/* Disassemble AVR instructions.
  Copyright (C) 1999-2024 Free Software Foundation, Inc.

  Contributed by Denis Chertykov <[email protected]>

  This file is part of libopcodes.

  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.  */

#include "sysdep.h"
#include <assert.h>
#include "disassemble.h"
#include "opintl.h"
#include "libiberty.h"
#include <stdint.h>

struct avr_opcodes_s
{
 char *name;
 char *constraints;
 char *opcode;
 int insn_size;                /* In words.  */
 int isa;
 unsigned int bin_opcode;
};

#define AVR_INSN(NAME, CONSTR, OPCODE, SIZE, ISA, BIN) \
{#NAME, CONSTR, OPCODE, SIZE, ISA, BIN},

const struct avr_opcodes_s avr_opcodes[] =
{
 #include "opcode/avr.h"
 {NULL, NULL, NULL, 0, 0, 0}
};

static const char * comment_start = "0x";

static int
avr_operand (unsigned int        insn,
            unsigned int        insn2,
            unsigned int        pc,
            int                 constraint,
            char *              opcode_str,
            char *              buf,
            char *              comment,
            enum disassembler_style *  style,
            int                 regs,
            int *               sym,
            bfd_vma *           sym_addr,
            disassemble_info *  info)
{
 int ok = 1;
 *sym = 0;

 switch (constraint)
   {
     /* Any register operand.  */
   case 'r':
     if (regs)
       insn = (insn & 0xf) | ((insn & 0x0200) >> 5); /* Source register.  */
     else
       insn = (insn & 0x01f0) >> 4; /* Destination register.  */

     sprintf (buf, "r%d", insn);
     *style = dis_style_register;
     break;

   case 'd':
     if (regs)
       sprintf (buf, "r%d", 16 + (insn & 0xf));
     else
       sprintf (buf, "r%d", 16 + ((insn & 0xf0) >> 4));
     *style = dis_style_register;
     break;

   case 'w':
     sprintf (buf, "r%d", 24 + ((insn & 0x30) >> 3));
     *style = dis_style_register;
     break;

   case 'a':
     if (regs)
       sprintf (buf, "r%d", 16 + (insn & 7));
     else
       sprintf (buf, "r%d", 16 + ((insn >> 4) & 7));
     *style = dis_style_register;
     break;

   case 'v':
     if (regs)
       sprintf (buf, "r%d", (insn & 0xf) * 2);
     else
       sprintf (buf, "r%d", ((insn & 0xf0) >> 3));
     *style = dis_style_register;
     break;

   case 'e':
     {
       char *xyz;

       switch (insn & 0x100f)
         {
           case 0x0000: xyz = "Z";  break;
           case 0x1001: xyz = "Z+"; break;
           case 0x1002: xyz = "-Z"; break;
           case 0x0008: xyz = "Y";  break;
           case 0x1009: xyz = "Y+"; break;
           case 0x100a: xyz = "-Y"; break;
           case 0x100c: xyz = "X";  break;
           case 0x100d: xyz = "X+"; break;
           case 0x100e: xyz = "-X"; break;
           default: xyz = "??"; ok = 0;
         }
       strcpy (buf, xyz);

       if (AVR_UNDEF_P (insn))
         sprintf (comment, _("undefined"));
     }
     *style = dis_style_register;
     break;

   case 'z':
     *buf++ = 'Z';

     /* Check for post-increment. */
     char *s;
     for (s = opcode_str; *s; ++s)
       {
         if (*s == '+')
           {
             if (insn & (1 << (15 - (s - opcode_str))))
               *buf++ = '+';
             break;
           }
       }

     *buf = '\0';
     if (AVR_UNDEF_P (insn))
       sprintf (comment, _("undefined"));
     *style = dis_style_register;
     break;

   case 'b':
     {
       unsigned int x;

       x = (insn & 7);
       x |= (insn >> 7) & (3 << 3);
       x |= (insn >> 8) & (1 << 5);

       if (insn & 0x8)
         *buf++ = 'Y';
       else
         *buf++ = 'Z';
       sprintf (buf, "+%d", x);
       sprintf (comment, "0x%02x", x);
       *style = dis_style_register;
     }
     break;

   case 'h':
     *sym = 1;
     *sym_addr = ((((insn & 1) | ((insn & 0x1f0) >> 3)) << 16) | insn2) * 2;
     /* See PR binutils/2454.  Ideally we would like to display the hex
        value of the address only once, but this would mean recoding
        objdump_print_address() which would affect many targets.  */
     sprintf (buf, "%#lx", (unsigned long) *sym_addr);
     strcpy (comment, comment_start);
     info->insn_info_valid = 1;
     info->insn_type = dis_jsr;
     info->target = *sym_addr;
     *style = dis_style_address;
     break;

   case 'L':
     {
       int rel_addr = (((insn & 0xfff) ^ 0x800) - 0x800) * 2;
       sprintf (buf, ".%+-8d", rel_addr);
       *sym = 1;
       *sym_addr = pc + 2 + rel_addr;
       strcpy (comment, comment_start);
       info->insn_info_valid = 1;
       info->insn_type = dis_branch;
       info->target = *sym_addr;
       *style = dis_style_address_offset;
     }
     break;

   case 'l':
     {
       int rel_addr = ((((insn >> 3) & 0x7f) ^ 0x40) - 0x40) * 2;

       sprintf (buf, ".%+-8d", rel_addr);
       *sym = 1;
       *sym_addr = pc + 2 + rel_addr;
       strcpy (comment, comment_start);
       info->insn_info_valid = 1;
       info->insn_type = dis_condbranch;
       info->target = *sym_addr;
       *style = dis_style_address_offset;
     }
     break;

   case 'i':
     {
       unsigned int val = insn2 | 0x800000;
       *sym = 1;
       *sym_addr = val;
       sprintf (buf, "0x%04X", insn2);
       strcpy (comment, comment_start);
       *style = dis_style_immediate;
     }
     break;

   case 'j':
     {
       unsigned int val = ((insn & 0xf) | ((insn & 0x600) >> 5)
                                        | ((insn & 0x100) >> 2));
       if ((insn & 0x100) == 0)
         val |= 0x80;
       *sym = 1;
       *sym_addr = val | 0x800000;
       sprintf (buf, "0x%02x", val);
       strcpy (comment, comment_start);
       *style = dis_style_immediate;
     }
     break;

   case 'M':
     sprintf (buf, "0x%02X", ((insn & 0xf00) >> 4) | (insn & 0xf));
     sprintf (comment, "%d", ((insn & 0xf00) >> 4) | (insn & 0xf));
     *style = dis_style_immediate;
     break;

   case 'n':
     sprintf (buf, "??");
     /* xgettext:c-format */
     opcodes_error_handler (_("internal disassembler error"));
     ok = 0;
     *style = dis_style_immediate;
     break;

   case 'K':
     {
       unsigned int x;

       x = (insn & 0xf) | ((insn >> 2) & 0x30);
       sprintf (buf, "0x%02x", x);
       sprintf (comment, "%d", x);
       *style = dis_style_immediate;
     }
     break;

   case 's':
     sprintf (buf, "%d", insn & 7);
     *style = dis_style_immediate;
     break;

   case 'S':
     sprintf (buf, "%d", (insn >> 4) & 7);
     *style = dis_style_immediate;
     break;

   case 'P':
     {
       unsigned int x;

       x = (insn & 0xf);
       x |= (insn >> 5) & 0x30;
       sprintf (buf, "0x%02x", x);
       sprintf (comment, "%d", x);
       *style = dis_style_address;
     }
     break;

   case 'p':
     {
       unsigned int x;

       x = (insn >> 3) & 0x1f;
       sprintf (buf, "0x%02x", x);
       sprintf (comment, "%d", x);
       *style = dis_style_address;
     }
     break;

   case 'E':
     sprintf (buf, "%d", (insn >> 4) & 15);
     *style = dis_style_immediate;
     break;

   case '?':
     *buf = '\0';
     break;

   default:
     sprintf (buf, "??");
     /* xgettext:c-format */
     opcodes_error_handler (_("unknown constraint `%c'"), constraint);
     ok = 0;
   }

   return ok;
}

/* Read the opcode from ADDR.  Return 0 in success and save opcode
  in *INSN, otherwise, return -1.  */

static int
avrdis_opcode (bfd_vma addr, disassemble_info *info, uint16_t *insn)
{
 bfd_byte buffer[2];
 int status;

 status = info->read_memory_func (addr, buffer, 2, info);

 if (status == 0)
   {
     *insn = bfd_getl16 (buffer);
     return 0;
   }

 info->memory_error_func (status, addr, info);
 return -1;
}


int
print_insn_avr (bfd_vma addr, disassemble_info *info)
{
 uint16_t insn, insn2;
 const struct avr_opcodes_s *opcode;
 static unsigned int *maskptr;
 void *stream = info->stream;
 fprintf_styled_ftype prin = info->fprintf_styled_func;
 static unsigned int *avr_bin_masks;
 static int initialized;
 int cmd_len = 2;
 int ok = 0;
 char op1[20], op2[20], comment1[40], comment2[40];
 enum disassembler_style style_op1, style_op2;
 int sym_op1 = 0, sym_op2 = 0;
 bfd_vma sym_addr1, sym_addr2;

 /* Clear instruction information field.  */
 info->insn_info_valid = 0;
 info->branch_delay_insns = 0;
 info->data_size = 0;
 info->insn_type = dis_noninsn;
 info->target = 0;
 info->target2 = 0;

 if (!initialized)
   {
     unsigned int nopcodes;

     /* PR 4045: Try to avoid duplicating the 0x prefix that
        objdump_print_addr() will put on addresses when there
        is no symbol table available.  */
     if (info->symtab_size == 0)
       comment_start = " ";

     nopcodes = sizeof (avr_opcodes) / sizeof (struct avr_opcodes_s);

     avr_bin_masks = xmalloc (nopcodes * sizeof (unsigned int));

     for (opcode = avr_opcodes, maskptr = avr_bin_masks;
          opcode->name;
          opcode++, maskptr++)
       {
         char * s;
         unsigned int bin = 0;
         unsigned int mask = 0;

         for (s = opcode->opcode; *s; ++s)
           {
             bin <<= 1;
             mask <<= 1;
             bin |= (*s == '1');
             mask |= (*s == '1' || *s == '0');
           }
         assert (s - opcode->opcode == 16);
         assert (opcode->bin_opcode == bin);
         *maskptr = mask;
       }

     initialized = 1;
   }

 if (avrdis_opcode (addr, info, &insn)  != 0)
   return -1;

 for (opcode = avr_opcodes, maskptr = avr_bin_masks;
      opcode->name;
      opcode++, maskptr++)
   {
     if ((opcode->isa == AVR_ISA_TINY) && (info->mach != bfd_mach_avrtiny))
       continue;
     if ((insn & *maskptr) == opcode->bin_opcode)
       break;
   }

 /* Special case: disassemble `ldd r,b+0' as `ld r,b', and
    `std b+0,r' as `st b,r' (next entry in the table).  */

 if (AVR_DISP0_P (insn))
   opcode++;

 op1[0] = 0;
 op2[0] = 0;
 comment1[0] = 0;
 comment2[0] = 0;
 style_op1 = dis_style_text;
 style_op2 = dis_style_text;

 if (opcode->name)
   {
     char *constraints = opcode->constraints;
     char *opcode_str = opcode->opcode;

     insn2 = 0;
     ok = 1;

     if (opcode->insn_size > 1)
       {
         if (avrdis_opcode (addr + 2, info, &insn2) != 0)
           return -1;
         cmd_len = 4;
       }

     if (*constraints && *constraints != '?')
       {
         int regs = REGISTER_P (*constraints);

         ok = avr_operand (insn, insn2, addr, *constraints, opcode_str, op1,
                           comment1, &style_op1, 0, &sym_op1, &sym_addr1,
                           info);

         if (ok && *(++constraints) == ',')
           ok = avr_operand (insn, insn2, addr, *(++constraints), opcode_str,
                             op2, *comment1 ? comment2 : comment1,
                             &style_op2, regs, &sym_op2, &sym_addr2,
                             info);
       }
   }

 if (!ok)
   {
     /* Unknown opcode, or invalid combination of operands.  */
     sprintf (op1, "0x%04x", insn);
     op2[0] = 0;
     sprintf (comment1, "????");
     comment2[0] = 0;
   }

 (*prin) (stream, ok ? dis_style_mnemonic : dis_style_assembler_directive,
          "%s", ok ? opcode->name : ".word");

 if (*op1)
   (*prin) (stream, style_op1, "\t%s", op1);

 if (*op2)
   {
     (*prin) (stream, dis_style_text, ", ");
     (*prin) (stream, style_op2, "%s", op2);
   }

 if (*comment1)
   (*prin) (stream, dis_style_comment_start, "\t; %s", comment1);

 if (sym_op1)
   info->print_address_func (sym_addr1, info);

 if (*comment2)
   (*prin) (stream, dis_style_comment_start, " %s", comment2);

 if (sym_op2)
   info->print_address_func (sym_addr2, info);

 return cmd_len;
}