/* libunwind - a platform-independent unwind library

   Copyright (c) 2002-2004 Hewlett-Packard Development Company, L.P.

        Contributed by David Mosberger-Tang <davidm@hpl.hp.com>

   Modified for x86_64 by Max Asbock <masbock@us.ibm.com>

This file is part of libunwind.

Permission is hereby granted, free of charge, to any person obtaining

a copy of this software and associated documentation files (the

"Software"), to deal in the Software without restriction, including

without limitation the rights to use, copy, modify, merge, publish,

distribute, sublicense, and/or sell copies of the Software, and to

permit persons to whom the Software is furnished to do so, subject to

the following conditions:

The above copyright notice and this permission notice shall be

included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE

LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION

OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION

WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */

#include <stdlib.h>

#include "libunwind_i.h"

#include "unwind_i.h"

#ifndef UNW_REMOTE_ONLY

HIDDEN inline int

x86_64_local_resume (unw_addr_space_t as UNUSED, unw_cursor_t *cursor, void *arg UNUSED)

{

  struct cursor *c = (struct cursor *) cursor;

  ucontext_t *uc = dwarf_get_uc(&c->dwarf);

#if defined __CET__ && (__CET__ & 2) != 0

  uintptr_t frames = (uintptr_t) arg;

#endif

  /* Ensure c->pi is up-to-date.  On x86-64, it's relatively common to

     be missing DWARF unwind info.  We don't want to fail in that

     case, because the frame-chain still would let us do a backtrace

     at least.  */

  dwarf_make_proc_info (&c->dwarf);

  if (unlikely (c->sigcontext_addr != X86_64_SCF_NONE))

    {

      x86_64_sigreturn(cursor);

      abort();

    }

  else

    {

      Debug (8, "resuming at ip=%llx via setcontext()\n",

             (unsigned long long) c->dwarf.ip);

      POP_SHADOW_STACK_FRAMES (frames);

      setcontext (uc);

    }

  return -UNW_EINVAL;

}

#endif /* !UNW_REMOTE_ONLY */

/* This routine is responsible for copying the register values in

   cursor C and establishing them as the current machine state. */

static inline int

establish_machine_state (struct cursor *c)

{

  int (*access_reg) (unw_addr_space_t, unw_regnum_t, unw_word_t *,

                     int write, void *);

  int (*access_fpreg) (unw_addr_space_t, unw_regnum_t, unw_fpreg_t *,

                       int write, void *);

  unw_addr_space_t as = c->dwarf.as;

  void *arg = c->dwarf.as_arg;

  unw_fpreg_t fpval;

  unw_word_t val;

  int reg;

  access_reg = as->acc.access_reg;

  access_fpreg = as->acc.access_fpreg;

  Debug (8, "copying out cursor state\n");

  for (reg = 0; reg <= UNW_REG_LAST; ++reg)

    {

      Debug (16, "copying %s %d\n", unw_regname (reg), reg);

      if (unw_is_fpreg (reg))

        {

          if (tdep_access_fpreg (c, reg, &fpval, 0) >= 0)

            (*access_fpreg) (as, reg, &fpval, 1, arg);

        }

      else

        {

          if (tdep_access_reg (c, reg, &val, 0) >= 0)

            (*access_reg) (as, reg, &val, 1, arg);

        }

    }

  if (c->dwarf.args_size)

    {

      if (tdep_access_reg (c, UNW_X86_64_RSP, &val, 0) >= 0)

        {

          val += c->dwarf.args_size;

          (*access_reg) (as, UNW_X86_64_RSP, &val, 1, arg);

        }

    }

  return 0;

}

int

unw_resume (unw_cursor_t *cursor)

{

  struct cursor *c = (struct cursor *) cursor;

  int ret;

  Debug (1, "(cursor=%p)\n", c);

  if ((ret = establish_machine_state (c)) < 0)

    return ret;

  ret = (*c->dwarf.as->acc.resume) (c->dwarf.as, (unw_cursor_t *) c,

            (void *) c->frames);

#if defined __CET__ && (__CET__ & 2) != 0

  /* NB: Disable tail call when shadow stack is enabled so that

     _Ux86_64_setcontext can properly count the number of shadow

     stack frames to pop.  */

  __asm ("" ::: "memory");

#endif

  return ret;

}