RFR: JDK-8202776: Modularize GC allocations in runtime

[Aleksey Shipilev]

On 06/04/2018 05:29 PM, Erik Österlund wrote:
>>> I agree the GC should be able to perform arbitrary allocations the way
>>> it wants to.
>>> However, I would prefer to do it this way:
>>> http://cr.openjdk.java.net/~eosterlund/8202776/webrev.00/

This looks good. I think we better hide mem_allocate under "protected" now, so we would have:

protected:
   // TLAB path
   inline static HeapWord* allocate_from_tlab(Klass* klass, size_t size, TRAPS);
   static HeapWord* allocate_from_tlab_slow(Klass* klass, size_t size, TRAPS);

   // Out-of-TLAB path
   virtual HeapWord* mem_allocate(size_t size,
                                  bool* gc_overhead_limit_was_exceeded) = 0;

public:
   // Entry point
   virtual HeapWord* obj_allocate_raw(Klass* klass, size_t size,
                                      bool* gc_overhead_limit_was_exceeded, TRAPS);

-Aleksey