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/* Compensate for inconsistent structure return conventions on IRIX 6.  */
/* Compile this one with gcc.  */
/* Copyright (C) 2001  Free Software Foundation, Inc.

This file is part of GNU CC.

GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

In addition to the permissions in the GNU General Public License, the
Free Software Foundation gives you unlimited permission to link the
compiled version of this file into combinations with other programs,
and to distribute those combinations without any restriction coming
from the use of this file.  (The General Public License restrictions
do apply in other respects; for example, they cover modification of
the file, and distribution when not linked into a combine
executable.)

GNU CC 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

/* GCC doesn't correctly implement the structure and union return
   conventions of the N32 and N64 ABIs on IRIX 6, as described in the
   MIPSpro N32 ABI Handbook, ch. 2, Calling Convention Implementations, p.7.
   The ABI requires that structures (or trailing parts of structures) smaller
   than 8 bytes (a 64-bit register) are left-justified, whereas GCC
   right-justifies them.

   While GCC is internally consistent, calling routines compiled with a
   compiler that does implement the documented ABI (like SGIs MIPSpro C
   compiler) doesn't work.  This is primarily an issue for system libraries
   like libc.  Fortunately, there exist only very few routines that return
   structures by value, so until the underlying bug is fixed, it is possible
   to work around it by providing wrappers for the few affected routines.

   These wrappers rely on the fact that e.g. libc contains weak versions of
   those routines, and the real implementation is provided by _-prefixed
   variants.  So we can provide our own versions, which will only be linked
   if the application uses any of the affected functions, calling the private
   variants and then shifting the result as required.

   This is a rewrite of code created by Andy Polyakov.  */

#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"

/* This must only be used for the N32 and N64 ABIs.  O32 is correct.  */

#if _MIPS_SIM == _ABIN32 || _MIPS_SIM == _ABI64

/* The affected return values need to be shifted by

	BITS_PER_WORD - (sizeof (value) * BITS_PER_UNIT).

   Since only 32-bit results are involved, the shift count is always 32.  */
#define SHIFT_BITS	32

extern machreg_t _inet_makeaddr (machreg_t, machreg_t);

/* <arpa/inet.h> has

	struct in_addr inet_makeaddr (int, int);		(IRIX 6.2)
	struct in_addr inet_makeaddr (in_addr_t, in_addr_t);	(IRIX 6.5)  */

machreg_t
inet_makeaddr (machreg_t net, machreg_t lna)
{
  return _inet_makeaddr (net, lna) >> SHIFT_BITS;
}

#endif /* _ABIN32 || _ABI64 */