src/share/vm/opto/loopTransform.cpp

*** 267,280 ****
  // Return TRUE or FALSE if the loop should be peeled or not.  Peel if we can
  // make some loop-invariant test (usually a null-check) happen before the loop.
  bool IdealLoopTree::policy_peeling( PhaseIdealLoop *phase ) const {
    Node *test = ((IdealLoopTree*)this)->tail();
    int  body_size = ((IdealLoopTree*)this)->_body.size();
-   int  live_node_count = phase->C->live_nodes();
    // Peeling does loop cloning which can result in O(N^2) node construction
    if( body_size > 255 /* Prevent overflow for large body_size */
!       || (body_size * body_size + live_node_count > MaxNodeLimit) ) {
      return false;           // too large to safely clone
    }
    while( test != _head ) {      // Scan till run off top of loop
      if( test->is_If() ) {       // Test?
        Node *ctrl = phase->get_ctrl(test->in(1));
--- 267,279 ----
  // Return TRUE or FALSE if the loop should be peeled or not.  Peel if we can
  // make some loop-invariant test (usually a null-check) happen before the loop.
  bool IdealLoopTree::policy_peeling( PhaseIdealLoop *phase ) const {
    Node *test = ((IdealLoopTree*)this)->tail();
    int  body_size = ((IdealLoopTree*)this)->_body.size();
    // Peeling does loop cloning which can result in O(N^2) node construction
    if( body_size > 255 /* Prevent overflow for large body_size */
!       || (body_size * body_size + phase->C->live_nodes()) > phase->C->max_node_limit() ) {
      return false;           // too large to safely clone
    }
    while( test != _head ) {      // Scan till run off top of loop
      if( test->is_If() ) {       // Test?
        Node *ctrl = phase->get_ctrl(test->in(1));
*** 599,609 ****
    uint tst_body_size = (new_body_size - EMPTY_LOOP_SIZE) / trip_count + EMPTY_LOOP_SIZE;
    if (body_size != tst_body_size) // Check for int overflow
      return false;
    if (new_body_size > unroll_limit ||
        // Unrolling can result in a large amount of node construction
!       new_body_size >= MaxNodeLimit - (uint) phase->C->live_nodes()) {
      return false;
    }
  
    // Do not unroll a loop with String intrinsics code.
    // String intrinsics are large and have loops.
--- 598,608 ----
    uint tst_body_size = (new_body_size - EMPTY_LOOP_SIZE) / trip_count + EMPTY_LOOP_SIZE;
    if (body_size != tst_body_size) // Check for int overflow
      return false;
    if (new_body_size > unroll_limit ||
        // Unrolling can result in a large amount of node construction
!       new_body_size >= phase->C->max_node_limit() - phase->C->live_nodes()) {
      return false;
    }
  
    // Do not unroll a loop with String intrinsics code.
    // String intrinsics are large and have loops.
*** 2285,2296 ****
      }
    }
  
    // Skip next optimizations if running low on nodes. Note that
    // policy_unswitching and policy_maximally_unroll have this check.
!   uint nodes_left = MaxNodeLimit - (uint) phase->C->live_nodes();
!   if ((2 * _body.size()) > nodes_left) {
      return true;
    }
  
    // Counted loops may be peeled, may need some iterations run up
    // front for RCE, and may want to align loop refs to a cache
--- 2284,2295 ----
      }
    }
  
    // Skip next optimizations if running low on nodes. Note that
    // policy_unswitching and policy_maximally_unroll have this check.
!   int nodes_left = phase->C->max_node_limit() - phase->C->live_nodes();
!   if ((int)(2 * _body.size()) > nodes_left) {
      return true;
    }
  
    // Counted loops may be peeled, may need some iterations run up
    // front for RCE, and may want to align loop refs to a cache