/*
* Copyright (c) 1983, 1993, 1998
*      The Regents of the University of California.  All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "gprof.h"
#include "search_list.h"
#include "source.h"
#include "symtab.h"
#include "cg_arcs.h"
#include "corefile.h"
#include "hist.h"

/*
* Opcodes of the call instructions:
*/
#define OP_Jxx  0x1aU
#define OP_BSR  0x34U

#define Jxx_FUNC_JMP            0U
#define Jxx_FUNC_JSR            1U
#define Jxx_FUNC_RET            2U
#define Jxx_FUNC_JSR_COROUTINE  3U

/* *INDENT-OFF* */
/* Here to document only.  We can't use this when cross compiling as
  the bitfield layout might not be the same as native.

  typedef union
    {
      struct
        {
          unsigned other:26;
          unsigned op_code:6;
        }
      a;                               -- any format
      struct
        {
          int disp:21;
          unsigned ra:5;
          unsigned op_code:6;
        }
      b;                               -- branch format
      struct
        {
          int hint:14;
          unsigned func:2;
          unsigned rb:5;
          unsigned ra:5;
          unsigned op_code:6;
        }
      j;                               -- jump format
    }
   alpha_Instruction;
*/
/* *INDENT-ON* */

static Sym indirect_child;

void alpha_find_call (Sym *, bfd_vma, bfd_vma);

/*
* On the Alpha we can only detect PC relative calls, which are
* usually generated for calls to functions within the same
* object file only.  This is still better than nothing, however.
* (In particular it should be possible to find functions that
*  potentially call integer division routines, for example.)
*/
void
alpha_find_call (Sym *parent, bfd_vma p_lowpc, bfd_vma p_highpc)
{
 bfd_vma pc, dest_pc;
 unsigned int insn;
 Sym *child;
 Sym_Table *symtab = get_symtab ();

 if (indirect_child.name == NULL)
   {
     sym_init (&indirect_child);
     indirect_child.name = _("<indirect child>");
     indirect_child.cg.prop.fract = 1.0;
     indirect_child.cg.cyc.head = &indirect_child;
   }

 DBG (CALLDEBUG, printf (_("[find_call] %s: 0x%lx to 0x%lx\n"),
                         parent->name, (unsigned long) p_lowpc,
                         (unsigned long) p_highpc));
 p_lowpc = (p_lowpc + 3) & ~3;
 p_highpc &= ~3;
 for (pc = p_lowpc; pc < p_highpc; pc += 4)
   {
     insn = bfd_get_32 (core_bfd, ((unsigned char *) core_text_space
                                   + pc - core_text_sect->vma));
     switch (insn & (0x3fU << 26))
       {
       case OP_Jxx << 26:
         /*
          * There is no simple and reliable way to determine the
          * target of a jsr (the hint bits help, but there aren't
          * enough bits to get a satisfactory hit rate).  Instead,
          * for any indirect jump we simply add an arc from PARENT
          * to INDIRECT_CHILD---that way the user it at least able
          * to see that there are other calls as well.
          */
         if ((insn & (3 << 14)) == Jxx_FUNC_JSR << 14
             || (insn & (3 << 14)) == Jxx_FUNC_JSR_COROUTINE << 14)
           {
             DBG (CALLDEBUG,
                  printf (_("[find_call] 0x%lx: jsr%s <indirect_child>\n"),
                          (unsigned long) pc,
                          ((insn & (3 << 14)) == Jxx_FUNC_JSR << 14
                           ? "" : "_coroutine")));
             arc_add (parent, &indirect_child, (unsigned long) 0);
           }
         break;

       case OP_BSR << 26:
         DBG (CALLDEBUG,
              printf (_("[find_call] 0x%lx: bsr"), (unsigned long) pc));
         /*
          * Regular PC relative addressing.  Check that this is the
          * address of a function.  The linker sometimes redirects
          * the entry point by 8 bytes to skip loading the global
          * pointer, so we allow for either address:
          */
         dest_pc = pc + 4 + (((bfd_signed_vma) (insn & 0x1fffff)
                              ^ 0x100000) - 0x100000);
         if (hist_check_address (dest_pc))
           {
             child = sym_lookup (symtab, dest_pc);
             if (child)
               {
                 DBG (CALLDEBUG,
                      printf (" 0x%lx\t; name=%s, addr=0x%lx",
                              (unsigned long) dest_pc, child->name,
                              (unsigned long) child->addr));
                 if (child->addr == dest_pc || child->addr == dest_pc - 8)
                   {
                     DBG (CALLDEBUG, printf ("\n"));
                     /* a hit:  */
                     arc_add (parent, child, (unsigned long) 0);
                     continue;
                   }
               }
           }
         /*
          * Something funny going on.
          */
         DBG (CALLDEBUG, printf ("\tbut it's a botch\n"));
         break;

       default:
         break;
       }
   }
}