Subversion Repositories openrisc_2011-10-31

/* Instruction printing code for the OpenRISC 1000

   Copyright (C) 2002, 2005, 2007 Free Software Foundation, Inc.

   Contributed by Damjan Lampret <lampret@opencores.org>.

   Modified from a29k port.

   This file is part of the GNU opcodes library.

   This library 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 3, or (at your option)

   any later version.

   It 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., 51 Franklin Street - Fifth Floor, Boston,

   MA 02110-1301, USA.  */

#define DEBUG 0

#include "dis-asm.h"

#include "or32.h"

//#include "safe-ctype.h"

#include <ctype.h>

#include <string.h>

#include <stdlib.h>

#include <stdio.h>

#define EXTEND28(x) ((x) & (unsigned long) 0x08000000 ? ((x) | (unsigned long) 0xf0000000) : ((x)))

/* Now find the four bytes of INSN_CH and put them in *INSN.  */

static void

find_bytes_big (unsigned char *insn_ch, unsigned long *insn)

{

  *insn =

    ((unsigned long) insn_ch[0] << 24) +

    ((unsigned long) insn_ch[1] << 16) +

    ((unsigned long) insn_ch[2] << 8) +

    ((unsigned long) insn_ch[3]);

#if DEBUG

  printf ("find_bytes_big3: %x\n", *insn);

#endif

}

static void

find_bytes_little (unsigned char *insn_ch, unsigned long *insn)

{

  *insn =

    ((unsigned long) insn_ch[3] << 24) +

    ((unsigned long) insn_ch[2] << 16) +

    ((unsigned long) insn_ch[1] << 8) +

    ((unsigned long) insn_ch[0]);

}

typedef void (*find_byte_func_type) (unsigned char *, unsigned long *);

static unsigned long

or32_extract (char param_ch, char *enc_initial, unsigned long insn)

{

  char *enc;

  unsigned long ret = 0;

  int opc_pos = 0;

  int param_pos = 0;

  for (enc = enc_initial; *enc != '\0'; enc++)

    if (*enc == param_ch)

      {

        if (enc - 2 >= enc_initial && (*(enc - 2) == '0') && (*(enc - 1) == 'x'))

          continue;

        else

          param_pos++;

      }

#if DEBUG

  printf ("or32_extract: %c %x ", param_ch, param_pos);

#endif

  opc_pos = 32;

  for (enc = enc_initial; *enc != '\0'; )

    if ((*enc == '0') && (*(enc + 1) == 'x'))

      {

        opc_pos -= 4;

        if ((param_ch == '0') || (param_ch == '1'))

          {

            unsigned long tmp = strtoul (enc, NULL, 16);

#if DEBUG

            printf (" enc=%s, tmp=%x ", enc, tmp);

#endif

            if (param_ch == '0')

              tmp = 15 - tmp;

            ret |= tmp << opc_pos;

          }

        enc += 3;

      }

    else if ((*enc == '0') || (*enc == '1'))

      {

        opc_pos--;

        if (param_ch == *enc)

          ret |= 1 << opc_pos;

        enc++;

      }

    else if (*enc == param_ch)

      {

        opc_pos--;

        param_pos--;

#if DEBUG

        printf ("\n  ret=%x opc_pos=%x, param_pos=%x\n", ret, opc_pos, param_pos);

#endif

        ret += ((insn >> opc_pos) & 0x1) << param_pos;

        if (!param_pos

            && letter_signed (param_ch)

            && ret >> (letter_range (param_ch) - 1))

          {

#if DEBUG

            printf ("\n  ret=%x opc_pos=%x, param_pos=%x\n",

                    ret, opc_pos, param_pos);

#endif

            ret |= 0xffffffff << letter_range(param_ch);

#if DEBUG

            printf ("\n  after conversion to signed: ret=%x\n", ret);

#endif

          }

        enc++;

      }

  //else if (ISALPHA (*enc))

  else if (isalpha(*enc))

      {

        opc_pos--;

        enc++;

      }

    else if (*enc == '-')

      {

        opc_pos--;

        enc++;

      }

    else

      enc++;

#if DEBUG

  printf ("ret=%x\n", ret);

#endif

  return ret;

}

static int

or32_opcode_match (unsigned long insn, char *encoding)

{

  unsigned long ones, zeros;

#if DEBUG

  printf ("or32_opcode_match: %.8lx\n", insn);

#endif    

  ones  = or32_extract ('1', encoding, insn);

  zeros = or32_extract ('0', encoding, insn);

  // Added 090430 - jb - fixed problem where upper 4 bytes of a 64-bit long weren't getting setup properly for comparison

  // As a result, instructions weren't getting decoded properly

  insn &= 0xffffffff;

  ones &= 0xffffffff;

  zeros &= 0xffffffff;

#if DEBUG

  printf ("ones: %x \n", ones);

  printf ("zeros: %x \n", zeros);

#endif

  if ((insn & ones) != ones)

    {

#if DEBUG

      printf ("ret1\n");

#endif

      return 0;

    }

  if ((~insn & zeros) != zeros)

    {

#if DEBUG

      printf ("ret2\n");

#endif

      return 0;

    }

#if DEBUG

  printf ("ret3\n");

#endif

  return 1;

}

/* Print register to INFO->STREAM. Used only by print_insn.  */

static void

or32_print_register (char param_ch,

                     char *encoding,

                     unsigned long insn)

                     //              struct disassemble_info *info)

{

  int regnum = or32_extract (param_ch, encoding, insn);

#if DEBUG

  printf ("or32_print_register: %c, %s, %x\n", param_ch, encoding, insn);

#endif  

  if (param_ch == 'A')

    //(*info->fprintf_func) (info->stream, "r%d", regnum);

    printf("r%d", regnum);

  else if (param_ch == 'B')

    //(*info->fprintf_func) (info->stream, "r%d", regnum);

    printf("r%d", regnum);

  else if (param_ch == 'D')

    //(*info->fprintf_func) (info->stream, "r%d", regnum);

    printf("r%d", regnum);

  else if (regnum < 16)

    //(*info->fprintf_func) (info->stream, "r%d", regnum);

    printf("r%d", regnum);

  else if (regnum < 32)

    //(*info->fprintf_func) (info->stream, "r%d", regnum-16);

    printf("r%d", regnum-16);

  else

    //(*info->fprintf_func) (info->stream, "X%d", regnum);

    printf("X%d", regnum);

}

/* Print immediate to INFO->STREAM. Used only by print_insn.  */

static void

or32_print_immediate (char param_ch,

                      char *encoding,

                      unsigned long insn)

                      //struct disassemble_info *info)

{

  int imm = or32_extract(param_ch, encoding, insn);

  if (letter_signed(param_ch))

    //(*info->fprintf_func) (info->stream, "0x%x", imm);

    printf("0x%x", imm);

/*    (*info->fprintf_func) (info->stream, "%d", imm); */

  else

    //(*info->fprintf_func) (info->stream, "0x%x", imm);

    printf("0x%x", imm);

}

/* Print one instruction from MEMADDR on INFO->STREAM.

   Return the size of the instruction (always 4 on or32).  */

static int

//print_insn (bfd_vma memaddr, struct disassemble_info *info)

print_insn(unsigned long insn)

{

  /* The raw instruction.  */

  unsigned char insn_ch[4];

  /* Address. Will be sign extened 27-bit.  */

  unsigned long addr;

  /* The four bytes of the instruction.  */

  //unsigned long insn;

  //find_byte_func_type find_byte_func = (find_byte_func_type) info->private_data;

  struct or32_opcode const * opcode;

  /*

  {

    int status =

      (*info->read_memory_func) (memaddr, (bfd_byte *) &insn_ch[0], 4, info);

    if (status != 0)

      {

        (*info->memory_error_func) (status, memaddr, info);

        return -1;

      }

  }

  */

  //(*find_byte_func) (&insn_ch[0], &insn);

  for (opcode = &or32_opcodes[0];

       opcode < &or32_opcodes[or32_num_opcodes];

       ++opcode)

    {

      if (or32_opcode_match (insn, opcode->encoding))

        {

          char *s;

          //(*info->fprintf_func) (info->stream, "%s ", opcode->name);

          printf("%s ", opcode->name);

          for (s = opcode->args; *s != '\0'; ++s)

            {

              switch (*s)

                {

                case '\0':

                  return 4;

                case 'r':

                  //or32_print_register (*++s, opcode->encoding, insn, info);

                  or32_print_register (*++s, opcode->encoding, insn);

                  break;

                case 'N':

                  addr = or32_extract ('N', opcode->encoding, insn) << 2;

                  int32_t int32_addr = (int32_t) addr; // Must use explicitly sized bariable here

                  //printf("int32_addr: %d ", int32_addr);

                  if (int32_addr >= 0)

                    printf("(+0x%x)", int32_addr);

                  else

                    {

                      int32_addr = (~int32_addr) + 1;

                      printf("(-0x%x)", int32_addr);

                    }

                  /* Calulate the correct address.  */

                  //addr = memaddr + EXTEND28 (addr);

                  //(*info->print_address_func)

                  //  (addr, info);

                  break;

                default:

                  if (strchr (opcode->encoding, *s))

                    //or32_print_immediate (*s, opcode->encoding, insn, info);

                    or32_print_immediate (*s, opcode->encoding, insn);

                  else

                    //(*info->fprintf_func) (info->stream, "%c", *s);

                    printf("%c", *s);

                }

            }

          return 4;

        }

    }

  /* This used to be %8x for binutils.  */

  //  (*info->fprintf_func)

  //  (info->stream, ".word 0x%08lx", insn);

  printf(".word 0x%08lx", insn);

  return 4;

}

/* Disassemble a big-endian or32 instruction.  */

/*

int

print_insn_big_or32 (bfd_vma memaddr, struct disassemble_info *info)

{

  info->private_data = find_bytes_big;

  return print_insn (memaddr, info);

}

*/

/* Disassemble a little-endian or32 instruction.  */

 /*

int

print_insn_little_or32 (bfd_vma memaddr, struct disassemble_info *info)

{

  info->private_data = find_bytes_little;

  return print_insn (memaddr, info);

}

 */

#define PRINT_ORIG_INSN_OPTION "-print-orig-insn"

static void print_or32_dis_usage(char *argv[])

{

  printf(" OpenRISC instruction decoder\n");

  printf("\n");

  printf(" Decodes an instruction passed on the command line, otherwise reads from stdin.\n");

  printf(" The option %s prints out the original instruction along with the decoded version\n similar to the objdump disassembler output, except without address information\n", PRINT_ORIG_INSN_OPTION);

  printf("\n");

  printf(" Usage:\n");

  printf("\n");

  printf(" Decode a single instruction from the command line:\n");

  printf(" \t%s 0x1500000\n", argv[0]);

  printf("\n");

  printf(" Decode a list of instructions from stdin:\n");

  printf(" \t%s < list_of_insns\n", argv[0]);

  printf("\n");

  printf(" Decode a list of instructions from stdin, and print out the original instruction as well:\n");

  printf(" \t%s -print-orig-insn < list_of_insns\n", argv[0]);

  printf("\n");

  printf(" Note: The values don't require the leading \"0x\"\n");

  printf("\n");

  return;

}

// Simple program to do disassembly like or32-objdump but on individual instructions passed to it

  // Pass the instruction in hex

int main (int argc, char *argv[])

{

  unsigned long insn;

  int print_orig_inst_option = 0; // Don't print the instruction we're passed, by default, just the decoded version

  // extract possible options we were passed

  int i;

  for(i=1;i<argc;i++)

    {

      // First check if it's an option we've been passed

      if (strncmp(argv[i],"-", 1) == 0 )

        {

          //printf("option detected at argv[%d]\n", i);

          if (strcmp(argv[i],PRINT_ORIG_INSN_OPTION) == 0 )

            {

              print_orig_inst_option = 1;

              break;

            }

          if (strncmp(argv[i],"-h",2) == 0 )

            {

              print_or32_dis_usage(argv);

              return 0;

            }

        }

    }

  int use_stdin = 0;

  if ((argc == 3 && print_orig_inst_option) || (argc == 2 && !print_orig_inst_option))

    use_stdin = 0;

  else

    use_stdin = 1;

  if (!use_stdin) // Just read the instruction passed to us on the command line and exit

    {

      int index = 1;

      if (argc > 2 )

        {

          if (i == 1) index++; // If the option was the first thing passed, the instruction is in argv[2]

        }

      insn = strtoul(argv[index], NULL, 16);

      if (print_orig_inst_option)

        printf(" %.8lx\t", insn);

      print_insn (insn);

      printf("\n");

    }

  else

    {

      char inp[10]; // Buffer is long enough to have an 8 char hex value plus its leading "0x", but that is not essential

      while(1) // Loop, reading from stdin

        {

          char c;

          c = getchar();

          //printf("%c",c);

          if (c == '\n') // End of a line - now determine the instruction we've been given

            {

              insn = strtoul(inp, NULL, 16);

              if (print_orig_inst_option)

                printf(" %.8lx\t", insn);

              print_insn (insn);

              printf("\n");

              // clear our little buffer

              for(i=0;i<10;i++)inp[i]=0;

            }

          else if (c == EOF)

            {

              break;

            }

          else

            {

              for(i=0;i<9-1;i++)inp[i]=inp[i+1];

              inp[7]=c;

            }

        }

    }

  return 0;

}