use a new implicit null check instead.
 383   // Since schedule-local needs precise def-use info, we need to correct
 384   // it as well.
 385   Node *old_tst = proj->in(0);
 386   MachNode *nul_chk = new (C) MachNullCheckNode(old_tst->in(0),best,bidx);
 387   _nodes.map(end_idx(),nul_chk);
 388   cfg->map_node_to_block(nul_chk, this);
 389   // Redirect users of old_test to nul_chk
 390   for (DUIterator_Last i2min, i2 = old_tst->last_outs(i2min); i2 >= i2min; --i2)
 391     old_tst->last_out(i2)->set_req(0, nul_chk);
 392   // Clean-up any dead code
 393   for (uint i3 = 0; i3 < old_tst->req(); i3++)
 394     old_tst->set_req(i3, NULL);
 395 
 396   cfg->latency_from_uses(nul_chk);
 397   cfg->latency_from_uses(best);
 398 }
 399 
 400 
 401 //------------------------------select-----------------------------------------
 402 // Select a nice fellow from the worklist to schedule next. If there is only
 403 // one choice, then use it. Projections take top priority for correctness
 404 // reasons - if I see a projection, then it is next.  There are a number of
 405 // other special cases, for instructions that consume condition codes, et al.
 406 // These are chosen immediately. Some instructions are required to immediately
 407 // precede the last instruction in the block, and these are taken last. Of the
 408 // remaining cases (most), choose the instruction with the greatest latency


 451       continue;
 452 
 453     // Schedule IV increment last.
 454     if (e->is_Mach() && e->as_Mach()->ideal_Opcode() == Op_CountedLoopEnd &&
 455         e->in(1)->in(1) == n && n->is_iteratively_computed())
 456       continue;
 457 
 458     uint n_choice  = 2;
 459 
 460     // See if this instruction is consumed by a branch. If so, then (as the
 461     // branch is the last instruction in the basic block) force it to the
 462     // end of the basic block
 463     if ( must_clone[iop] ) {
 464       // See if any use is a branch
 465       bool found_machif = false;
 466 
 467       for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
 468         Node* use = n->fast_out(j);
 469 
 470         // The use is a conditional branch, make them adjacent
 471         if (use->is_MachIf() && cfg->get_block_for_node(use) == this) {
 472           found_machif = true;
 473           break;
 474         }
 475 
 476         // More than this instruction pending for successor to be ready,
 477         // don't choose this if other opportunities are ready
 478         if (ready_cnt.at(use->_idx) > 1)
 479           n_choice = 1;
 480       }
 481 
 482       // loop terminated, prefer not to use this instruction
 483       if (found_machif)
 484         continue;
 485     }
 486 
 487     // See if this has a predecessor that is "must_clone", i.e. sets the
 488     // condition code. If so, choose this first
 489     for (uint j = 0; j < n->req() ; j++) {
 490       Node *inn = n->in(j);
 491       if (inn) {


 512           (!StressLCM &&
 513            (latency < n_latency ||
 514             (latency == n_latency &&
 515              (score < n_score))))))) {
 516       choice  = n_choice;
 517       latency = n_latency;
 518       score   = n_score;
 519       idx     = i;               // Also keep index in worklist
 520     }
 521   } // End of for all ready nodes in worklist
 522 
 523   assert(idx >= 0, "index should be set");
 524   Node *n = worklist[(uint)idx];      // Get the winner
 525 
 526   worklist.map((uint)idx, worklist.pop());     // Compress worklist
 527   return n;
 528 }
 529 
 530 
 531 //------------------------------set_next_call----------------------------------
 532 void Block::set_next_call( Node *n, VectorSet &next_call, PhaseCFG* cfg) {
 533   if( next_call.test_set(n->_idx) ) return;
 534   for( uint i=0; i<n->len(); i++ ) {
 535     Node *m = n->in(i);
 536     if( !m ) continue;  // must see all nodes in block that precede call
 537     if (cfg->get_block_for_node(m) == this) {
 538       set_next_call(m, next_call, cfg);
 539     }
 540   }
 541 }
 542 
 543 //------------------------------needed_for_next_call---------------------------
 544 // Set the flag 'next_call' for each Node that is needed for the next call to
 545 // be scheduled.  This flag lets me bias scheduling so Nodes needed for the
 546 // next subroutine call get priority - basically it moves things NOT needed
 547 // for the next call till after the call.  This prevents me from trying to
 548 // carry lots of stuff live across a call.
 549 void Block::needed_for_next_call(Node *this_call, VectorSet &next_call, PhaseCFG* cfg) {
 550   // Find the next control-defining Node in this block
 551   Node* call = NULL;
 552   for (DUIterator_Fast imax, i = this_call->fast_outs(imax); i < imax; i++) {
 553     Node* m = this_call->fast_out(i);
 554     if(cfg->get_block_for_node(m) == this && // Local-block user
 555         m != this_call &&       // Not self-start node
 556         m->is_MachCall() )
 557       call = m;
 558       break;
 559   }
 560   if (call == NULL)  return;    // No next call (e.g., block end is near)
 561   // Set next-call for all inputs to this call
 562   set_next_call(call, next_call, cfg);
 563 }
 564 
 565 //------------------------------add_call_kills-------------------------------------
 566 void Block::add_call_kills(MachProjNode *proj, RegMask& regs, const char* save_policy, bool exclude_soe) {
 567   // Fill in the kill mask for the call
 568   for( OptoReg::Name r = OptoReg::Name(0); r < _last_Mach_Reg; r=OptoReg::add(r,1) ) {
 569     if( !regs.Member(r) ) {     // Not already defined by the call
 570       // Save-on-call register?
 571       if ((save_policy[r] == 'C') ||
 572           (save_policy[r] == 'A') ||
 573           ((save_policy[r] == 'E') && exclude_soe)) {
 574         proj->_rout.Insert(r);
 575       }
 576     }
 577   }
 578 }
 579 
 580 
 581 //------------------------------sched_call-------------------------------------
 582 uint Block::sched_call( Matcher &matcher, PhaseCFG* cfg, uint node_cnt, Node_List &worklist, GrowableArray<int> &ready_cnt, MachCallNode *mcall, VectorSet &next_call ) {
 583   RegMask regs;
 584 
 585   // Schedule all the users of the call right now.  All the users are
 586   // projection Nodes, so they must be scheduled next to the call.
 587   // Collect all the defined registers.
 588   for (DUIterator_Fast imax, i = mcall->fast_outs(imax); i < imax; i++) {
 589     Node* n = mcall->fast_out(i);
 590     assert( n->is_MachProj(), "" );
 591     int n_cnt = ready_cnt.at(n->_idx)-1;
 592     ready_cnt.at_put(n->_idx, n_cnt);
 593     assert( n_cnt == 0, "" );
 594     // Schedule next to call
 595     _nodes.map(node_cnt++, n);
 596     // Collect defined registers
 597     regs.OR(n->out_RegMask());
 598     // Check for scheduling the next control-definer
 599     if( n->bottom_type() == Type::CONTROL )
 600       // Warm up next pile of heuristic bits
 601       needed_for_next_call(n, next_call, cfg);
 602 
 603     // Children of projections are now all ready
 604     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
 605       Node* m = n->fast_out(j); // Get user
 606       if(cfg->get_block_for_node(m) != this) {
 607         continue;
 608       }
 609       if( m->is_Phi() ) continue;
 610       int m_cnt = ready_cnt.at(m->_idx)-1;
 611       ready_cnt.at_put(m->_idx, m_cnt);
 612       if( m_cnt == 0 )
 613         worklist.push(m);
 614     }
 615 
 616   }
 617 
 618   // Act as if the call defines the Frame Pointer.
 619   // Certainly the FP is alive and well after the call.
 620   regs.Insert(matcher.c_frame_pointer());
 621 
 622   // Set all registers killed and not already defined by the call.
 623   uint r_cnt = mcall->tf()->range()->cnt();
 624   int op = mcall->ideal_Opcode();
 625   MachProjNode *proj = new (matcher.C) MachProjNode( mcall, r_cnt+1, RegMask::Empty, MachProjNode::fat_proj );
 626   cfg->map_node_to_block(proj, this);
 627   _nodes.insert(node_cnt++, proj);
 628 
 629   // Select the right register save policy.
 630   const char * save_policy;
 631   switch (op) {
 632     case Op_CallRuntime:
 633     case Op_CallLeaf:
 634     case Op_CallLeafNoFP:
 635       // Calling C code so use C calling convention
 636       save_policy = matcher._c_reg_save_policy;
 637       break;
 638 
 639     case Op_CallStaticJava:
 640     case Op_CallDynamicJava:
 641       // Calling Java code so use Java calling convention
 642       save_policy = matcher._register_save_policy;
 643       break;
 644 
 645     default:
 646       ShouldNotReachHere();


 694   // RootNode is already sorted
 695   if( _nodes.size() == 1 ) return true;
 696 
 697   // Move PhiNodes and ParmNodes from 1 to cnt up to the start
 698   uint node_cnt = end_idx();
 699   uint phi_cnt = 1;
 700   uint i;
 701   for( i = 1; i<node_cnt; i++ ) { // Scan for Phi
 702     Node *n = _nodes[i];
 703     if( n->is_Phi() ||          // Found a PhiNode or ParmNode
 704         (n->is_Proj()  && n->in(0) == head()) ) {
 705       // Move guy at 'phi_cnt' to the end; makes a hole at phi_cnt
 706       _nodes.map(i,_nodes[phi_cnt]);
 707       _nodes.map(phi_cnt++,n);  // swap Phi/Parm up front
 708     } else {                    // All others
 709       // Count block-local inputs to 'n'
 710       uint cnt = n->len();      // Input count
 711       uint local = 0;
 712       for( uint j=0; j<cnt; j++ ) {
 713         Node *m = n->in(j);
 714         if( m && cfg->get_block_for_node(m) == this && !m->is_top() )
 715           local++;              // One more block-local input
 716       }
 717       ready_cnt.at_put(n->_idx, local); // Count em up
 718 
 719 #ifdef ASSERT
 720       if( UseConcMarkSweepGC || UseG1GC ) {
 721         if( n->is_Mach() && n->as_Mach()->ideal_Opcode() == Op_StoreCM ) {
 722           // Check the precedence edges
 723           for (uint prec = n->req(); prec < n->len(); prec++) {
 724             Node* oop_store = n->in(prec);
 725             if (oop_store != NULL) {
 726               assert(cfg->get_block_for_node(oop_store)->_dom_depth <= this->_dom_depth, "oop_store must dominate card-mark");
 727             }
 728           }
 729         }
 730       }
 731 #endif
 732 
 733       // A few node types require changing a required edge to a precedence edge
 734       // before allocation.
 735       if( n->is_Mach() && n->req() > TypeFunc::Parms &&
 736           (n->as_Mach()->ideal_Opcode() == Op_MemBarAcquire ||
 737            n->as_Mach()->ideal_Opcode() == Op_MemBarVolatile) ) {
 738         // MemBarAcquire could be created without Precedent edge.
 739         // del_req() replaces the specified edge with the last input edge
 740         // and then removes the last edge. If the specified edge > number of
 741         // edges the last edge will be moved outside of the input edges array
 742         // and the edge will be lost. This is why this code should be
 743         // executed only when Precedent (== TypeFunc::Parms) edge is present.
 744         Node *x = n->in(TypeFunc::Parms);
 745         n->del_req(TypeFunc::Parms);
 746         n->add_prec(x);
 747       }
 748     }
 749   }
 750   for(uint i2=i; i2<_nodes.size(); i2++ ) // Trailing guys get zapped count
 751     ready_cnt.at_put(_nodes[i2]->_idx, 0);
 752 
 753   // All the prescheduled guys do not hold back internal nodes
 754   uint i3;
 755   for(i3 = 0; i3<phi_cnt; i3++ ) {  // For all pre-scheduled
 756     Node *n = _nodes[i3];       // Get pre-scheduled
 757     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
 758       Node* m = n->fast_out(j);
 759       if (cfg->get_block_for_node(m) == this) { // Local-block user
 760         int m_cnt = ready_cnt.at(m->_idx)-1;
 761         ready_cnt.at_put(m->_idx, m_cnt);   // Fix ready count
 762       }
 763     }
 764   }
 765 
 766   Node_List delay;
 767   // Make a worklist
 768   Node_List worklist;
 769   for(uint i4=i3; i4<node_cnt; i4++ ) {    // Put ready guys on worklist
 770     Node *m = _nodes[i4];
 771     if( !ready_cnt.at(m->_idx) ) {   // Zero ready count?
 772       if (m->is_iteratively_computed()) {
 773         // Push induction variable increments last to allow other uses
 774         // of the phi to be scheduled first. The select() method breaks
 775         // ties in scheduling by worklist order.
 776         delay.push(m);
 777       } else if (m->is_Mach() && m->as_Mach()->ideal_Opcode() == Op_CreateEx) {
 778         // Force the CreateEx to the top of the list so it's processed
 779         // first and ends up at the start of the block.
 780         worklist.insert(0, m);
 781       } else {
 782         worklist.push(m);         // Then on to worklist!
 783       }
 784     }
 785   }
 786   while (delay.size()) {
 787     Node* d = delay.pop();
 788     worklist.push(d);
 789   }
 790 
 791   // Warm up the 'next_call' heuristic bits
 792   needed_for_next_call(_nodes[0], next_call, cfg);
 793 
 794 #ifndef PRODUCT
 795     if (cfg->trace_opto_pipelining()) {
 796       for (uint j=0; j<_nodes.size(); j++) {
 797         Node     *n = _nodes[j];
 798         int     idx = n->_idx;
 799         tty->print("#   ready cnt:%3d  ", ready_cnt.at(idx));
 800         tty->print("latency:%3d  ", cfg->_node_latency->at_grow(idx));
 801         tty->print("%4d: %s\n", idx, n->Name());
 802       }
 803     }
 804 #endif
 805 
 806   uint max_idx = (uint)ready_cnt.length();
 807   // Pull from worklist and schedule
 808   while( worklist.size() ) {    // Worklist is not ready
 809 
 810 #ifndef PRODUCT
 811     if (cfg->trace_opto_pipelining()) {
 812       tty->print("#   ready list:");


 823     _nodes.map(phi_cnt++,n);    // Schedule him next
 824 
 825 #ifndef PRODUCT
 826     if (cfg->trace_opto_pipelining()) {
 827       tty->print("#    select %d: %s", n->_idx, n->Name());
 828       tty->print(", latency:%d", cfg->_node_latency->at_grow(n->_idx));
 829       n->dump();
 830       if (Verbose) {
 831         tty->print("#   ready list:");
 832         for( uint i=0; i<worklist.size(); i++ ) { // Inspect entire worklist
 833           Node *n = worklist[i];      // Get Node on worklist
 834           tty->print(" %d", n->_idx);
 835         }
 836         tty->cr();
 837       }
 838     }
 839 
 840 #endif
 841     if( n->is_MachCall() ) {
 842       MachCallNode *mcall = n->as_MachCall();
 843       phi_cnt = sched_call(matcher, cfg, phi_cnt, worklist, ready_cnt, mcall, next_call);
 844       continue;
 845     }
 846 
 847     if (n->is_Mach() && n->as_Mach()->has_call()) {
 848       RegMask regs;
 849       regs.Insert(matcher.c_frame_pointer());
 850       regs.OR(n->out_RegMask());
 851 
 852       MachProjNode *proj = new (matcher.C) MachProjNode( n, 1, RegMask::Empty, MachProjNode::fat_proj );
 853       cfg->map_node_to_block(proj, this);
 854       _nodes.insert(phi_cnt++, proj);
 855 
 856       add_call_kills(proj, regs, matcher._c_reg_save_policy, false);
 857     }
 858 
 859     // Children are now all ready
 860     for (DUIterator_Fast i5max, i5 = n->fast_outs(i5max); i5 < i5max; i5++) {
 861       Node* m = n->fast_out(i5); // Get user
 862       if (cfg->get_block_for_node(m) != this) {
 863         continue;
 864       }
 865       if( m->is_Phi() ) continue;
 866       if (m->_idx >= max_idx) { // new node, skip it
 867         assert(m->is_MachProj() && n->is_Mach() && n->as_Mach()->has_call(), "unexpected node types");
 868         continue;
 869       }
 870       int m_cnt = ready_cnt.at(m->_idx)-1;
 871       ready_cnt.at_put(m->_idx, m_cnt);
 872       if( m_cnt == 0 )
 873         worklist.push(m);
 874     }
 875   }
 876 
 877   if( phi_cnt != end_idx() ) {
 878     // did not schedule all.  Retry, Bailout, or Die
 879     Compile* C = matcher.C;
 880     if (C->subsume_loads() == true && !C->failing()) {
 881       // Retry with subsume_loads == false
 882       // If this is the first failure, the sentinel string will "stick"
 883       // to the Compile object, and the C2Compiler will see it and retry.
 884       C->record_failure(C2Compiler::retry_no_subsuming_loads());


 902 
 903   return true;
 904 }
 905 
 906 //--------------------------catch_cleanup_fix_all_inputs-----------------------
 907 static void catch_cleanup_fix_all_inputs(Node *use, Node *old_def, Node *new_def) {
 908   for (uint l = 0; l < use->len(); l++) {
 909     if (use->in(l) == old_def) {
 910       if (l < use->req()) {
 911         use->set_req(l, new_def);
 912       } else {
 913         use->rm_prec(l);
 914         use->add_prec(new_def);
 915         l--;
 916       }
 917     }
 918   }
 919 }
 920 
 921 //------------------------------catch_cleanup_find_cloned_def------------------
 922 static Node *catch_cleanup_find_cloned_def(Block *use_blk, Node *def, Block *def_blk, PhaseCFG* cfg, int n_clone_idx) {
 923   assert( use_blk != def_blk, "Inter-block cleanup only");
 924 
 925   // The use is some block below the Catch.  Find and return the clone of the def
 926   // that dominates the use. If there is no clone in a dominating block, then
 927   // create a phi for the def in a dominating block.
 928 
 929   // Find which successor block dominates this use.  The successor
 930   // blocks must all be single-entry (from the Catch only; I will have
 931   // split blocks to make this so), hence they all dominate.
 932   while( use_blk->_dom_depth > def_blk->_dom_depth+1 )
 933     use_blk = use_blk->_idom;
 934 
 935   // Find the successor
 936   Node *fixup = NULL;
 937 
 938   uint j;
 939   for( j = 0; j < def_blk->_num_succs; j++ )
 940     if( use_blk == def_blk->_succs[j] )
 941       break;
 942 
 943   if( j == def_blk->_num_succs ) {
 944     // Block at same level in dom-tree is not a successor.  It needs a
 945     // PhiNode, the PhiNode uses from the def and IT's uses need fixup.
 946     Node_Array inputs = new Node_List(Thread::current()->resource_area());
 947     for(uint k = 1; k < use_blk->num_preds(); k++) {
 948       Block* block = cfg->get_block_for_node(use_blk->pred(k));
 949       inputs.map(k, catch_cleanup_find_cloned_def(block, def, def_blk, cfg, n_clone_idx));
 950     }
 951 
 952     // Check to see if the use_blk already has an identical phi inserted.
 953     // If it exists, it will be at the first position since all uses of a
 954     // def are processed together.
 955     Node *phi = use_blk->_nodes[1];
 956     if( phi->is_Phi() ) {
 957       fixup = phi;
 958       for (uint k = 1; k < use_blk->num_preds(); k++) {
 959         if (phi->in(k) != inputs[k]) {
 960           // Not a match
 961           fixup = NULL;
 962           break;
 963         }
 964       }
 965     }
 966 
 967     // If an existing PhiNode was not found, make a new one.
 968     if (fixup == NULL) {
 969       Node *new_phi = PhiNode::make(use_blk->head(), def);
 970       use_blk->_nodes.insert(1, new_phi);
 971       cfg->map_node_to_block(new_phi, use_blk);
 972       for (uint k = 1; k < use_blk->num_preds(); k++) {
 973         new_phi->set_req(k, inputs[k]);
 974       }
 975       fixup = new_phi;
 976     }
 977 
 978   } else {
 979     // Found the use just below the Catch.  Make it use the clone.
 980     fixup = use_blk->_nodes[n_clone_idx];
 981   }
 982 
 983   return fixup;
 984 }
 985 
 986 //--------------------------catch_cleanup_intra_block--------------------------
 987 // Fix all input edges in use that reference "def".  The use is in the same
 988 // block as the def and both have been cloned in each successor block.
 989 static void catch_cleanup_intra_block(Node *use, Node *def, Block *blk, int beg, int n_clone_idx) {
 990 
 991   // Both the use and def have been cloned. For each successor block,
 992   // get the clone of the use, and make its input the clone of the def
 993   // found in that block.
 994 
 995   uint use_idx = blk->find_node(use);
 996   uint offset_idx = use_idx - beg;
 997   for( uint k = 0; k < blk->_num_succs; k++ ) {
 998     // Get clone in each successor block
 999     Block *sb = blk->_succs[k];
1000     Node *clone = sb->_nodes[offset_idx+1];
1001     assert( clone->Opcode() == use->Opcode(), "" );
1002 
1003     // Make use-clone reference the def-clone
1004     catch_cleanup_fix_all_inputs(clone, def, sb->_nodes[n_clone_idx]);
1005   }
1006 }
1007 
1008 //------------------------------catch_cleanup_inter_block---------------------
1009 // Fix all input edges in use that reference "def".  The use is in a different
1010 // block than the def.
1011 static void catch_cleanup_inter_block(Node *use, Block *use_blk, Node *def, Block *def_blk, PhaseCFG* cfg, int n_clone_idx) {
1012   if( !use_blk ) return;        // Can happen if the use is a precedence edge
1013 
1014   Node *new_def = catch_cleanup_find_cloned_def(use_blk, def, def_blk, cfg, n_clone_idx);
1015   catch_cleanup_fix_all_inputs(use, def, new_def);
1016 }
1017 
1018 //------------------------------call_catch_cleanup-----------------------------
1019 // If we inserted any instructions between a Call and his CatchNode,
1020 // clone the instructions on all paths below the Catch.
1021 void Block::call_catch_cleanup(PhaseCFG* cfg, Compile* C) {
1022 
1023   // End of region to clone
1024   uint end = end_idx();
1025   if( !_nodes[end]->is_Catch() ) return;
1026   // Start of region to clone
1027   uint beg = end;
1028   while(!_nodes[beg-1]->is_MachProj() ||
1029         !_nodes[beg-1]->in(0)->is_MachCall() ) {
1030     beg--;
1031     assert(beg > 0,"Catch cleanup walking beyond block boundary");
1032   }
1033   // Range of inserted instructions is [beg, end)
1034   if( beg == end ) return;
1035 
1036   // Clone along all Catch output paths.  Clone area between the 'beg' and
1037   // 'end' indices.
1038   for( uint i = 0; i < _num_succs; i++ ) {
1039     Block *sb = _succs[i];
1040     // Clone the entire area; ignoring the edge fixup for now.
1041     for( uint j = end; j > beg; j-- ) {
1042       // It is safe here to clone a node with anti_dependence
1043       // since clones dominate on each path.
1044       Node *clone = _nodes[j-1]->clone();
1045       sb->_nodes.insert( 1, clone );
1046       cfg->map_node_to_block(clone, sb);
1047     }
1048   }
1049 
1050 
1051   // Fixup edges.  Check the def-use info per cloned Node
1052   for(uint i2 = beg; i2 < end; i2++ ) {
1053     uint n_clone_idx = i2-beg+1; // Index of clone of n in each successor block
1054     Node *n = _nodes[i2];        // Node that got cloned
1055     // Need DU safe iterator because of edge manipulation in calls.
1056     Unique_Node_List *out = new Unique_Node_List(Thread::current()->resource_area());
1057     for (DUIterator_Fast j1max, j1 = n->fast_outs(j1max); j1 < j1max; j1++) {
1058       out->push(n->fast_out(j1));
1059     }
1060     uint max = out->size();
1061     for (uint j = 0; j < max; j++) {// For all users
1062       Node *use = out->pop();
1063       Block *buse = cfg->get_block_for_node(use);
1064       if( use->is_Phi() ) {
1065         for( uint k = 1; k < use->req(); k++ )
1066           if( use->in(k) == n ) {
1067             Block* block = cfg->get_block_for_node(buse->pred(k));
1068             Node *fixup = catch_cleanup_find_cloned_def(block, n, this, cfg, n_clone_idx);
1069             use->set_req(k, fixup);
1070           }
1071       } else {
1072         if (this == buse) {
1073           catch_cleanup_intra_block(use, n, this, beg, n_clone_idx);
1074         } else {
1075           catch_cleanup_inter_block(use, buse, n, this, cfg, n_clone_idx);
1076         }
1077       }
1078     } // End for all users
1079 
1080   } // End of for all Nodes in cloned area
1081 
1082   // Remove the now-dead cloned ops
1083   for(uint i3 = beg; i3 < end; i3++ ) {
1084     _nodes[beg]->disconnect_inputs(NULL, C);
1085     _nodes.remove(beg);
1086   }
1087 
1088   // If the successor blocks have a CreateEx node, move it back to the top
1089   for(uint i4 = 0; i4 < _num_succs; i4++ ) {
1090     Block *sb = _succs[i4];
1091     uint new_cnt = end - beg;
1092     // Remove any newly created, but dead, nodes.
1093     for( uint j = new_cnt; j > 0; j-- ) {
1094       Node *n = sb->_nodes[j];
1095       if (n->outcnt() == 0 &&
src/share/vm/opto/lcm.cpp
Index Unified diffs Context diffs Sdiffs Patch New Old Previous File Next File