src/share/vm/opto/memnode.cpp

rev 8052 : castpp gcm
rev 8568 : 8086046: escape analysis generates incorrect code as of B67
Summary: load bypasses arraycopy that sets the value after the ArrayCopyNode is expanded
Reviewed-by:

*** 106,138 ****
  
  extern void print_alias_types();
  
  #endif
  
! static bool membar_for_arraycopy_helper(const TypeOopPtr *t_oop, MergeMemNode* mm, PhaseTransform *phase) {
!   if (mm->memory_at(Compile::AliasIdxRaw)->is_Proj()) {
!     Node* n = mm->memory_at(Compile::AliasIdxRaw)->in(0);
!     if ((n->is_ArrayCopy() && n->as_ArrayCopy()->may_modify(t_oop, phase)) ||
!         (n->is_CallLeaf() && n->as_CallLeaf()->may_modify(t_oop, phase))) {
        return true;
      }
    }
    return false;
  }
  
  static bool membar_for_arraycopy(const TypeOopPtr *t_oop, MemBarNode* mb, PhaseTransform *phase) {
    Node* mem = mb->in(TypeFunc::Memory);
    if (mem->is_MergeMem()) {
!     return membar_for_arraycopy_helper(t_oop, mem->as_MergeMem(), phase);
!   } else if (mem->is_Phi()) {
!     // after macro expansion of an ArrayCopyNode we may have a Phi
!     for (uint i = 1; i < mem->req(); i++) {
!       if (mem->in(i) != NULL && mem->in(i)->is_MergeMem() && membar_for_arraycopy_helper(t_oop, mem->in(i)->as_MergeMem(), phase)) {
          return true;
        }
      }
    }
    return false;
  }
  
  Node *MemNode::optimize_simple_memory_chain(Node *mchain, const TypeOopPtr *t_oop, Node *load, PhaseGVN *phase) {
    assert((t_oop != NULL), "sanity");
--- 106,143 ----
  
  extern void print_alias_types();
  
  #endif
  
! static bool membar_for_arraycopy_helper(const TypeOopPtr *t_oop, Node* n, PhaseTransform *phase) {
!   if (n->is_Proj()) {
!     n = n->in(0);
!     if (n->is_Call() && n->as_Call()->may_modify(t_oop, phase)) {
        return true;
      }
    }
    return false;
  }
  
  static bool membar_for_arraycopy(const TypeOopPtr *t_oop, MemBarNode* mb, PhaseTransform *phase) {
    Node* mem = mb->in(TypeFunc::Memory);
+ 
    if (mem->is_MergeMem()) {
!     Node* n = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
!     if (membar_for_arraycopy_helper(t_oop, n, phase)) {
!       return true;
!     } else if (n->is_Phi()) {
!       for (uint i = 1; i < n->req(); i++) {
!         if (n->in(i) != NULL) {
!           if (membar_for_arraycopy_helper(t_oop, n->in(i), phase)) {
              return true;
            }
          }
        }
+     }
+   }
+   
    return false;
  }
  
  Node *MemNode::optimize_simple_memory_chain(Node *mchain, const TypeOopPtr *t_oop, Node *load, PhaseGVN *phase) {
    assert((t_oop != NULL), "sanity");