src/share/vm/opto/phaseX.cpp

*** 1,7 ****
  /*
!  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
--- 1,7 ----
  /*
!  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
*** 1414,1423 ****
--- 1414,1444 ----
    for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
      _worklist.push(n->fast_out(i));  // Push on worklist
    }
  }
  
+ // Return counted loop Phi if as a counted loop exit condition, cmp
+ // compares the the induction variable with n
+ static PhiNode* countedloop_phi_from_cmp(CmpINode* cmp, Node* n) {
+   for (DUIterator_Fast imax, i = cmp->fast_outs(imax); i < imax; i++) {
+     Node* bol = cmp->fast_out(i);
+     for (DUIterator_Fast i2max, i2 = bol->fast_outs(i2max); i2 < i2max; i2++) {
+       Node* iff = bol->fast_out(i2);
+       if (iff->is_CountedLoopEnd()) {
+         CountedLoopEndNode* cle = iff->as_CountedLoopEnd();
+         if (cle->limit() == n) {
+           PhiNode* phi = cle->phi();
+           if (phi != NULL) {
+             return phi;
+           }
+         }
+       }
+     }
+   }
+   return NULL;
+ }
+ 
  void PhaseIterGVN::add_users_to_worklist( Node *n ) {
    add_users_to_worklist0(n);
  
    // Move users of node to worklist
    for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
*** 1443,1464 ****
        add_users_to_worklist(use); // Put Bool on worklist
        if (use->outcnt() > 0) {
          Node* bol = use->raw_out(0);
          if (bol->outcnt() > 0) {
            Node* iff = bol->raw_out(0);
!           if (use_op == Op_CmpI &&
!               iff->is_CountedLoopEnd()) {
!             CountedLoopEndNode* cle = iff->as_CountedLoopEnd();
!             if (cle->limit() == n && cle->phi() != NULL) {
!               // If an opaque node feeds into the limit condition of a
!               // CountedLoop, we need to process the Phi node for the
!               // induction variable when the opaque node is removed:
!               // the range of values taken by the Phi is now known and
!               // so its type is also known.
!               _worklist.push(cle->phi());
!             }
!           } else if (iff->outcnt() == 2) {
              // Look for the 'is_x2logic' pattern: "x ? : 0 : 1" and put the
              // phi merging either 0 or 1 onto the worklist
              Node* ifproj0 = iff->raw_out(0);
              Node* ifproj1 = iff->raw_out(1);
              if (ifproj0->outcnt() > 0 && ifproj1->outcnt() > 0) {
--- 1464,1474 ----
        add_users_to_worklist(use); // Put Bool on worklist
        if (use->outcnt() > 0) {
          Node* bol = use->raw_out(0);
          if (bol->outcnt() > 0) {
            Node* iff = bol->raw_out(0);
!           if (iff->outcnt() == 2) {
              // Look for the 'is_x2logic' pattern: "x ? : 0 : 1" and put the
              // phi merging either 0 or 1 onto the worklist
              Node* ifproj0 = iff->raw_out(0);
              Node* ifproj1 = iff->raw_out(1);
              if (ifproj0->outcnt() > 0 && ifproj1->outcnt() > 0) {
*** 1469,1478 ****
--- 1479,1497 ----
              }
            }
          }
        }
        if (use_op == Op_CmpI) {
+         Node* phi = countedloop_phi_from_cmp((CmpINode*)use, n);
+         if (phi != NULL) {
+           // If an opaque node feeds into the limit condition of a
+           // CountedLoop, we need to process the Phi node for the
+           // induction variable when the opaque node is removed:
+           // the range of values taken by the Phi is now known and
+           // so its type is also known.
+           _worklist.push(phi);
+         }
          Node* in1 = use->in(1);
          for (uint i = 0; i < in1->outcnt(); i++) {
            if (in1->raw_out(i)->Opcode() == Op_CastII) {
              Node* castii = in1->raw_out(i);
              if (castii->in(0) != NULL && castii->in(0)->in(0) != NULL && castii->in(0)->in(0)->is_If()) {
*** 1657,1666 ****
--- 1676,1694 ----
                  worklist.push(p); // Propagate change to user
                }
              }
            }
          }
+         // If n is used in a counted loop exit condition then the type
+         // of the counted loop's Phi depends on the type of n. See
+         // PhiNode::Value().
+         if (m_op == Op_CmpI) {
+           PhiNode* phi = countedloop_phi_from_cmp((CmpINode*)m, n);
+           if (phi != NULL) {
+             worklist.push(phi);
+           }
+         }
        }
      }
    }
  }