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/* Copyright (C) 1998-2013 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

#include <stdlib.h>
#include <unistd.h>
#include <ldsodefs.h>
#include <sysdep.h>


int __cache_line_size attribute_hidden;
/* The main work is done in the generic function.  */
#define LIBC_START_MAIN generic_start_main
#define LIBC_START_DISABLE_INLINE
#define LIBC_START_MAIN_AUXVEC_ARG
#define MAIN_AUXVEC_ARG
#define INIT_MAIN_ARGS
#include <csu/libc-start.c>

struct startup_info
  {
    void *sda_base;
    int (*main) (int, char **, char **, void *);
    int (*init) (int, char **, char **, void *);
    void (*fini) (void);
  };

int
__libc_start_main (int argc, char **argv,
		   char **ev,
		   ElfW (auxv_t) * auxvec,
		   void (*rtld_fini) (void),
		   struct startup_info *stinfo,
		   char **stack_on_entry)
{
  /* the PPC SVR4 ABI says that the top thing on the stack will
     be a NULL pointer, so if not we assume that we're being called
     as a statically-linked program by Linux...  */
  if (*stack_on_entry != NULL)
    {
      char **temp;
      /* ...in which case, we have argc as the top thing on the
         stack, followed by argv (NULL-terminated), envp (likewise),
         and the auxilary vector.  */
      /* 32/64-bit agnostic load from stack */
      argc = *(long int *) stack_on_entry;
      argv = stack_on_entry + 1;
      ev = argv + argc + 1;
#ifdef HAVE_AUX_VECTOR
      temp = ev;
      while (*temp != NULL)
	++temp;
      auxvec = (ElfW (auxv_t) *)++ temp;
#endif
      rtld_fini = NULL;
    }

  /* Initialize the __cache_line_size variable from the aux vector.
     This is used by memset to optimize setting to zero.  We have to
     detect 8xx processors, which have buggy dcbz implementations that
     cannot report page faults correctly.  That requires reading SPR,
     which is a privileged operation.  Fortunately 2.2.18 and later
     emulates PowerPC mfspr reads from the PVR register.  */
  for (ElfW (auxv_t) * av = auxvec; av->a_type != AT_NULL; ++av)
    switch (av->a_type)
      {
      case AT_DCACHEBSIZE:
	if (__LINUX_KERNEL_VERSION >= 0x020218)
	  {
	    unsigned pvr = 0;
	    
	    asm ("mfspr %0, 287" : "=r" (pvr) :);
	    if ((pvr & 0xffff0000) == 0x00500000)
	      break;
	  }
	__cache_line_size = av->a_un.a_val;
	break;
      }

  return generic_start_main (stinfo->main, argc, argv, auxvec,
			     stinfo->init, stinfo->fini, rtld_fini,
			     stack_on_entry);
}