Add PDP-11 support

1 files changed, 1618 insertions, 0 deletions

diff --git a/gas/config/tc-pdp11.c b/gas/config/tc-pdp11.c
new file mode 100644
index 0000000..6935bce
--- /dev/null
+++ b/gas/config/tc-pdp11.c
@@ -0,0 +1,1618 @@
+/* tc-pdp11.c - pdp11-specific -
+   Copyright (C) 2001 Free Software Foundation, Inc.
+
+   This file is part of GAS, the GNU Assembler.
+
+   GAS 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 2, or (at your option)
+   any later version.
+
+   GAS 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 GAS; see the file COPYING.  If not, write to
+   the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+/*
+  Apparently unused functions:
+    md_convert_frag
+    md_estimate_size_before_relax
+    md_create_short_jump
+    md_create_long_jump
+*/
+
+#include "as.h"
+#include "opcode/pdp11.h"
+
+static int set_option PARAMS ((char *arg));
+static int set_cpu_model PARAMS ((char *arg));
+static int set_machine_model PARAMS ((char *arg));
+
+#define TRUE 1
+#define FALSE 0
+
+/*
+ * A representation for PDP-11 machine code.
+ */
+struct pdp11_code
+{
+  char *error;
+  int code;
+  int additional;	/* is there an additional word? */
+  int word;		/* additional word, if any */
+  struct
+  {
+    bfd_reloc_code_real_type type;
+    expressionS exp;
+    int pc_rel;
+  } reloc;
+};
+
+/*
+ * Instruction set extensions.
+ *
+ * If you change this from an array to something else, please update
+ * the "PDP-11 instruction set extensions" comment in pdp11.h.
+ */
+int pdp11_extension[PDP11_EXT_NUM];
+
+/*
+ * Assembly options.
+ */
+
+#define ASM_OPT_PIC 1
+#define ASM_OPT_NUM 2
+
+int asm_option[ASM_OPT_NUM];
+
+/* These chars start a comment anywhere in a source file (except inside
+   another comment */
+CONST char comment_chars[] = "#/";
+
+/* These chars only start a comment at the beginning of a line. */
+CONST char line_comment_chars[] = "#/";
+
+CONST char line_separator_chars[] = ";";
+
+/* Chars that can be used to separate mant from exp in floating point nums */
+CONST char EXP_CHARS[] = "eE";
+
+/* Chars that mean this number is a floating point constant */
+/* as in 0f123.456 */
+/* or    0H1.234E-12 (see exp chars above) */
+CONST char FLT_CHARS[] = "dDfFgGhH";
+
+void pseudo_even (int);
+void pseudo_bss (int);
+
+CONST pseudo_typeS md_pseudo_table[] =
+{
+  { "bss", pseudo_bss, 0 },
+  { "even", pseudo_even, 0 },
+  { 0, 0, 0 },
+};
+
+
+static void
+init_defaults ()
+{
+  static int first = 1;
+
+  if (first)
+    {
+      set_option ("all-extensions");
+      set_option ("pic");
+      first = 0;
+    }
+}
+
+static struct hash_control *insn_hash = NULL;
+
+void
+md_begin ()
+{
+  int i;
+
+  init_defaults ();
+
+  insn_hash = hash_new ();
+  if (insn_hash == NULL)
+    as_fatal ("Virtual memory exhausted");
+    
+  for (i = 0; i < pdp11_num_opcodes; i++)
+    hash_insert (insn_hash, pdp11_opcodes[i].name, (PTR)(pdp11_opcodes + i));
+  for (i = 0; i < pdp11_num_aliases; i++)
+    hash_insert (insn_hash, pdp11_aliases[i].name, (PTR)(pdp11_aliases + i));
+}
+
+void
+md_number_to_chars (con, value, nbytes)
+     char con[];
+     valueT value;
+     int nbytes;
+{
+  /* On a PDP-11, 0x1234 is stored as "\x12\x34", and
+   * 0x12345678 is stored as "\x56\x78\x12\x34". It's
+   * anyones guess what 0x123456 would be stored like.
+   */
+
+  switch (nbytes)
+    {
+    case 0:
+      break;
+    case 1:
+      con[0] =  value       & 0xff;
+      break;
+    case 2:
+      con[0] =  value       & 0xff;
+      con[1] = (value >>  8) & 0xff;
+      break;
+    case 4:
+      con[0] = (value >> 16) & 0xff;
+      con[1] = (value >> 24) & 0xff;
+      con[2] =  value       & 0xff;
+      con[3] = (value >>  8) & 0xff;
+      break;
+    default:
+      BAD_CASE (nbytes);
+    }		  
+}
+
+/* Fix up some data or instructions after we find out the value of a symbol
+   that they reference.  */
+
+int				/* Knows about order of bytes in address. */
+md_apply_fix (fixP, value)
+     fixS *fixP;
+     valueT *value;
+{
+  valueT code;
+  valueT mask;
+  char *buf;
+  int shift;
+  int size;
+
+  buf = fixP->fx_where + fixP->fx_frag->fr_literal;
+  size = fixP->fx_size;
+  code = md_chars_to_number (buf, size);
+
+  switch (fixP->fx_r_type)
+    {
+    case BFD_RELOC_16:
+    case BFD_RELOC_16_PCREL:
+      mask = 0xffff;
+      shift = 0;
+      break;
+    case BFD_RELOC_PDP11_DISP_8_PCREL:
+      mask = 0x00ff;
+      shift = 1;
+      break;
+    case BFD_RELOC_PDP11_DISP_6_PCREL:
+      mask = 0x003f;
+      shift = 1;
+      break;
+    default:
+      BAD_CASE (fixP->fx_r_type);
+    }
+
+  if (fixP->fx_addsy != NULL)
+    *value += symbol_get_bfdsym (fixP->fx_addsy)->section->vma;
+    /* *value += fixP->fx_addsy->bsym->section->vma; */
+
+  code &= ~mask;
+  code |= (*value >> shift) & mask;
+  number_to_chars_littleendian (buf, code, size);
+  return 0;
+}
+
+long
+md_chars_to_number (con, nbytes)
+     unsigned char con[];	/* Low order byte 1st. */
+     int nbytes;		/* Number of bytes in the input. */
+{
+  /* On a PDP-11, 0x1234 is stored as "\x12\x34", and
+   * 0x12345678 is stored as "\x56\x78\x12\x34". It's
+   * anyones guess what 0x123456 would be stored like.
+   */
+
+  switch (nbytes)
+    {
+    case 0:
+      return 0;
+    case 1:
+      return con[0];
+    case 2:
+      return (con[1] << BITS_PER_CHAR) | con[0];
+    case 4:
+      return
+	(((con[1] << BITS_PER_CHAR) | con[0]) << (2 * BITS_PER_CHAR)) |
+	 ((con[3] << BITS_PER_CHAR) | con[2]);
+    default:
+      BAD_CASE (nbytes);
+      return 0;
+    }		  
+}
+
+static char *
+skip_whitespace (char *str)
+{
+  while (*str == ' ' || *str == '\t')
+    str++;
+  return str;
+}
+
+static char *
+find_whitespace (char *str)
+{
+  while (*str != ' ' && *str != '\t' && *str != 0)
+    str++;
+  return str;
+}
+
+static char
+mklower (char c)
+{
+  if (isupper (c))
+    return tolower (c);
+  return c;
+}
+
+static char *
+parse_reg (char *str, struct pdp11_code *operand)
+{
+  str = skip_whitespace (str);
+  if (mklower (*str) == 'r')
+    {
+      str++;
+      switch (*str)
+	{
+	case '0': case '1': case '2': case '3':
+	case '4': case '5': case '6': case '7':
+	  operand->code = *str - '0';
+	  str++;
+	  break;
+	default:
+	  operand->error = "Bad register name";
+	  return str - 1;
+	}
+    }
+  else if (strncmp (str, "sp", 2) == 0 ||
+	   strncmp (str, "SP", 2) == 0)
+    {
+      operand->code = 6;
+      str += 2;
+    }
+  else if (strncmp (str, "pc", 2) == 0 ||
+	   strncmp (str, "PC", 2) == 0)
+    {
+      operand->code = 7;
+      str += 2;
+    }
+  else
+    {
+      operand->error = "Bad register name";
+      return str;
+    }
+
+  return str;
+}
+
+static char *
+parse_ac (char *str, struct pdp11_code *operand)
+{
+  str = skip_whitespace (str);
+  if (strncmp (str, "fr", 2) == 0 ||
+      strncmp (str, "FR", 2) == 0 ||
+      strncmp (str, "ac", 2) == 0 ||
+      strncmp (str, "AC", 2) == 0)
+    {
+      str += 2;
+      switch (*str)
+	{
+	case '0': case '1': case '2': case '3':
+	  operand->code = *str - '0';
+	  str++;
+	  break;
+	default:
+	  operand->error = "Bad register name";
+	  return str - 2;
+	}
+    }
+  else
+    {
+      operand->error = "Bad register name";
+      return str;
+    }
+
+  return str;
+}
+
+static char *
+parse_expression (char *str, struct pdp11_code *operand)
+{
+  char *save_input_line_pointer;
+  segT seg;
+
+  save_input_line_pointer = input_line_pointer;
+  input_line_pointer = str;
+  seg = expression (&operand->reloc.exp);
+  if (seg == NULL)
+    {
+      input_line_pointer = save_input_line_pointer;
+      operand->error = "Error in expression";
+      return str;
+    }
+
+  str = input_line_pointer;
+  input_line_pointer = save_input_line_pointer;
+
+  operand->reloc.pc_rel = 0;
+
+  if (operand->reloc.exp.X_op == O_constant)
+    {
+      if (*str == '.')
+	str++;
+      else
+	{
+	  /* FIXME: buffer overflow! */
+	  char buf[100];
+	  char *end;
+
+	  sprintf (buf, "%ld", operand->reloc.exp.X_add_number);
+	  operand->reloc.exp.X_add_number = strtol (buf, &end, 8);
+	}
+    }
+
+  return str;
+}
+
+static char *
+parse_op_no_deferred (char *str, struct pdp11_code *operand)
+{
+  str = skip_whitespace (str);
+
+  switch (*str)
+    {
+    case '(':				/* (rn) and (rn)+ */
+      str = parse_reg (str + 1, operand);
+      if (operand->error)
+	return str;
+      str = skip_whitespace (str);
+      if (*str != ')')
+	{
+	  operand->error = "Missing ')'";
+	  return str;
+	}
+      str++;
+      if (*str == '+')
+	{
+	  operand->code |= 020;
+	  str++;
+	}
+      else
+	{
+	  operand->code |= 010;
+	}
+      break;
+
+    case '#':				/* immediate */
+    case '$': 
+      str = parse_expression (str + 1, operand);
+      if (operand->error)
+	return str;
+      operand->additional = TRUE;
+      operand->word = operand->reloc.exp.X_add_number;
+      switch (operand->reloc.exp.X_op)
+	{
+	case O_constant:
+	  break;
+	case O_symbol:
+	case O_add:
+	case O_subtract:
+	  operand->reloc.type = BFD_RELOC_16;
+	  operand->reloc.pc_rel = 0;
+	  break;
+	default:
+	  operand->error = "Error in expression";
+	  break;
+	}
+      operand->code = 027;
+      break;
+
+    default:				/* label, d(rn), -(rn) */
+      {
+	char *old = str;
+
+	if (strncmp (str, "-(", 2) == 0)	/* -(rn) */
+	  {
+	    str = parse_reg (str + 2, operand);
+	    if (operand->error)
+	      return str;
+	    str = skip_whitespace (str);
+	    if (*str != ')')
+	      {
+		operand->error = "Missing ')'";
+		return str;
+	      }
+	    operand->code |= 040;
+	    str++;
+	    break;
+	  }
+
+	str = parse_expression (str, operand);
+	if (operand->error)
+	  return str;
+
+	str = skip_whitespace (str);
+
+	if (*str != '(')		/* label */
+	  {
+	    if (operand->reloc.exp.X_op != O_symbol)
+	      {
+		operand->error = "Label expected";
+		return old;
+	      }
+	    operand->code = 067;
+	    operand->additional = 1;
+	    operand->word = 0;
+	    operand->reloc.type = BFD_RELOC_16_PCREL;
+	    operand->reloc.pc_rel = 1;
+	    break;
+	  }
+
+	str++;				/* d(rn) */
+	str = parse_reg (str, operand);
+	if (operand->error)
+	  return str;
+
+	str = skip_whitespace (str);
+
+	if (*str != ')')
+	  {
+	    operand->error = "Missing ')'";
+	    return str;
+	  }
+
+	str++;
+	operand->additional = TRUE;
+	operand->code |= 060;
+	switch (operand->reloc.exp.X_op)
+	  {
+	  case O_symbol:
+	    operand->word = 0;
+	    operand->reloc.pc_rel = 1;
+	    break;
+	  case O_constant:
+	    if ((operand->code & 7) == 7)
+	      {
+		operand->reloc.pc_rel = 1;
+		operand->word = operand->reloc.exp.X_add_number;
+	      }
+	    else
+	      {
+		operand->word = operand->reloc.exp.X_add_number;
+	      }
+	    break;
+	  default:
+	    BAD_CASE (operand->reloc.exp.X_op);
+	  }
+	break;
+      }
+    }
+
+  return str;
+}
+
+static char *
+parse_op (char *str, struct pdp11_code *operand)
+{
+  str = skip_whitespace (str);
+
+  str = parse_reg (str, operand);
+  if (!operand->error)
+    return str;
+  operand->error = NULL;
+
+  if (*str == '@' || *str == '*')
+    {
+      str = parse_op_no_deferred (str + 1, operand);
+      if (operand->error)
+	return str;
+      operand->code |= 010;
+    }
+  else
+    str = parse_op_no_deferred (str, operand);
+
+  return str;
+}
+
+static char *
+parse_separator (char *str, int *error)
+{
+  str = skip_whitespace (str);
+  *error = (*str != ',');
+  if (!*error)
+    str++;
+  return str;
+}
+
+void
+md_assemble (instruction_string)
+     char *instruction_string;
+{
+  CONST struct pdp11_opcode *op;
+  struct pdp11_code insn, op1, op2;
+  int error;
+  int size;
+  char *err = NULL;
+  char *str;
+  char *p;
+  char c;
+
+  str = skip_whitespace (instruction_string);
+  p = find_whitespace (str);
+  if (p - str == 0)
+    {
+      as_bad ("No instruction found");
+      return;
+    }
+
+  c = *p;
+  *p = '\0';
+  op = (struct pdp11_opcode *)hash_find (insn_hash, str);
+  *p = c;
+  if (op == 0)
+    {
+#if 0
+      op1.error = NULL;
+      op1.additional = FALSE;
+      op1.reloc.type = BFD_RELOC_NONE;
+      op1.code = 0;
+      op1.word = 0;
+      str = parse_expression (str, &op1);
+      if (op1.error)
+	{
+	  as_bad (op1.error);
+	  return;
+	}
+
+      {
+	char *to = frag_more (2);
+
+	md_number_to_chars (to, op1.code, 2);
+	if (insn.reloc.type != BFD_RELOC_NONE)
+	  fix_new_exp (frag_now, to - frag_now->fr_literal, 2,
+		       &insn.reloc.exp, insn.reloc.pc_rel, insn.reloc.type);
+      }
+#else
+      as_warn ("Unknown instruction");
+#endif
+
+      return;
+    }
+
+  if (!pdp11_extension[op->extension])
+    {
+      as_warn ("Unsupported instruction set extension: %s", op->name);
+      return;
+    }
+
+  insn.error = NULL;
+  insn.code = op->opcode;
+  insn.reloc.type = BFD_RELOC_NONE;
+  op1.error = NULL;
+  op1.additional = FALSE;
+  op1.reloc.type = BFD_RELOC_NONE;
+  op2.error = NULL;
+  op2.additional = FALSE;
+  op2.reloc.type = BFD_RELOC_NONE;
+
+  str = p;
+  size = 2;
+
+  switch (op->type)
+    {
+    case PDP11_OPCODE_NO_OPS:
+      str = skip_whitespace (str);
+      if (*str == 0)
+	str = "";
+      break;
+
+    case PDP11_OPCODE_IMM3:
+    case PDP11_OPCODE_IMM6:
+    case PDP11_OPCODE_IMM8:
+      str = skip_whitespace (str);
+      if (*str == '#' || *str == '$')
+	str++;
+      str = parse_expression (str, &op1);
+      if (op1.error)
+	break;
+      switch (op->type)
+	{
+	case PDP11_OPCODE_IMM3:
+	  if (op1.code & ~7)
+	    {
+	      op1.error = "3-bit immediate out of range";
+	      break;
+	    }
+	  break;
+	case PDP11_OPCODE_IMM6:
+	  if (op1.code & ~0x3f)
+	    {
+	      op1.error = "6-bit immediate out of range";
+	      break;
+	    }
+	  break;
+	case PDP11_OPCODE_IMM8:
+	  if (op1.code & ~0xff)
+	    {
+	      op1.error = "8-bit immediate out of range";
+	      break;
+	    }
+	  break;
+	}
+      insn.code |= op1.code;
+      break;
+
+    case PDP11_OPCODE_DISPL:
+      {
+	char *new;
+	new = parse_expression (str, &op1);
+	op1.code = 0;
+	op1.reloc.pc_rel = 1;
+	op1.reloc.type = BFD_RELOC_PDP11_DISP_8_PCREL;
+	if (op1.reloc.exp.X_op != O_symbol)
+	  {
+	    op1.error = "Symbol expected";
+	    break;
+	  }
+	if (op1.code & ~0xff)
+	  {
+	    err = "8-bit displacement out of range";
+	    break;
+	  }
+	str = new;
+	insn.code |= op1.code;
+	insn.reloc = op1.reloc;
+      }
+      break;
+
+    case PDP11_OPCODE_REG:
+      str = parse_reg (str, &op1);
+      if (op1.error)
+	break;
+      insn.code |= op1.code;
+      break;
+
+    case PDP11_OPCODE_OP:
+      str = parse_op (str, &op1);
+      if (op1.error)
+	break;
+      insn.code |= op1.code;
+      if (op1.additional)
+	size += 2;
+      break;
+
+    case PDP11_OPCODE_REG_OP:
+      str = parse_reg (str, &op2);
+      if (op2.error)
+	break;
+      insn.code |= op2.code << 6;
+      str = parse_separator (str, &error);
+      if (error)
+	{
+	  op2.error = "Missing ','";
+	  break;
+	}
+      str = parse_op (str, &op1);
+      if (op1.error)
+	break;
+      insn.code |= op1.code;
+      if (op1.additional)
+	size += 2;
+      break;
+
+    case PDP11_OPCODE_REG_OP_REV:
+      str = parse_op (str, &op1);
+      if (op1.error)
+	break;
+      insn.code |= op1.code;
+      if (op1.additional)
+	size += 2;
+      str = parse_separator (str, &error);
+      if (error)
+	{
+	  op2.error = "Missing ','";
+	  break;
+	}
+      str = parse_reg (str, &op2);
+      if (op2.error)
+	break;
+      insn.code |= op2.code << 6;
+      break;
+
+    case PDP11_OPCODE_AC_OP:
+      str = parse_ac (str, &op2);
+      if (op2.error)
+	break;
+      insn.code |= op2.code << 6;
+      str = parse_separator (str, &error);
+      if (error)
+	{
+	  op1.error = "Missing ','";
+	  break;
+	}
+      str = parse_op (str, &op1);
+      if (op1.error)
+	break;
+      insn.code |= op1.code;
+      if (op1.additional)
+	size += 2;
+      break;
+
+    case PDP11_OPCODE_OP_OP:
+      str = parse_op (str, &op1);
+      if (op1.error)
+	break;
+      insn.code |= op1.code << 6;
+      if (op1.additional)
+	size += 2;
+      str = parse_separator (str, &error);
+      if (error)
+	{
+	  op2.error = "Missing ','";
+	  break;
+	}
+      str = parse_op (str, &op2);
+      if (op2.error)
+	break;
+      insn.code |= op2.code;
+      if (op2.additional)
+	size += 2;
+      break;
+
+    case PDP11_OPCODE_REG_DISPL:
+      {
+	char *new;
+	str = parse_reg (str, &op2);
+	if (op2.error)
+	  break;
+	insn.code |= op2.code << 6;
+	str = parse_separator (str, &error);
+	if (error)
+	  {
+	    op1.error = "Missing ','";
+	    break;
+	  }
+	new = parse_expression (str, &op1);
+	op1.code = 0;
+	op1.reloc.pc_rel = 1;
+	op1.reloc.type = BFD_RELOC_PDP11_DISP_6_PCREL;
+	if (op1.reloc.exp.X_op != O_symbol)
+	  {
+	    op1.error = "Symbol expected";
+	    break;
+	  }
+	if (op1.code & ~0x3f)
+	  {
+	    err = "6-bit displacement out of range";
+	    break;
+	  }
+	str = new;
+	insn.code |= op1.code;
+	insn.reloc = op1.reloc;
+      }
+      break;
+      
+    default:
+      BAD_CASE (op->type);
+    }
+
+  if (op1.error)
+    err = op1.error;
+  else if (op2.error)
+    err = op2.error;
+  else
+    {
+      str = skip_whitespace (str);
+      if (*str)
+	err = "Too many operands";
+    }
+
+  {
+    char *to = NULL;
+    
+    if (err)
+      {
+	as_bad (err);
+	return;
+      }
+
+    to = frag_more (size);
+
+    md_number_to_chars (to, insn.code, 2);
+    if (insn.reloc.type != BFD_RELOC_NONE)
+      fix_new_exp (frag_now, to - frag_now->fr_literal, 2,
+		   &insn.reloc.exp, insn.reloc.pc_rel, insn.reloc.type);
+    to += 2;
+
+    if (op1.additional)
+      {
+	md_number_to_chars (to, op1.word, 2);
+	if (op1.reloc.type != BFD_RELOC_NONE)
+	  fix_new_exp (frag_now, to - frag_now->fr_literal, 2,
+		       &op1.reloc.exp, op1.reloc.pc_rel, op1.reloc.type);
+	to += 2;
+      }
+
+    if (op2.additional)
+      {
+	md_number_to_chars (to, op2.word, 2);
+	if (op2.reloc.type != BFD_RELOC_NONE)
+	  fix_new_exp (frag_now, to - frag_now->fr_literal, 2,
+		       &op2.reloc.exp, op2.reloc.pc_rel, op2.reloc.type);
+      }
+  }
+}
+
+int
+md_estimate_size_before_relax (fragP, segment)
+     fragS *fragP ATTRIBUTE_UNUSED;
+     segT segment ATTRIBUTE_UNUSED;
+{
+  return 0;
+}
+
+void
+md_convert_frag (headers, seg, fragP)
+     bfd *headers ATTRIBUTE_UNUSED;
+     segT seg ATTRIBUTE_UNUSED;
+     fragS *fragP ATTRIBUTE_UNUSED;
+{
+}
+
+CONST int md_short_jump_size = 2;
+CONST int md_long_jump_size = 4;
+
+void
+md_create_short_jump (ptr, from_addr, to_addr, frag, to_symbol)
+     char *ptr ATTRIBUTE_UNUSED;
+     addressT from_addr ATTRIBUTE_UNUSED;
+     addressT to_addr ATTRIBUTE_UNUSED;
+     fragS *frag ATTRIBUTE_UNUSED;
+     symbolS *to_symbol ATTRIBUTE_UNUSED;
+{
+}
+
+void
+md_create_long_jump (ptr, from_addr, to_addr, frag, to_symbol)
+     char *ptr ATTRIBUTE_UNUSED;
+     addressT from_addr ATTRIBUTE_UNUSED;
+     addressT to_addr ATTRIBUTE_UNUSED;
+     fragS *frag ATTRIBUTE_UNUSED;
+     symbolS *to_symbol ATTRIBUTE_UNUSED;
+{
+}
+
+static int
+set_option (arg)
+     char *arg;
+{
+  int yes = 1;
+
+  if (strcmp (arg, "all-extensions") == 0 ||
+      strcmp (arg, "all") == 0)
+    {
+      memset (pdp11_extension, ~0, sizeof pdp11_extension);
+      pdp11_extension[PDP11_NONE] = 0;
+      return 1;
+    }
+  else if (strcmp (arg, "no-extensions") == 0)
+    {
+      memset (pdp11_extension, 0, sizeof pdp11_extension);
+      pdp11_extension[PDP11_BASIC] = 1;
+      return 1;
+    }
+
+  if (strncmp (arg, "no-", 3) == 0)
+    {
+      yes = 0;
+      arg += 3;
+    }
+
+  if (strcmp (arg, "cis") == 0)			/* commersial instructions */
+    pdp11_extension[PDP11_CIS] = yes;
+  else if (strcmp (arg, "csm") == 0)		/* call supervisor mode */
+    pdp11_extension[PDP11_CSM] = yes;
+  else if (strcmp (arg, "eis") == 0)		/* extended instruction set */
+    pdp11_extension[PDP11_EIS] = pdp11_extension[PDP11_LEIS] = yes;
+  else if (strcmp (arg, "fis") == 0 ||		/* KEV11 floating-point */
+	   strcmp (arg, "kev11") == 0 ||
+	   strcmp (arg, "kev-11") == 0)
+    pdp11_extension[PDP11_FIS] = yes;
+  else if (strcmp (arg, "fpp") == 0 ||		/* FP-11 floating-point */
+	   strcmp (arg, "fpu") == 0 ||
+	   strcmp (arg, "fp11") == 0 ||
+	   strcmp (arg, "fp-11") == 0 ||
+	   strcmp (arg, "fpj11") == 0 ||
+	   strcmp (arg, "fp-j11") == 0 ||
+	   strcmp (arg, "fpj-11") == 0)
+    pdp11_extension[PDP11_FPP] = yes;
+  else if (strcmp (arg, "limited-eis") == 0)	/* limited extended insns */
+    {
+      pdp11_extension[PDP11_LEIS] = yes;
+      if (!pdp11_extension[PDP11_LEIS])
+	pdp11_extension[PDP11_EIS] = 0;
+    }
+  else if (strcmp (arg, "mfpt") == 0)		/* move from processor type */
+    pdp11_extension[PDP11_MFPT] = yes;
+  else if (strncmp (arg, "mproc", 5) == 0 ||	/* multiprocessor insns: */
+	   strncmp (arg, "multiproc", 9) == 0 )	/* TSTSET, WRTLCK */
+    pdp11_extension[PDP11_MPROC] = yes;	
+  else if (strcmp (arg, "mxps") == 0)		/* move from/to proc status */
+    pdp11_extension[PDP11_MXPS] = yes;
+  else if (strcmp (arg, "pic") == 0)		/* position-independent code */
+    asm_option[ASM_OPT_PIC] = yes;
+  else if (strcmp (arg, "spl") == 0)		/* set priority level */
+    pdp11_extension[PDP11_SPL] = yes;
+  else if (strcmp (arg, "ucode") == 0 ||	/* microcode instructions: */
+	   strcmp (arg, "microcode") == 0)	/* LDUB, MED, XFC */
+    pdp11_extension[PDP11_UCODE] = yes;
+  else
+    return 0;
+
+  return 1;
+}
+
+static int
+set_cpu_model (arg)
+     char *arg;
+{
+  char buf[4];
+  char *model = buf;
+
+  if (arg[0] == 'k')
+    arg++;
+
+  *model++ = *arg++;
+
+  if (strchr ("abdx", model[-1]) == NULL)
+    return 0;
+
+  if (model[-1] == 'd')
+    {
+      if (arg[0] == 'f' ||
+	  arg[0] == 'j')
+	model[-1] = *arg++;
+    }
+  else if (model[-1] == 'x')
+    {
+      if (arg[0] == 't')
+	model[-1] = *arg++;
+    }
+
+  if (arg[0] == '-')
+    arg++;
+
+  if (strncmp (arg, "11", 2) != 0)
+    return 0;
+  arg += 2;
+
+  if (arg[0] == '-')
+    {
+      if (*++arg == 0)
+	return 0;
+    }
+
+  /* allow up to two revision letters */
+  if (arg[0] != 0)
+    *model++ = *arg++;
+  if (arg[0] != 0)
+    *model++ = *arg++;
+
+  *model++ = 0;
+
+  set_option ("no-extensions");
+
+  if (strncmp (buf, "a", 1) == 0)		/* KA11 (11/15/20) */
+    return 1; /* no extensions */
+
+  else if (strncmp (buf, "b", 1) == 0)		/* KB11 (11/45/50/55/70) */
+    return set_option ("eis") &&
+           set_option ("spl");
+
+  else if (strncmp (buf, "da", 2) == 0)		/* KD11-A (11/35/40) */
+    return set_option ("limited-eis");
+
+  else if (strncmp (buf, "db", 2) == 0 ||	/* KD11-B (11/05/10) */
+	   strncmp (buf, "dd", 2) == 0)		/* KD11-D (11/04) */
+    return 1; /* no extensions */
+
+  else if (strncmp (buf, "de", 2) == 0)		/* KD11-E (11/34) */
+    return set_option ("eis") &&
+           set_option ("mxps");
+
+  else if (strncmp (buf, "df", 2) == 0 ||	/* KD11-F (11/03) */
+	   strncmp (buf, "dh", 2) == 0 ||	/* KD11-H (11/03) */
+	   strncmp (buf, "dq", 2) == 0)		/* KD11-Q (11/03) */
+    return set_option ("limited-eis") &&
+           set_option ("mxps");
+
+  else if (strncmp (buf, "dk", 2) == 0)		/* KD11-K (11/60) */
+    return set_option ("eis") &&
+           set_option ("mxps") &&
+           set_option ("ucode");
+
+  else if (strncmp (buf, "dz", 2) == 0)		/* KD11-Z (11/44) */
+    return set_option ("csm") &&
+           set_option ("eis") &&
+           set_option ("mfpt") &&
+           set_option ("mxps") &&
+           set_option ("spl");
+
+  else if (strncmp (buf, "f", 1) == 0)		/* F11 (11/23/24) */
+    return set_option ("eis") &&
+           set_option ("mfpt") &&
+           set_option ("mxps");
+
+  else if (strncmp (buf, "j", 1) == 0)		/* J11 (11/53/73/83/84/93/94)*/
+    return set_option ("csm") &&
+           set_option ("eis") &&
+           set_option ("mfpt") &&
+           set_option ("multiproc") &&
+           set_option ("mxps") &&
+           set_option ("spl");
+
+  else if (strncmp (buf, "t", 1) == 0)		/* T11 (11/21) */
+    return set_option ("limited-eis") &&
+           set_option ("mxps");
+
+  else
+    return 0;
+}
+
+static int
+set_machine_model (arg)
+     char *arg;
+{
+  if (strncmp (arg, "pdp-11/", 7) != 0 &&
+      strncmp (arg, "pdp11/", 6) != 0 &&
+      strncmp (arg, "11/", 3) != 0)
+    return 0;
+
+  if (strncmp (arg, "pdp", 3) == 0)
+    arg += 3;
+  if (arg[0] == '-')
+    arg++;
+  if (strncmp (arg, "11/", 3) == 0)
+    arg += 3;
+
+  if (strcmp (arg, "03") == 0)			/* 11/03 */
+    return set_cpu_model ("kd11f");		/* KD11-F */
+
+  else if (strcmp (arg, "04") == 0)		/* 11/04 */
+    return set_cpu_model ("kd11d");		/* KD11-D */
+
+  else if (strcmp (arg, "05") == 0 ||		/* 11/05 or 11/10 */
+	   strcmp (arg, "10") == 0)
+    return set_cpu_model ("kd11b");		/* KD11-B */
+
+  else if (strcmp (arg, "15") == 0 ||		/* 11/15 or 11/20 */
+	   strcmp (arg, "20") == 0)
+    return set_cpu_model ("ka11");		/* KA11 */
+
+  else if (strcmp (arg, "21") == 0)		/* 11/21 */
+    return set_cpu_model ("t11");		/* T11 */
+
+  else if (strcmp (arg, "23") == 0 ||		/* 11/23 or 11/24 */
+	   strcmp (arg, "24") == 0)
+    return set_cpu_model ("f11");		/* F11 */
+
+  else if (strcmp (arg, "34") == 0 ||		/* 11/34 or 11/34a */
+           strcmp (arg, "34a") == 0)
+    return set_cpu_model ("kd11e");		/* KD11-E */
+
+  else if (strcmp (arg, "35") == 0 ||		/* 11/35 or 11/40 */
+	   strcmp (arg, "40") == 0)
+    return set_cpu_model ("kd11da");		/* KD11-A */
+
+  else if (strcmp (arg, "44") == 0)		/* 11/44 */
+    return set_cpu_model ("kd11dz");		/* KD11-Z */
+
+  else if (strcmp (arg, "45") == 0 ||		/* 11/45/50/55/70 */
+	   strcmp (arg, "50") == 0 ||
+	   strcmp (arg, "55") == 0 ||
+	   strcmp (arg, "70") == 0)
+    return set_cpu_model ("kb11");		/* KB11 */
+
+  else if (strcmp (arg, "60") == 0)		/* 11/60 */
+    return set_cpu_model ("kd11k");		/* KD11-K */ /* FPP? */
+
+  else if (strcmp (arg, "53") == 0 ||		/* 11/53/73/83/84/93/94 */
+	   strcmp (arg, "73") == 0 ||
+	   strcmp (arg, "83") == 0 ||
+	   strcmp (arg, "84") == 0 ||
+	   strcmp (arg, "93") == 0 ||
+	   strcmp (arg, "94") == 0)
+    return set_cpu_model ("j11") &&		/* J11 */
+           set_option ("fpp");			/* All J11 machines come */
+						/* with FPP installed. */
+  else
+    return 0;
+}
+
+CONST char *md_shortopts = "m:";
+
+struct option md_longopts[] =
+{
+#define OPTION_CPU 257
+  { "cpu", required_argument, NULL, OPTION_CPU },
+#define OPTION_MACHINE 258
+  { "machine", required_argument, NULL, OPTION_MACHINE },
+#define OPTION_PIC 259
+  { "pic", no_argument, NULL, OPTION_PIC },
+  { NULL, no_argument, NULL, 0 }
+};
+
+size_t md_longopts_size = sizeof(md_longopts);
+
+/*
+ * md_parse_option
+ *	Invocation line includes a switch not recognized by the base assembler.
+ *	See if it's a processor-specific option.
+ */
+
+int
+md_parse_option (c, arg)
+     int c;
+     char *arg;
+{
+  init_defaults ();
+
+  switch (c)
+    {
+    case 'm':
+      if (set_option (arg))
+	return 1;
+      if (set_cpu_model (arg))
+	return 1;
+      if (set_machine_model (arg))
+	return 1;
+      break;
+
+    case OPTION_CPU:
+      if (set_cpu_model (arg))
+	return 1;
+      break;
+
+    case OPTION_MACHINE:
+      if (set_machine_model (arg))
+	return 1;
+      break;
+
+    case OPTION_PIC:
+      if (set_option ("pic"))
+	return 1;
+      break;
+
+    default:
+      break;
+    }
+
+  as_bad ("unrecognized option `-%c%s'", c, arg ? arg : "");
+
+  return 0;
+}
+
+/*
+One possible way of parsing options.
+
+enum
+{
+  OPTION_CSM,
+  OPTION_CIS,
+  ...
+};
+
+struct
+{
+  CONST char *pattern;
+  int opt;
+  CONST char *description;
+} options;  
+
+static struct options extension_opts[] =
+{
+  { "Ncsm", OPTION_CSM,
+			"allow (disallow) CSM instruction" },
+  { "Ncis", OPTION_CIS,
+			"allow (disallow) commersial instruction set" },
+  { "Neis", OPTION_EIS,
+			"allow (disallow) extended instruction set" },
+  ...
+  { "all-extensions", OPTION_ALL_EXTENSIONS,
+			"allow all instruction set extensions\n\
+			(this is the default)" },
+  { "no-extensions", OPTION_NO_EXTENSIONS,
+			"disallow all instruction set extensions" },
+  { "pic", OPTION_PIC,
+			"position-independent code" },
+};
+
+static struct options cpu_opts[] =
+{
+  { "Ka_11_*", OPTION_KA11, "KA11 CPU. ..." },
+  { "Kb_11_*", OPTION_KB11, "KB11 CPU. ..." },
+  { "Kd_11_a*", OPTION_KD11A, "KD11-A CPU. ..." },
+  { "Kd_11_b*", OPTION_KD11B, "KD11-B CPU. ..." },
+  { "Kd_11_d*", OPTION_KD11D, "KD11-D CPU. ..." },
+  { "Kd_11_e*", OPTION_KD11E, "KD11-E CPU. ..." },
+  { "Kd_11_f*", OPTION_KD11F, "KD11-F CPU. ..." },
+  { "Kd_11_h*", OPTION_KD11H, "KD11-H CPU. ..." },
+  { "Kd_11_q*", OPTION_KD11Q, "KD11-Q CPU. ..." },
+  { "Kd_11_z*", OPTION_KD11Z, "KD11-Z CPU. ..." },
+  { "Df_11_*", OPTION_F11, "F11 CPU. ..." },
+  { "Dj_11_*", OPTION_J11, "J11 CPU. ..." },
+  { "Dt_11_*", OPTION_T11, "T11 CPU. ..." },
+};
+
+static struct options model_opts[] =
+{
+  { "P03", OPTION_PDP11_03, "same as ..." },
+  { "P04", OPTION_PDP11_04, "same as ..." },
+  { "P05", OPTION_PDP11_05, "same as ..." },
+  { "P10", OPTION_PDP11_10, "same as ..." },
+  { "P15", OPTION_PDP11_15, "same as ..." },
+  { "P20", OPTION_PDP11_20, "same as ..." },
+  { "P21", OPTION_PDP11_21, "same as ..." },
+  { "P24", OPTION_PDP11_24, "same as ..." },
+  { "P34", OPTION_PDP11_34, "same as ..." },
+  { "P34a", OPTION_PDP11_34A, "same as ..." },
+  { "P40", OPTION_PDP11_40, "same as ..." },
+  { "P44", OPTION_PDP11_44, "same as ..." },
+  { "P45", OPTION_PDP11_45, "same as ..." },
+  { "P50", OPTION_PDP11_50, "same as ..." },
+  { "P53", OPTION_PDP11_53, "same as ..." },
+  { "P55", OPTION_PDP11_55, "same as ..." },
+  { "P60", OPTION_PDP11_60, "same as ..." },
+  { "P70", OPTION_PDP11_70, "same as ..." },
+  { "P73", OPTION_PDP11_73, "same as ..." },
+  { "P83", OPTION_PDP11_83, "same as ..." },
+  { "P84", OPTION_PDP11_84, "same as ..." },
+  { "P93", OPTION_PDP11_93, "same as ..." },
+  { "P94", OPTION_PDP11_94, "same as ..." },
+};
+
+struct
+{
+  CONST char *title;
+  struct options *opts;
+  int num;
+} all_opts[] =
+{
+  { "PDP-11 instruction set extentions",
+    extension_opts,
+    sizeof extension_opts / sizeof extension_opts[0] },
+  { "PDP-11 CPU model options", 
+    cpu_opts,
+    sizeof cpu_opts / sizeof cpu_opts[0] },
+  { "PDP-11 machine model options", 
+    model_opts,
+    sizeof model_opts / sizeof model_opts[0] },
+};
+
+int
+parse_match (char *arg, char *pattern)
+{
+  int yes = 1;
+
+  while (*pattern)
+    {
+      switch (*pattern++)
+	{
+	case 'N':
+	  if (strncmp (arg, "no-") == 0)
+	    {
+	      yes = 0;
+	      arg += 3;
+	    }
+	  break;
+
+	case 'K':
+	  if (arg[0] == 'k')
+	    arg++;
+	  break;
+
+	case 'D':
+	  if (strncmp (arg, "kd", 2) == 0)
+	    arg +=2;
+	  break;
+
+	case 'P':
+	  if (strncmp (arg, "pdp-11/", 7) == 0)
+	    arg += 7;
+	  else if (strncmp (arg, "pdp11/", 6) == 0)
+	    arg += 6;
+	  else if (strncmp (arg, "11/", 3) == 0)
+	    arg += 3;
+	  break;
+
+	case '_':
+	  if (arg[0] == "-")
+	    {
+	      if (*++arg == 0)
+		return 0;
+	    }
+	  break;
+
+	case '*':
+	  return 1;
+
+	default:
+	  if (*arg++ != pattern[-1])
+	    return 0;
+	}
+    }
+
+  return arg[0] == 0;
+}
+
+int
+fprint_opt (stream, pattern)
+     FILE *stream;
+     CONST char *pattern;
+{
+  int n;
+
+  while (*pattern)
+    {
+      switch (*pattern++)
+	{
+	case 'N':
+	  n += fprintf (stream, "(no-)");
+	  break;
+
+	case 'K':
+	  n += fprintf (stream, "k");
+	  break;
+
+	case 'P':
+	  n += fprintf (stream "11/");
+	  break;
+
+	case 'D':
+	case '_':
+	case '*':
+	  break;
+
+	default:
+	  fputc (pattern[-1], stream);
+	  n++;
+	}
+    }
+
+  return n;
+}
+
+int
+parse_option (char *arg)
+{
+  int i, j;
+
+  for (i = 0; i < sizeof all_opts / sizeof all_opts[0]; i++)
+    {
+      for (j = 0; j < all_opts[i].num; j++)
+	{
+	  if (parse_match (arg, all_opts[i].opts[j].pattern))
+	    {
+	      set_option (all_opts[i].opts[j].opt);
+	      return 1;
+	    }
+	}
+    }
+
+  return 0;
+}
+
+static void
+fprint_space (stream, n)
+     FILE *stream;
+     int n;
+{
+  while (n--)
+    fputc (' ', stream);
+}
+
+void
+md_show_usage (stream)
+     FILE *stream;
+{
+  int i, j, n;
+
+  for (i = 0; i < sizeof all_opts / sizeof all_opts[0]; i++)
+    {
+      fprintf (stream "\n%s:\n\n", all_opts[i].title);
+
+      for (j = 0; j < all_opts[i].num; j++)
+	{
+	  fprintf (stream, "-m");
+	  n = fprintf_opt (stream, all_opts[i].opts[j].pattern);
+	  fprint_space (stream, 22 - n);
+	  fprintf (stream, "%s\n", all_opts[i].opts[j].description);
+	}
+    }
+}
+*/
+
+void
+md_show_usage (stream)
+     FILE *stream;
+{
+  fprintf (stream, "\
+\n\
+PDP-11 instruction set extentions:\n\
+\n\
+-m(no-)cis		allow (disallow) commersial instruction set\n\
+-m(no-)csm		allow (disallow) CSM instruction\n\
+-m(no-)eis		allow (disallow) full extended instruction set\n\
+-m(no-)fis		allow (disallow) KEV11 floating-point instructions\n\
+-m(no-)fpp		allow (disallow) FP-11 floating-point instructions\n\
+-m(no-)fpu		allow (disallow) FP-11 floating-point instructions\n\
+-m(no-)limited-eis	allow (disallow) limited extended instruction set\n\
+-m(no-)mfpt		allow (disallow) processor type instruction\n\
+-m(no-)multiproc	allow (disallow) multiprocessor instructions\n\
+-m(no-)mxps		allow (disallow) processor status instructions\n\
+-m(no-)spl		allow (disallow) SPL instruction\n\
+-m(no-)ucode		allow (disallow) microcode instructions\n\
+-mall-extensions	allow all instruction set extensions\n\
+			(this is the default)\n\
+-mno-extentions		disallow all instruction set extensions\n\
+-pic			generate position-indepenent code\n\
+\n\
+PDP-11 CPU model options:\n\
+\n\
+-mka11*			KA11 CPU.  base line instruction set only\n\
+-mkb11*			KB11 CPU.  enable full EIS and SPL\n\
+-mkd11a*		KD11-A CPU.  enable limited EIS\n\
+-mkd11b*		KD11-B CPU.  base line instruction set only\n\
+-mkd11d*		KD11-D CPU.  base line instruction set only\n\
+-mkd11e*		KD11-E CPU.  enable full EIS, MTPS, and MFPS\n\
+-mkd11f*		KD11-F CPU.  enable limited EIS, MTPS, and MFPS\n\
+-mkd11h*		KD11-H CPU.  enable limited EIS, MTPS, and MFPS\n\
+-mkd11q*		KD11-Q CPU.  enable limited EIS, MTPS, and MFPS\n\
+-mkd11k*		KD11-K CPU.  enable full EIS, MTPS, MFPS, LDUB, MED,\n\
+			XFC, and MFPT\n\
+-mkd11z*		KD11-Z CPU.  enable full EIS, MTPS, MFPS, MFPT, SPL,\n\
+			and CSM\n\
+-mf11*			F11 CPU.  enable full EIS, MFPS, MTPS, and MFPT\n\
+-mj11*			J11 CPU.  enable full EIS, MTPS, MFPS, MFPT, SPL,\n\
+			CSM, TSTSET, and WRTLCK\n\
+-mt11*			T11 CPU.  enable limited EIS, MTPS, and MFPS\n\
+\n\
+PDP-11 machine model options:\n\
+\n\
+-m11/03			same as -mkd11f\n\
+-m11/04			same as -mkd11d\n\
+-m11/05			same as -mkd11b\n\
+-m11/10			same as -mkd11b\n\
+-m11/15			same as -mka11\n\
+-m11/20			same as -mka11\n\
+-m11/21			same as -mt11\n\
+-m11/23			same as -mf11\n\
+-m11/24			same as -mf11\n\
+-m11/34			same as -mkd11e\n\
+-m11/34a		same as -mkd11e -mfpp\n\
+-m11/35			same as -mkd11a\n\
+-m11/40			same as -mkd11a\n\
+-m11/44			same as -mkd11z\n\
+-m11/45			same as -mkb11\n\
+-m11/50			same as -mkb11\n\
+-m11/53			same as -mj11\n\
+-m11/55			same as -mkb11\n\
+-m11/60			same as -mkd11k\n\
+-m11/70			same as -mkb11\n\
+-m11/73			same as -mj11\n\
+-m11/83			same as -mj11\n\
+-m11/84			same as -mj11\n\
+-m11/93			same as -mj11\n\
+-m11/94			same as -mj11\n\
+");
+}
+
+symbolS *
+md_undefined_symbol (name)
+     char *name ATTRIBUTE_UNUSED;
+{
+  return 0;
+}
+
+valueT
+md_section_align (segment, size)
+     segT segment ATTRIBUTE_UNUSED;
+     valueT size;
+{
+  return (size + 1) & ~1;
+}
+
+long
+md_pcrel_from (fixP)
+     fixS *fixP;
+{
+  return fixP->fx_frag->fr_address + fixP->fx_where + fixP->fx_size;
+}
+
+/* Translate internal representation of relocation info to BFD target
+   format.  */
+arelent *
+tc_gen_reloc (section, fixp)
+     asection *section ATTRIBUTE_UNUSED;
+     fixS *fixp;
+{
+  arelent *reloc;
+  bfd_reloc_code_real_type code;
+
+  reloc = (arelent *) xmalloc (sizeof (arelent));
+
+  reloc->sym_ptr_ptr = (asymbol **) xmalloc (sizeof (asymbol *));
+  *reloc->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
+  reloc->address = fixp->fx_frag->fr_address + fixp->fx_where;
+
+  /* this is taken account for in md_apply_fix() */
+  reloc->addend = -symbol_get_bfdsym (fixp->fx_addsy)->section->vma;
+
+  switch (fixp->fx_r_type)
+    {
+    case BFD_RELOC_16:
+      if (fixp->fx_pcrel)
+	code = BFD_RELOC_16_PCREL;
+      else
+	code = BFD_RELOC_16;
+      break;
+
+    case BFD_RELOC_16_PCREL:
+      code = BFD_RELOC_16_PCREL;
+      break;
+
+    default:
+      BAD_CASE (fixp->fx_r_type);
+      return NULL;
+    }
+
+  reloc->howto = bfd_reloc_type_lookup (stdoutput, code);
+
+  if (reloc->howto == NULL)
+    {
+      as_bad_where (fixp->fx_file, fixp->fx_line,
+		    "Can not represent %s relocation in this object file format",
+		    bfd_get_reloc_code_name (code));
+      return NULL;
+    }
+
+  return reloc;
+}
+
+void
+pseudo_bss (c)
+     int c ATTRIBUTE_UNUSED;
+{
+  int temp;
+
+  temp = get_absolute_expression ();
+  subseg_set (bss_section, temp);
+  demand_empty_rest_of_line ();
+}
+
+void
+pseudo_even (c)
+     int c ATTRIBUTE_UNUSED;
+{
+  int alignment = 1; /* 2^1 */
+  frag_align (alignment, 0, 1);
+  record_alignment (now_seg, alignment);
+}
+
+/* end of tc-pdp11.c */