/* disassemble sparc instructions for objdump
   Copyright (C) 1986, 1987, 1989, 1991 Free Software Foundation, Inc.


This file is part of the binutils.

The binutils are 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, or (at your option)
any later version.

The binutils are distributed in the hope that they 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 the binutils; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */

/* $Id$ */

#include "bfd.h"
#include "sysdep.h"
#include <stdio.h>
#include "sparc-opcode.h"

extern int fputs();
extern int print_address();

static  char *reg_names[] =
 { "g0", "g1", "g2", "g3", "g4", "g5", "g6", "g7",	
  "o0", "o1", "o2", "o3", "o4", "o5", "sp", "o7",	
  "l0", "l1", "l2", "l3", "l4", "l5", "l6", "l7",	
  "i0", "i1", "i2", "i3", "i4", "i5", "fp", "i7",	
  "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7",	
  "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15",	
  "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23",
  "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31",
  "y", "psr", "wim", "tbr", "pc", "npc", "fpsr", "cpsr" };

#define	freg_names	(&reg_names[4 * 8])

union sparc_insn
  {
    unsigned long int code;
    struct
      {
	unsigned int _OP:2;
#define	op	ldst._OP
	unsigned int _RD:5;
#define	rd	ldst._RD
	unsigned int op3:6;
	unsigned int _RS1:5;
#define	rs1	ldst._RS1
	unsigned int i:1;
	unsigned int _ASI:8;
#define	asi	ldst._ASI
	unsigned int _RS2:5;
#define	rs2	ldst._RS2
#define	shcnt	rs2
      } ldst;
    struct
      {
	unsigned int _OP:2, _RD:5, op3:6, _RS1:5, i:1;
	unsigned int IMM13:13;
#define	imm13	IMM13.IMM13
      } IMM13;
    struct
      {
	unsigned int _OP:2;
	unsigned int a:1;
	unsigned int cond:4;
	unsigned int op2:3;
	unsigned int DISP22:22;
#define	disp22	branch.DISP22
      } branch;
#ifndef NO_V9
    struct
      {
	unsigned int _OP:2, _RD:5, op3:6, _RS1:5;
	unsigned int DISP14:14;
#define	disp14	DISP14.DISP14
      } DISP14;
    struct
      {
	unsigned int _OP:2;
	unsigned int a:1;
	unsigned int cond:4;
	unsigned int op2:3;
	unsigned int p:1;
	unsigned int DISP21:21;
#define	disp21	branch2.DISP21
      } branch2;
#endif /* NO_V9 */

#define	imm22	disp22
    struct
      {
	unsigned int _OP:2;
	unsigned int _DISP30:30;
#define	disp30	call._DISP30
      } call;
  };

/* Nonzero if INSN is the opcode for a delayed branch.  */
static int
is_delayed_branch (insn)
     union sparc_insn insn;
{
  unsigned int i;

  for (i = 0; i < NUMOPCODES; ++i)
    {
      const struct sparc_opcode *opcode = &sparc_opcodes[i];
      if ((opcode->match & insn.code) == opcode->match
	  && (opcode->lose & insn.code) == 0
	  && (opcode->flags&F_DELAYED))
	return 1;
    }
  return 0;
}

static int opcodes_sorted = 0;

/* Print one instruction from MEMADDR on STREAM.  */
int
print_insn_sparc (memaddr, buffer,  stream)
     bfd_vma memaddr;
    bfd_byte  *buffer;
     FILE *stream;
     
{
  union sparc_insn insn;

  register unsigned int i;

  if (!opcodes_sorted)
    {
      static int compare_opcodes ();
      qsort ((char *) sparc_opcodes, NUMOPCODES,
	     sizeof (sparc_opcodes[0]), compare_opcodes);
      opcodes_sorted = 1;
    }

memcpy(&insn,buffer, sizeof (insn));

  for (i = 0; i < NUMOPCODES; ++i)
    {
      const struct sparc_opcode *opcode = &sparc_opcodes[i];
      if ((opcode->match & insn.code) == opcode->match
	  && (opcode->lose & insn.code) == 0)
	{
	  /* Nonzero means that we have found an instruction which has
	     the effect of adding or or'ing the imm13 field to rs1.  */
	  int imm_added_to_rs1 = 0;

	  /* Nonzero means that we have found a plus sign in the args
	     field of the opcode table.  */
	  int found_plus = 0;
	  
	  /* Do we have an 'or' instruction where rs1 is the same
	     as rsd, and which has the i bit set?  */
	  if (opcode->match == 0x80102000
	      && insn.rs1 == insn.rd)
	    imm_added_to_rs1 = 1;

	  if (index (opcode->args, 'S') != 0)
	    /* Reject the special case for `set'.
	       The real `sethi' will match.  */
	    continue;
	  if (insn.rs1 != insn.rd
	      && index (opcode->args, 'r') != 0)
	      /* Can't do simple format if source and dest are different.  */
	      continue;

	  fputs (opcode->name, stream);

	  {
	    register const char *s;

	    if (opcode->args[0] != ',')
	      fputs (" ", stream);
	    for (s = opcode->args; *s != '\0'; ++s) {
		while (*s == ',') {
			fputs (",", stream);
			++s;

			switch (*s) {
			case 'a':
				fputs ("a", stream);
				++s;
				continue;
#ifndef NO_V9
			case 'N':
				fputs("pn", stream);
				++s;
				continue;

			case 'T':
				fputs("pt", stream);
				++s;
				continue;
#endif /* NO_V9 */

			default:
				break;
			} /* switch on arg */
		} /* while there are comma started args */

		fputs (" ", stream);
			
		switch (*s)
		  {
		  case '+':
		    found_plus = 1;

		    /* note fall-through */
		  default:
		    fprintf (stream, "%c", *s);
		    break;

		  case '#':
		    fputs ("0", stream);
		    break;

#define	reg(n)	fprintf (stream, "%%%s", reg_names[n])
		  case '1':
		  case 'r':
		    reg (insn.rs1);
		    break;

		  case '2':
		    reg (insn.rs2);
		    break;

		  case 'd':
		    reg (insn.rd);
		    break;
#undef	reg

#define	freg(n)	fprintf (stream, "%%%s", freg_names[n])
		  case 'e':
		    freg (insn.rs1);
		    break;

		  case 'f':
		    freg (insn.rs2);
		    break;

		  case 'g':
		    freg (insn.rd);
		    break;
#undef	freg

#define	creg(n)	fprintf (stream, "%%c%u", (unsigned int) (n))
		  case 'b':
		    creg (insn.rs1);
		    break;

		  case 'c':
		    creg (insn.rs2);
		    break;

		  case 'D':
		    creg (insn.rd);
		    break;
#undef	creg

		  case 'h':
		    fprintf (stream, "%%hi(%#x)",
				      (unsigned int) insn.imm22 << 10);
		    break;

		  case 'i':
		    {
		      /* We cannot trust the compiler to sign-extend
			 when extracting the bitfield, hence the shifts.  */
		      int imm = ((int) insn.imm13 << 19) >> 19;

		      /* Check to see whether we have a 1+i, and take
			 note of that fact.

			 Note: because of the way we sort the table,
			 we will be matching 1+i rather than i+1,
			 so it is OK to assume that i is after +,
			 not before it.  */
		      if (found_plus)
			imm_added_to_rs1 = 1;
		      
		      if (imm <= 9)
			fprintf (stream, "%d", imm);
		      else
			fprintf (stream, "%#x", (unsigned) imm);
		    }
		    break;

#ifndef NO_V9
		  case 'k':
		    print_address ((bfd_vma)
				   (memaddr
				    + (((int) insn.disp14 << 18) >> 18) * 4),
				   stream);
		    break;

		  case 'K':
		    print_address ((bfd_vma)
				   (memaddr
				    + (((int) insn.disp21 << 11) >> 11) * 4),
				   stream);
		    break;

	    case 'Y':
		    fputs ("%amr", stream);
		    break;

#endif /* NO_V9 */

	    case 'M':
		    fprintf(stream, "%%asr%d", insn.rs1);
		    break;
		    
	    case 'm':
		    fprintf(stream, "%%asr%d", insn.rd);
		    break;
		    
	    case 'L':
		    print_address ((bfd_vma) memaddr + insn.disp30 * 4,
				   stream);
		    break;

		  case 'l':
		    if ((insn.code >> 22) == 0)
		      /* Special case for `unimp'.  Don't try to turn
			 it's operand into a function offset.  */
		      fprintf (stream, "%#x",
					(unsigned) (((int) insn.disp22 << 10) >> 10));
		    else
		      /* We cannot trust the compiler to sign-extend
			 when extracting the bitfield, hence the shifts.  */
		      print_address ((bfd_vma)
				     (memaddr
				      + (((int) insn.disp22 << 10) >> 10) * 4),
				     stream);
		    break;

		  case 'A':
		    fprintf (stream, "(%d)", (int) insn.asi);
		    break;

		  case 'C':
		    fputs ("%csr", stream);
		    break;

		  case 'F':
		    fputs ("%fsr", stream);
		    break;

		  case 'p':
		    fputs ("%psr", stream);
		    break;

		  case 'q':
		    fputs ("%fq", stream);
		    break;

		  case 'Q':
		    fputs ("%cq", stream);
		    break;

		  case 't':
		    fputs ("%tbr", stream);
		    break;

		  case 'w':
		    fputs ("%wim", stream);
		    break;

		  case 'y':
		    fputs ("%y", stream);
		    break;
		  }
	      }
	  }

	  /* If we are adding or or'ing something to rs1, then
	     check to see whether the previous instruction was
	     a sethi to the same register as in the sethi.
	     If so, attempt to print the result of the add or
	     or (in this context add and or do the same thing)
	     and its symbolic value.  */
	  if (imm_added_to_rs1)
	    {
	      union sparc_insn prev_insn;
	      int errcode;

	      memcpy(&prev_insn, buffer -4,  sizeof (prev_insn));

	      if (errcode == 0)
		{
		  /* If it is a delayed branch, we need to look at the
		     instruction before the delayed branch.  This handles
		     sequences such as

		     sethi %o1, %hi(_foo), %o1
		     call _printf
		     or %o1, %lo(_foo), %o1
		     */

		  if (is_delayed_branch (prev_insn))
		    memcpy(&prev_insn, buffer - 8, sizeof(prev_insn));

		}

	      /* If there was a problem reading memory, then assume
		 the previous instruction was not sethi.  */
	      if (errcode == 0)
		{
		  /* Is it sethi to the same register?  */
		  if ((prev_insn.code & 0xc1c00000) == 0x01000000
		      && prev_insn.rd == insn.rs1)
		    {
		      fprintf (stream, "\t! ");
		      /* We cannot trust the compiler to sign-extend
			 when extracting the bitfield, hence the shifts.  */
		      print_address (((int) prev_insn.imm22 << 10)
				     | (insn.imm13 << 19) >> 19, stream);
		    }
		}
	    }

	  return sizeof (insn);
	}
    }

  fprintf (stream, "%#8x", insn.code);
  return sizeof (insn);
}


/* Compare opcodes A and B.  */

static int
compare_opcodes (a, b)
     char *a, *b;
{
  struct sparc_opcode *op0 = (struct sparc_opcode *) a;
  struct sparc_opcode *op1 = (struct sparc_opcode *) b;
  unsigned long int match0 = op0->match, match1 = op1->match;
  unsigned long int lose0 = op0->lose, lose1 = op1->lose;
  register unsigned int i;

  /* If a bit is set in both match and lose, there is something
     wrong with the opcode table.  */
  if (match0 & lose0)
    {
      fprintf (stderr, "Internal error:  bad sparc-opcode.h: \"%s\", %#.8lx, %#.8lx\n",
	       op0->name, match0, lose0);
      op0->lose &= ~op0->match;
      lose0 = op0->lose;
    }

  if (match1 & lose1)
    {
      fprintf (stderr, "Internal error: bad sparc-opcode.h: \"%s\", %#.8lx, %#.8lx\n",
	       op1->name, match1, lose1);
      op1->lose &= ~op1->match;
      lose1 = op1->lose;
    }

  /* Because the bits that are variable in one opcode are constant in
     another, it is important to order the opcodes in the right order.  */
  for (i = 0; i < 32; ++i)
    {
      unsigned long int x = 1 << i;
      int x0 = (match0 & x) != 0;
      int x1 = (match1 & x) != 0;

      if (x0 != x1)
	return x1 - x0;
    }

  for (i = 0; i < 32; ++i)
    {
      unsigned long int x = 1 << i;
      int x0 = (lose0 & x) != 0;
      int x1 = (lose1 & x) != 0;

      if (x0 != x1)
	return x1 - x0;
    }

  /* They are functionally equal.  So as long as the opcode table is
     valid, we can put whichever one first we want, on aesthetic grounds.  */
  {
    int length_diff = strlen (op0->args) - strlen (op1->args);
    if (length_diff != 0)
      /* Put the one with fewer arguments first.  */
      return length_diff;
  }

  /* Put 1+i before i+1.  */
  {
    char *p0 = (char *) index(op0->args, '+');
    char *p1 = (char *) index(op1->args, '+');

    if (p0 && p1)
      {
	/* There is a plus in both operands.  Note that a plus
	   sign cannot be the first character in args,
	   so the following [-1]'s are valid.  */
	if (p0[-1] == 'i' && p1[1] == 'i')
	  /* op0 is i+1 and op1 is 1+i, so op1 goes first.  */
	  return 1;
	if (p0[1] == 'i' && p1[-1] == 'i')
	  /* op0 is 1+i and op1 is i+1, so op0 goes first.  */
	  return -1;
      }
  }

  /* They are, as far as we can tell, identical.
     Since qsort may have rearranged the table partially, there is
     no way to tell which one was first in the opcode table as
     written, so just say there are equal.  */
  return 0;
}
