coregrind/m_libcsetjmp.c

/*--------------------------------------------------------------------*/
/*--- A minimal setjmp/longjmp implementation.      m_libcsetjmp.c ---*/
/*--------------------------------------------------------------------*/
 
/*
   This file is part of Valgrind, a dynamic binary instrumentation
   framework.

   Copyright (C) 2010-2010 Mozilla Inc

   This program 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 of the
   License, or (at your option) any later version.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307, USA.

   The GNU General Public License is contained in the file COPYING.
*/

/* Contributed by Julian Seward <jseward@acm.org> */


#include "pub_core_basics.h"
#include "pub_core_libcsetjmp.h"    /* self */


/* See include/pub_tool_libcsetjmp.h for background and rationale. */

/* The only alternative implementations are for ppc{32,64}-linux.  See
   #259977. */

#if defined(VGP_ppc32_linux)

__asm__(
".text"  "\n"
""  "\n"
".global VG_MINIMAL_SETJMP"  "\n"  // r3 = jmp_buf
"VG_MINIMAL_SETJMP:"  "\n"
"        stw     0, 0(3)"  "\n"
"        stw     1, 4(3)"  "\n"
"        stw     2, 8(3)"  "\n"
"        stw     3, 12(3)"  "\n"
"        stw     4, 16(3)"  "\n"
"        stw     5, 20(3)"  "\n"
"        stw     6, 24(3)"  "\n"
"        stw     7, 28(3)"  "\n"
"        stw     8, 32(3)"  "\n"
"        stw     9, 36(3)"  "\n"
"        stw     10, 40(3)"  "\n"
"        stw     11, 44(3)"  "\n"
"        stw     12, 48(3)"  "\n"
"        stw     13, 52(3)"  "\n"
"        stw     14, 56(3)"  "\n"
"        stw     15, 60(3)"  "\n"
"        stw     16, 64(3)"  "\n"
"        stw     17, 68(3)"  "\n"
"        stw     18, 72(3)"  "\n"
"        stw     19, 76(3)"  "\n"
"        stw     20, 80(3)"  "\n"
"        stw     21, 84(3)"  "\n"
"        stw     22, 88(3)"  "\n"
"        stw     23, 92(3)"  "\n"
"        stw     24, 96(3)"  "\n"
"        stw     25, 100(3)"  "\n"
"        stw     26, 104(3)"  "\n"
"        stw     27, 108(3)"  "\n"
"        stw     28, 112(3)"  "\n"
"        stw     29, 116(3)"  "\n"
"        stw     30, 120(3)"  "\n"
"        stw     31, 124(3)"  "\n"
         // must use a caller-save register here as scratch, hence r4
"        mflr    4"  "\n"
"        stw     4, 128(3)"  "\n"
"        mfcr    4"  "\n"
"        stw     4, 132(3)"  "\n"
"        li      3, 0"  "\n"
"        blr"  "\n"
""  "\n"


".global VG_MINIMAL_LONGJMP"  "\n"
"VG_MINIMAL_LONGJMP:"  "\n"    // r3 = jmp_buf
         // do r4 = 1
         // and park it in the restore slot for r3 (the ret reg)
"        li      4, 1"  "\n"
"        stw     4, 12(3)"  "\n"
         // restore everything except r3
         // then r3 last of all
         // then blr
"        lwz     0, 128(3)"  "\n"
"        mtlr    0"  "\n"
"        lwz     0, 132(3)"  "\n"
"        mtcr    0"  "\n"
"        lwz     0, 0(3)"  "\n"
"        lwz     1, 4(3)"  "\n"
"        lwz     2, 8(3)"  "\n"
         // r3 is done at the end
"        lwz     4, 16(3)"  "\n"
"        lwz     5, 20(3)"  "\n"
"        lwz     6, 24(3)"  "\n"
"        lwz     7, 28(3)"  "\n"
"        lwz     8, 32(3)"  "\n"
"        lwz     9, 36(3)"  "\n"
"        lwz     10, 40(3)"  "\n"
"        lwz     11, 44(3)"  "\n"
"        lwz     12, 48(3)"  "\n"
"        lwz     13, 52(3)"  "\n"
"        lwz     14, 56(3)"  "\n"
"        lwz     15, 60(3)"  "\n"
"        lwz     16, 64(3)"  "\n"
"        lwz     17, 68(3)"  "\n"
"        lwz     18, 72(3)"  "\n"
"        lwz     19, 76(3)"  "\n"
"        lwz     20, 80(3)"  "\n"
"        lwz     21, 84(3)"  "\n"
"        lwz     22, 88(3)"  "\n"
"        lwz     23, 92(3)"  "\n"
"        lwz     24, 96(3)"  "\n"
"        lwz     25, 100(3)"  "\n"
"        lwz     26, 104(3)"  "\n"
"        lwz     27, 108(3)"  "\n"
"        lwz     28, 112(3)"  "\n"
"        lwz     29, 116(3)"  "\n"
"        lwz     30, 120(3)"  "\n"
"        lwz     31, 124(3)"  "\n"
"        lwz     3, 12(3)"  "\n"
"        blr"  "\n"
""  "\n"


".previous"  "\n"
);

#endif /* VGP_ppc32_linux */


/*--------------------------------------------------------------------*/
/*--- end                                                          ---*/
/*--------------------------------------------------------------------*/