src/share/vm/opto/graphKit.cpp

rev 5411 : 8024069: replace_in_map() should operate on parent maps
Summary: type information gets lost because replace_in_map() doesn't update parent maps
Reviewed-by:
rev 5412 : imported patch replaceinmapparents-drop
rev 5413 : [mq]: replaceinmapparents-cleanup

*** 637,646 ****
--- 637,647 ----
    debug_only(kit->verify_map());
    _kit    = kit;
    _map    = kit->map();   // preserve the map
    _sp     = kit->sp();
    kit->set_map(clone_map ? kit->clone_map() : NULL);
+   Compile::current()->inc_preserve_jvm_state();
  #ifdef ASSERT
    _bci    = kit->bci();
    Parse* parser = kit->is_Parse();
    int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
    _block  = block;
*** 654,663 ****
--- 655,665 ----
    int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
    assert(block == _block,    "block must not shift");
  #endif
    kit->set_map(_map);
    kit->set_sp(_sp);
+   Compile::current()->dec_preserve_jvm_state();
  }
  
  
  //-----------------------------BuildCutout-------------------------------------
  BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
*** 1371,1391 ****
  }
  
  
  //--------------------------replace_in_map-------------------------------------
  void GraphKit::replace_in_map(Node* old, Node* neww) {
!   this->map()->replace_edge(old, neww);
  
    // Note: This operation potentially replaces any edge
    // on the map.  This includes locals, stack, and monitors
    // of the current (innermost) JVM state.
  
!   // We can consider replacing in caller maps.
!   // The idea would be that an inlined function's null checks
!   // can be shared with the entire inlining tree.
!   // The expense of doing this is that the PreserveJVMState class
!   // would have to preserve caller states too, with a deep copy.
  }
  
  
  //=============================================================================
  //--------------------------------memory---------------------------------------
--- 1373,1446 ----
  }
  
  
  //--------------------------replace_in_map-------------------------------------
  void GraphKit::replace_in_map(Node* old, Node* neww) {
!   if (old == neww) {
!     return;
!   }
! 
!   map()->replace_edge(old, neww);
  
    // Note: This operation potentially replaces any edge
    // on the map.  This includes locals, stack, and monitors
    // of the current (innermost) JVM state.
  
!   // PreserveJVMState doesn't do a deep copy so we can't modify
!   // parents
!   if (Compile::current()->has_preserve_jvm_state()) {
!     return;
!   }
! 
!   Parse* parser = is_Parse();
!   if (parser == NULL) {
!     parser = parent_parser();
!   }
! 
!   bool progress = true;
!   Node* ctrl = map()->in(0);
!   // Follow the chain of parsers and see whether the update can be
!   // done in the map of callers. We can do the replace for a caller if
!   // the current control post dominates the control of a caller.
!   while (parser != NULL && parser->jvms()->caller() != NULL && progress) {
!     progress = false;
!     Node* parent_map = parser->jvms()->caller()->map();
!     assert(parser->exits().map()->jvms()->depth() == parser->jvms()->caller()->depth(), "map mismatch");
! 
!     Node* parent_ctrl = parent_map->in(0);
!     
!     while (parent_ctrl->is_Region()) {
!       Node* n = parent_ctrl->as_Region()->is_copy();
!       if (n == NULL) {
!         break;
!       }
!       parent_ctrl = n;
!     }
!     
!     for (;;) {
!       if (ctrl == parent_ctrl) {
!         // update the map of the exits which is the one that will be
!         // used when compilation resume after inlining
!         parser->exits().map()->replace_edge(old, neww);
!         progress = true;
!         break;
!       }
!       if (ctrl->is_Proj() && ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none)) {
!         ctrl = ctrl->in(0)->in(0);
!       } else if (ctrl->is_Region()) {
!         Node* n = ctrl->as_Region()->is_copy();
!         if (n == NULL) {
!           break;
!         }
!         ctrl = n;
!       } else {
!         break;
!       }
!     }
! 
!     parser = parser->parent_parser();
!   }
  }
  
  
  //=============================================================================
  //--------------------------------memory---------------------------------------