src/hotspot/share/opto/block.hpp

@@ -51,11 +51,17 @@
    DEBUG_ONLY(uint _limit;)      // limit to formal domain
    Arena *_arena;                // Arena to allocate in
    ReallocMark _nesting;         // Safety checks for arena reallocation
  protected:
    Block **_blocks;
-   void grow( uint i );          // Grow array node to fit
+   void maybe_grow(uint i) {
+     _nesting.check(_arena);     // Check if a potential reallocation in the arena is safe
+     if (i >= Max()) {
+       grow(i);
+     }
+   }
+   void grow(uint i);            // Grow array node to fit
  
  public:
    Block_Array(Arena *a) : _size(OptoBlockListSize), _arena(a) {
      DEBUG_ONLY(_limit=0);
      _blocks = NEW_ARENA_ARRAY( a, Block *, OptoBlockListSize );

@@ -66,11 +72,11 @@
    Block *lookup( uint i ) const // Lookup, or null for not mapped
    { return (i<Max()) ? _blocks[i] : (Block*)nullptr; }
    Block *operator[] ( uint i ) const // Lookup, or assert for not mapped
    { assert( i < Max(), "oob" ); return _blocks[i]; }
    // Extend the mapping: index i maps to Block *n.
-   void map( uint i, Block *n ) { grow(i); _blocks[i] = n; }
+   void map( uint i, Block *n ) { maybe_grow(i); _blocks[i] = n; }
    uint Max() const { DEBUG_ONLY(return _limit); return _size; }
  };
  
  
  class Block_List : public Block_Array {