text: /* Alloc.c -- Memory allocation functions
  2015-02-21 : Igor Pavlov : Public domain */
  
  #include "Precomp.h"
  
  #ifdef _WIN32
  #include <windows.h>
  #endif
  #include <stdlib.h>
  
  #include "Alloc.h"
  
  /* #define _SZ_ALLOC_DEBUG */
  
  /* use _SZ_ALLOC_DEBUG to debug alloc/free operations */
  #ifdef _SZ_ALLOC_DEBUG
  #include <stdio.h>
  int g_allocCount = 0;
  int g_allocCountMid = 0;
  int g_allocCountBig = 0;
  #endif
  
  void *MyAlloc(size_t size)
  {
    if (size == 0)
      return 0;
    #ifdef _SZ_ALLOC_DEBUG
    {
      void *p = malloc(size);
      fprintf(stderr, "\nAlloc %10d bytes, count = %10d,  addr = %8X", size, g_allocCount++, (unsigned)p);
      return p;
    }
    #else
    return malloc(size);
    #endif
  }
  
  void MyFree(void *address)
  {
    #ifdef _SZ_ALLOC_DEBUG
    if (address != 0)
      fprintf(stderr, "\nFree; count = %10d,  addr = %8X", --g_allocCount, (unsigned)address);
    #endif
    free(address);
  }
  
  #ifdef _WIN32
  
  void *MidAlloc(size_t size)
  {
    if (size == 0)
      return 0;
    #ifdef _SZ_ALLOC_DEBUG
    fprintf(stderr, "\nAlloc_Mid %10d bytes;  count = %10d", size, g_allocCountMid++);
    #endif
    return VirtualAlloc(0, size, MEM_COMMIT, PAGE_READWRITE);
  }
  
  void MidFree(void *address)
  {
    #ifdef _SZ_ALLOC_DEBUG
    if (address != 0)
      fprintf(stderr, "\nFree_Mid; count = %10d", --g_allocCountMid);
    #endif
    if (address == 0)
      return;
    VirtualFree(address, 0, MEM_RELEASE);
  }
  
  #ifndef MEM_LARGE_PAGES
  #undef _7ZIP_LARGE_PAGES
  #endif
  
  #ifdef _7ZIP_LARGE_PAGES
  SIZE_T g_LargePageSize = 0;
  typedef SIZE_T (WINAPI *GetLargePageMinimumP)();
  #endif
  
  void SetLargePageSize()
  {
    #ifdef _7ZIP_LARGE_PAGES
    SIZE_T size = 0;
    GetLargePageMinimumP largePageMinimum = (GetLargePageMinimumP)
          GetProcAddress(GetModuleHandle(TEXT("kernel32.dll")), "GetLargePageMinimum");
    if (largePageMinimum == 0)
      return;
    size = largePageMinimum();
    if (size == 0 || (size & (size - 1)) != 0)
      return;
    g_LargePageSize = size;
    #endif
  }
  
  
  void *BigAlloc(size_t size)
  {
    if (size == 0)
      return 0;
    #ifdef _SZ_ALLOC_DEBUG
    fprintf(stderr, "\nAlloc_Big %10d bytes;  count = %10d", size, g_allocCountBig++);
    #endif
  
    #ifdef _7ZIP_LARGE_PAGES
    if (g_LargePageSize != 0 && g_LargePageSize <= (1 << 30) && size >= (1 << 18))
    {
      void *res = VirtualAlloc(0, (size + g_LargePageSize - 1) & (~(g_LargePageSize - 1)),
          MEM_COMMIT | MEM_LARGE_PAGES, PAGE_READWRITE);
      if (res != 0)
        return res;
    }
    #endif
    return VirtualAlloc(0, size, MEM_COMMIT, PAGE_READWRITE);
  }
  
  void BigFree(void *address)
  {
    #ifdef _SZ_ALLOC_DEBUG
    if (address != 0)
      fprintf(stderr, "\nFree_Big; count = %10d", --g_allocCountBig);
    #endif
  
    if (address == 0)
      return;
    VirtualFree(address, 0, MEM_RELEASE);
  }
  
  #endif
  
  
  static void *SzAlloc(void *p, size_t size) { UNUSED_VAR(p); return MyAlloc(size); }
  static void SzFree(void *p, void *address) { UNUSED_VAR(p); MyFree(address); }
  ISzAlloc g_Alloc = { SzAlloc, SzFree };
  
  static void *SzBigAlloc(void *p, size_t size) { UNUSED_VAR(p); return BigAlloc(size); }
  static void SzBigFree(void *p, void *address) { UNUSED_VAR(p); BigFree(address); }
  ISzAlloc g_BigAlloc = { SzBigAlloc, SzBigFree };
  