示例#1
0
void* ponyint_heap_realloc(pony_actor_t* actor, heap_t* heap, void* p,
  size_t size)
{
  if(p == NULL)
    return ponyint_heap_alloc(actor, heap, size);

  chunk_t* chunk = (chunk_t*)ponyint_pagemap_get(p);

  if(chunk == NULL)
  {
    // Get new memory and copy from the old memory.
    void* q = ponyint_heap_alloc(actor, heap, size);
    memcpy(q, p, size);
    return q;
  }

  size_t oldsize;

  if(chunk->size < HEAP_SIZECLASSES)
  {
    // Previous allocation was a ponyint_heap_alloc_small.
    void* ext = EXTERNAL_PTR(p, chunk->size);

    // If the new allocation is a ponyint_heap_alloc_small and the pointer is
    // not an internal pointer, we may be able to reuse this memory. If it is
    // an internal pointer, we know where the old allocation begins but not
    // where it ends, so we cannot reuse this memory.
    if((size <= HEAP_MAX) && (p == ext))
    {
      uint32_t sizeclass = ponyint_heap_index(size);

      // If the new allocation is the same size or smaller, return the old
      // one.
      if(sizeclass <= chunk->size)
        return p;
    }

    oldsize = SIZECLASS_SIZE(chunk->size) - ((uintptr_t)p - (uintptr_t)ext);
  } else {
    // Previous allocation was a ponyint_heap_alloc_large.
    if((size <= chunk->size) && (p == chunk->m))
    {
      // If the new allocation is the same size or smaller, and this is not an
      // internal pointer, return the old one. We can't reuse internal
      // pointers in large allocs for the same reason as small ones.
      return p;
    }

    oldsize = chunk->size - ((uintptr_t)p - (uintptr_t)chunk->m);
  }

  // Determine how much memory to copy.
  if(oldsize > size)
    oldsize = size;

  // Get new memory and copy from the old memory.
  void* q = ponyint_heap_alloc(actor, heap, size);
  memcpy(q, p, oldsize);
  return q;
}
示例#2
0
文件: heap.c 项目: JamesLinus/ponyc
void* ponyint_heap_realloc(pony_actor_t* actor, heap_t* heap, void* p,
  size_t size)
{
  if(p == NULL)
    return ponyint_heap_alloc(actor, heap, size);

  chunk_t* chunk = (chunk_t*)ponyint_pagemap_get(p);

  if(chunk == NULL)
  {
    // Get new memory and copy from the old memory.
    void* q = ponyint_heap_alloc(actor, heap, size);
    memcpy(q, p, size);
    return q;
  }

  if(chunk->size < HEAP_SIZECLASSES)
  {
    // Previous allocation was a ponyint_heap_alloc_small.
    if(size <= HEAP_MAX)
    {
      uint32_t sizeclass = ponyint_heap_index(size);

      // If the new allocation is the same size or smaller, return the old one.
      if(sizeclass <= chunk->size)
        return p;
    }

    // Get new memory and copy from the old memory.
    void* q = ponyint_heap_alloc(actor, heap, size);
    memcpy(q, p, SIZECLASS_SIZE(chunk->size));
    return q;
  }

  // Previous allocation was a ponyint_heap_alloc_large.
  if(size <= chunk->size)
    return p;

  // Get new memory and copy from the old memory.
  void* q = ponyint_heap_alloc(actor, heap, size);
  memcpy(q, p, chunk->size);
  return q;
}