Initial creation of sourceware repository

[thirdparty/binutils-gdb.git] / gdb / valops.c

/* Perform non-arithmetic operations on values, for GDB.
   Copyright 1986, 87, 89, 91, 92, 93, 94, 95, 96, 97, 1998
   Free Software Foundation, Inc.

This file is part of GDB.

This program 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 of the License, or
(at your option) any later version.

This program 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include "defs.h"
#include "symtab.h"
#include "gdbtypes.h"
#include "value.h"
#include "frame.h"
#include "inferior.h"
#include "gdbcore.h"
#include "target.h"
#include "demangle.h"
#include "language.h"
#include "gdbcmd.h"

#include <errno.h>
#include "gdb_string.h"

/* Default to coercing float to double in function calls only when there is
   no prototype.  Otherwise on targets where the debug information is incorrect
   for either the prototype or non-prototype case, we can force it by defining
   COERCE_FLOAT_TO_DOUBLE in the target configuration file. */

#ifndef COERCE_FLOAT_TO_DOUBLE
#define COERCE_FLOAT_TO_DOUBLE (param_type == NULL)
#endif

/* Flag indicating HP compilers were used; needed to correctly handle some
   value operations with HP aCC code/runtime. */
extern int hp_som_som_object_present;


/* Local functions.  */

static int typecmp PARAMS ((int staticp, struct type *t1[], value_ptr t2[]));

#ifdef CALL_DUMMY
static CORE_ADDR find_function_addr PARAMS ((value_ptr, struct type **));
static value_ptr value_arg_coerce PARAMS ((value_ptr, struct type *, int));
#endif


#ifndef PUSH_ARGUMENTS
static CORE_ADDR value_push PARAMS ((CORE_ADDR, value_ptr));
#endif

static value_ptr search_struct_field PARAMS ((char *, value_ptr, int,
                                              struct type *, int));

static value_ptr search_struct_field_aux PARAMS ((char *, value_ptr, int,
                                                  struct type *, int, int *, char *,
                                                  struct type **));

static value_ptr search_struct_method PARAMS ((char *, value_ptr *,
                                               value_ptr *,
                                               int, int *, struct type *));

static int check_field_in PARAMS ((struct type *, const char *));

static CORE_ADDR allocate_space_in_inferior PARAMS ((int));

static value_ptr cast_into_complex PARAMS ((struct type *, value_ptr));

void _initialize_valops PARAMS ((void));

#define VALUE_SUBSTRING_START(VAL) VALUE_FRAME(VAL)

/* Flag for whether we want to abandon failed expression evals by default.  */

#if 0
static int auto_abandon = 0;
#endif

int overload_resolution = 0;


\f
/* Find the address of function name NAME in the inferior.  */

value_ptr
find_function_in_inferior (name)
     char *name;
{
  register struct symbol *sym;
  sym = lookup_symbol (name, 0, VAR_NAMESPACE, 0, NULL);
  if (sym != NULL)
    {
      if (SYMBOL_CLASS (sym) != LOC_BLOCK)
        {
          error ("\"%s\" exists in this program but is not a function.",
                 name);
        }
      return value_of_variable (sym, NULL);
    }
  else
    {
      struct minimal_symbol *msymbol = lookup_minimal_symbol(name, NULL, NULL);
      if (msymbol != NULL)
        {
          struct type *type;
          LONGEST maddr;
          type = lookup_pointer_type (builtin_type_char);
          type = lookup_function_type (type);
          type = lookup_pointer_type (type);
          maddr = (LONGEST) SYMBOL_VALUE_ADDRESS (msymbol);
          return value_from_longest (type, maddr);
        }
      else
        {
          if (!target_has_execution)
            error ("evaluation of this expression requires the target program to be active");
          else
            error ("evaluation of this expression requires the program to have a function \"%s\".", name);
        }
    }
}

/* Allocate NBYTES of space in the inferior using the inferior's malloc
   and return a value that is a pointer to the allocated space. */

value_ptr
value_allocate_space_in_inferior (len)
     int len;
{
  value_ptr blocklen;
  register value_ptr val = find_function_in_inferior ("malloc");

  blocklen = value_from_longest (builtin_type_int, (LONGEST) len);
  val = call_function_by_hand (val, 1, &blocklen);
  if (value_logical_not (val))
    {
      if (!target_has_execution)
        error ("No memory available to program now: you need to start the target first");
      else 
        error ("No memory available to program: call to malloc failed");
    }
  return val;
}

static CORE_ADDR
allocate_space_in_inferior (len)
     int len;
{
  return value_as_long (value_allocate_space_in_inferior (len));
}

/* Cast value ARG2 to type TYPE and return as a value.
   More general than a C cast: accepts any two types of the same length,
   and if ARG2 is an lvalue it can be cast into anything at all.  */
/* In C++, casts may change pointer or object representations.  */

value_ptr
value_cast (type, arg2)
     struct type *type;
     register value_ptr arg2;
{
  register enum type_code code1;
  register enum type_code code2;
  register int scalar;
  struct type *type2;

  int convert_to_boolean = 0;
  
  if (VALUE_TYPE (arg2) == type)
    return arg2;

  CHECK_TYPEDEF (type);
  code1 = TYPE_CODE (type);
  COERCE_REF(arg2);
  type2 = check_typedef (VALUE_TYPE (arg2));

  /* A cast to an undetermined-length array_type, such as (TYPE [])OBJECT,
     is treated like a cast to (TYPE [N])OBJECT,
     where N is sizeof(OBJECT)/sizeof(TYPE). */
  if (code1 == TYPE_CODE_ARRAY)
    {
      struct type *element_type = TYPE_TARGET_TYPE (type);
      unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
      if (element_length > 0
          && TYPE_ARRAY_UPPER_BOUND_TYPE (type) == BOUND_CANNOT_BE_DETERMINED)
        {
          struct type *range_type = TYPE_INDEX_TYPE (type);
          int val_length = TYPE_LENGTH (type2);
          LONGEST low_bound, high_bound, new_length;
          if (get_discrete_bounds (range_type, &low_bound, &high_bound) < 0)
            low_bound = 0, high_bound = 0;
          new_length = val_length / element_length;
          if (val_length % element_length != 0)
            warning("array element type size does not divide object size in cast");
          /* FIXME-type-allocation: need a way to free this type when we are
             done with it.  */
          range_type = create_range_type ((struct type *) NULL,
                                          TYPE_TARGET_TYPE (range_type),
                                          low_bound,
                                          new_length + low_bound - 1);
          VALUE_TYPE (arg2) = create_array_type ((struct type *) NULL,
                                                 element_type, range_type);
          return arg2;
        }
    }

  if (current_language->c_style_arrays
      && TYPE_CODE (type2) == TYPE_CODE_ARRAY)
    arg2 = value_coerce_array (arg2);

  if (TYPE_CODE (type2) == TYPE_CODE_FUNC)
    arg2 = value_coerce_function (arg2);

  type2 = check_typedef (VALUE_TYPE (arg2));
  COERCE_VARYING_ARRAY (arg2, type2);
  code2 = TYPE_CODE (type2);

  if (code1 == TYPE_CODE_COMPLEX)
    return cast_into_complex (type, arg2);
  if (code1 == TYPE_CODE_BOOL)
    {
      code1 = TYPE_CODE_INT;
      convert_to_boolean = 1;
    }
  if (code1 == TYPE_CODE_CHAR)
    code1 = TYPE_CODE_INT;
  if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
    code2 = TYPE_CODE_INT;

  scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
            || code2 == TYPE_CODE_ENUM || code2 == TYPE_CODE_RANGE);

  if (   code1 == TYPE_CODE_STRUCT
      && code2 == TYPE_CODE_STRUCT
      && TYPE_NAME (type) != 0)
    {
      /* Look in the type of the source to see if it contains the
         type of the target as a superclass.  If so, we'll need to
         offset the object in addition to changing its type.  */
      value_ptr v = search_struct_field (type_name_no_tag (type),
                                         arg2, 0, type2, 1);
      if (v)
        {
          VALUE_TYPE (v) = type;
          return v;
        }
    }
  if (code1 == TYPE_CODE_FLT && scalar)
    return value_from_double (type, value_as_double (arg2));
  else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
            || code1 == TYPE_CODE_RANGE)
           && (scalar || code2 == TYPE_CODE_PTR))
    {
      LONGEST longest;
      
      if (hp_som_som_object_present &&  /* if target compiled by HP aCC */ 
          (code2 == TYPE_CODE_PTR))
        {
          unsigned int * ptr;
          value_ptr retvalp;
          
          switch (TYPE_CODE (TYPE_TARGET_TYPE (type2)))
            {
              /* With HP aCC, pointers to data members have a bias */ 
              case TYPE_CODE_MEMBER:
                retvalp = value_from_longest (type, value_as_long (arg2));
                ptr = (unsigned int *) VALUE_CONTENTS (retvalp); /* force evaluation */
                *ptr &= ~0x20000000; /* zap 29th bit to remove bias */ 
                return retvalp;

              /* While pointers to methods don't really point to a function */ 
              case TYPE_CODE_METHOD:
                error ("Pointers to methods not supported with HP aCC");

              default:
                break; /* fall out and go to normal handling */ 
            }
        }
      longest = value_as_long (arg2);
      return value_from_longest (type, convert_to_boolean ? (LONGEST) (longest ? 1 : 0) : longest);
    }
  else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
    {
      if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
        {
          struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type));
          struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
          if (   TYPE_CODE (t1) == TYPE_CODE_STRUCT
              && TYPE_CODE (t2) == TYPE_CODE_STRUCT
              && !value_logical_not (arg2))
            {
              value_ptr v;

              /* Look in the type of the source to see if it contains the
                 type of the target as a superclass.  If so, we'll need to
                 offset the pointer rather than just change its type.  */
              if (TYPE_NAME (t1) != NULL)
                {
                  v = search_struct_field (type_name_no_tag (t1),
                                           value_ind (arg2), 0, t2, 1);
                  if (v)
                    {
                      v = value_addr (v);
                      VALUE_TYPE (v) = type;
                      return v;
                    }
                }

              /* Look in the type of the target to see if it contains the
                 type of the source as a superclass.  If so, we'll need to
                 offset the pointer rather than just change its type.
                 FIXME: This fails silently with virtual inheritance.  */
              if (TYPE_NAME (t2) != NULL)
                {
                  v = search_struct_field (type_name_no_tag (t2),
                                           value_zero (t1, not_lval), 0, t1, 1);
                  if (v)
                    {
                      value_ptr v2 = value_ind (arg2);
                      VALUE_ADDRESS (v2) -= VALUE_ADDRESS (v)
                                            + VALUE_OFFSET (v);
                      v2 = value_addr (v2);
                      VALUE_TYPE (v2) = type;
                      return v2;
                    }
                }
            }
          /* No superclass found, just fall through to change ptr type.  */
        }
      VALUE_TYPE (arg2) = type;
      VALUE_ENCLOSING_TYPE (arg2) = type;  /* pai: chk_val */
      VALUE_POINTED_TO_OFFSET (arg2) = 0;  /* pai: chk_val */
      return arg2;
    }
  else if (chill_varying_type (type))
    {
      struct type *range1, *range2, *eltype1, *eltype2;
      value_ptr val;
      int count1, count2;
      LONGEST low_bound, high_bound;
      char *valaddr, *valaddr_data;
      /* For lint warning about eltype2 possibly uninitialized: */
      eltype2 = NULL;
      if (code2 == TYPE_CODE_BITSTRING)
        error ("not implemented: converting bitstring to varying type");
      if ((code2 != TYPE_CODE_ARRAY && code2 != TYPE_CODE_STRING)
          || (eltype1 = check_typedef (TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (type, 1))),
              eltype2 = check_typedef (TYPE_TARGET_TYPE (type2)),
              (TYPE_LENGTH (eltype1) != TYPE_LENGTH (eltype2)
               /* || TYPE_CODE (eltype1) != TYPE_CODE (eltype2) */ )))
        error ("Invalid conversion to varying type");
      range1 = TYPE_FIELD_TYPE (TYPE_FIELD_TYPE (type, 1), 0);
      range2 = TYPE_FIELD_TYPE (type2, 0);
      if (get_discrete_bounds (range1, &low_bound, &high_bound) < 0)
        count1 = -1;
      else
        count1 = high_bound - low_bound + 1;
      if (get_discrete_bounds (range2, &low_bound, &high_bound) < 0)
        count1 = -1, count2 = 0;  /* To force error before */
      else
        count2 = high_bound - low_bound + 1;
      if (count2 > count1)
        error ("target varying type is too small");
      val = allocate_value (type);
      valaddr = VALUE_CONTENTS_RAW (val);
      valaddr_data = valaddr + TYPE_FIELD_BITPOS (type, 1) / 8;
      /* Set val's __var_length field to count2. */
      store_signed_integer (valaddr, TYPE_LENGTH (TYPE_FIELD_TYPE (type, 0)),
                            count2);
      /* Set the __var_data field to count2 elements copied from arg2. */
      memcpy (valaddr_data, VALUE_CONTENTS (arg2),
              count2 * TYPE_LENGTH (eltype2));
      /* Zero the rest of the __var_data field of val. */
      memset (valaddr_data + count2 * TYPE_LENGTH (eltype2), '\0',
              (count1 - count2) * TYPE_LENGTH (eltype2));
      return val;
    }
  else if (VALUE_LVAL (arg2) == lval_memory)
    {
      return value_at_lazy (type, VALUE_ADDRESS (arg2) + VALUE_OFFSET (arg2),
                            VALUE_BFD_SECTION (arg2));
    }
  else if (code1 == TYPE_CODE_VOID)
    {
      return value_zero (builtin_type_void, not_lval);
    }
  else
    {
      error ("Invalid cast.");
      return 0;
    }
}

/* Create a value of type TYPE that is zero, and return it.  */

value_ptr
value_zero (type, lv)
     struct type *type;
     enum lval_type lv;
{
  register value_ptr val = allocate_value (type);

  memset (VALUE_CONTENTS (val), 0, TYPE_LENGTH (check_typedef (type)));
  VALUE_LVAL (val) = lv;

  return val;
}

/* Return a value with type TYPE located at ADDR.  

   Call value_at only if the data needs to be fetched immediately;
   if we can be 'lazy' and defer the fetch, perhaps indefinately, call
   value_at_lazy instead.  value_at_lazy simply records the address of
   the data and sets the lazy-evaluation-required flag.  The lazy flag 
   is tested in the VALUE_CONTENTS macro, which is used if and when 
   the contents are actually required. 

   Note: value_at does *NOT* handle embedded offsets; perform such
   adjustments before or after calling it. */

value_ptr
value_at (type, addr, sect)
     struct type *type;
     CORE_ADDR addr;
     asection *sect;
{
  register value_ptr val;

  if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
    error ("Attempt to dereference a generic pointer.");

  val = allocate_value (type);

#ifdef GDB_TARGET_IS_D10V
  if (TYPE_CODE (type) == TYPE_CODE_PTR
      && TYPE_TARGET_TYPE (type)
      && (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC))
    {
      /* pointer to function */
      unsigned long num;
      unsigned short snum;
      snum = read_memory_unsigned_integer (addr, 2);
      num = D10V_MAKE_IADDR(snum);
      store_address ( VALUE_CONTENTS_RAW (val), 4, num);
    }
  else if (TYPE_CODE(type) == TYPE_CODE_PTR)
    {
      /* pointer to data */
      unsigned long num;
      unsigned short snum;
      snum = read_memory_unsigned_integer (addr, 2);
      num = D10V_MAKE_DADDR(snum);
      store_address ( VALUE_CONTENTS_RAW (val), 4, num); 
    }
  else
#endif
    read_memory_section (addr, VALUE_CONTENTS_ALL_RAW (val), TYPE_LENGTH (type), sect);

  VALUE_LVAL (val) = lval_memory;
  VALUE_ADDRESS (val) = addr;
  VALUE_BFD_SECTION (val) = sect;

  return val;
}

/* Return a lazy value with type TYPE located at ADDR (cf. value_at).  */

value_ptr
value_at_lazy (type, addr, sect)
     struct type *type;
     CORE_ADDR addr;
     asection *sect;
{
  register value_ptr val;

  if (TYPE_CODE (check_typedef (type)) == TYPE_CODE_VOID)
    error ("Attempt to dereference a generic pointer.");

  val = allocate_value (type);

  VALUE_LVAL (val) = lval_memory;
  VALUE_ADDRESS (val) = addr;
  VALUE_LAZY (val) = 1;
  VALUE_BFD_SECTION (val) = sect;

  return val;
}

/* Called only from the VALUE_CONTENTS and VALUE_CONTENTS_ALL macros, 
   if the current data for a variable needs to be loaded into 
   VALUE_CONTENTS(VAL).  Fetches the data from the user's process, and 
   clears the lazy flag to indicate that the data in the buffer is valid.

   If the value is zero-length, we avoid calling read_memory, which would
   abort.  We mark the value as fetched anyway -- all 0 bytes of it.

   This function returns a value because it is used in the VALUE_CONTENTS
   macro as part of an expression, where a void would not work.  The
   value is ignored.  */

int
value_fetch_lazy (val)
     register value_ptr val;
{
  CORE_ADDR addr = VALUE_ADDRESS (val) + VALUE_OFFSET (val);
  int length = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (val));

#ifdef GDB_TARGET_IS_D10V
  struct type *type = VALUE_TYPE(val);
  if (TYPE_CODE (type) == TYPE_CODE_PTR
      && TYPE_TARGET_TYPE (type)
      && (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC))
    {
      /* pointer to function */
      unsigned long num;
      unsigned short snum;
      snum = read_memory_unsigned_integer (addr, 2);
      num = D10V_MAKE_IADDR(snum);
      store_address ( VALUE_CONTENTS_RAW (val), 4, num);
    }
  else if (TYPE_CODE(type) == TYPE_CODE_PTR)
    {
      /* pointer to data */
      unsigned long num;
      unsigned short snum;
      snum = read_memory_unsigned_integer (addr, 2);
      num = D10V_MAKE_DADDR(snum);
      store_address ( VALUE_CONTENTS_RAW (val), 4, num); 
    }
  else
#endif

  if (length)
    read_memory_section (addr, VALUE_CONTENTS_ALL_RAW (val), length,
                         VALUE_BFD_SECTION (val));
  VALUE_LAZY (val) = 0;
  return 0;
}


/* Store the contents of FROMVAL into the location of TOVAL.
   Return a new value with the location of TOVAL and contents of FROMVAL.  */

value_ptr
value_assign (toval, fromval)
     register value_ptr toval, fromval;
{
  register struct type *type;
  register value_ptr val;
  char raw_buffer[MAX_REGISTER_RAW_SIZE];
  int use_buffer = 0;

  if (!toval->modifiable)
    error ("Left operand of assignment is not a modifiable lvalue.");

  COERCE_REF (toval);

  type = VALUE_TYPE (toval);
  if (VALUE_LVAL (toval) != lval_internalvar)
    fromval = value_cast (type, fromval);
  else
    COERCE_ARRAY (fromval);
  CHECK_TYPEDEF (type);

  /* If TOVAL is a special machine register requiring conversion
     of program values to a special raw format,
     convert FROMVAL's contents now, with result in `raw_buffer',
     and set USE_BUFFER to the number of bytes to write.  */

#ifdef REGISTER_CONVERTIBLE
  if (VALUE_REGNO (toval) >= 0
      && REGISTER_CONVERTIBLE (VALUE_REGNO (toval)))
    {
      int regno = VALUE_REGNO (toval);
      if (REGISTER_CONVERTIBLE (regno))
        {
          struct type *fromtype = check_typedef (VALUE_TYPE (fromval));
          REGISTER_CONVERT_TO_RAW (fromtype, regno,
                                   VALUE_CONTENTS (fromval), raw_buffer);
          use_buffer = REGISTER_RAW_SIZE (regno);
        }
    }
#endif

  switch (VALUE_LVAL (toval))
    {
    case lval_internalvar:
      set_internalvar (VALUE_INTERNALVAR (toval), fromval);
      val = value_copy (VALUE_INTERNALVAR (toval)->value);
      VALUE_ENCLOSING_TYPE (val) = VALUE_ENCLOSING_TYPE (fromval);
      VALUE_EMBEDDED_OFFSET (val) = VALUE_EMBEDDED_OFFSET (fromval);
      VALUE_POINTED_TO_OFFSET (val) = VALUE_POINTED_TO_OFFSET (fromval);
      return val;

    case lval_internalvar_component:
      set_internalvar_component (VALUE_INTERNALVAR (toval),
                                 VALUE_OFFSET (toval),
                                 VALUE_BITPOS (toval),
                                 VALUE_BITSIZE (toval),
                                 fromval);
      break;

    case lval_memory:
      {
        char *dest_buffer;
        CORE_ADDR changed_addr;
        int changed_len;

        if (VALUE_BITSIZE (toval))
          {
            char buffer[sizeof (LONGEST)];
            /* We assume that the argument to read_memory is in units of
               host chars.  FIXME:  Is that correct?  */
            changed_len = (VALUE_BITPOS (toval)
                     + VALUE_BITSIZE (toval)
                     + HOST_CHAR_BIT - 1)
                    / HOST_CHAR_BIT;

            if (changed_len > (int) sizeof (LONGEST))
              error ("Can't handle bitfields which don't fit in a %d bit word.",
                     sizeof (LONGEST) * HOST_CHAR_BIT);

            read_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
                         buffer, changed_len);
            modify_field (buffer, value_as_long (fromval),
                          VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
            changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
            dest_buffer = buffer;
          }
        else if (use_buffer)
          {
            changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
            changed_len = use_buffer;
            dest_buffer = raw_buffer;
          }
        else
          {
            changed_addr = VALUE_ADDRESS (toval) + VALUE_OFFSET (toval);
            changed_len = TYPE_LENGTH (type);
            dest_buffer = VALUE_CONTENTS (fromval);
          }

        write_memory (changed_addr, dest_buffer, changed_len);
        if (memory_changed_hook)
          memory_changed_hook (changed_addr, changed_len);
      }
      break;

    case lval_register:
      if (VALUE_BITSIZE (toval))
        {
          char buffer[sizeof (LONGEST)];
          int len = REGISTER_RAW_SIZE (VALUE_REGNO (toval));

          if (len > (int) sizeof (LONGEST))
            error ("Can't handle bitfields in registers larger than %d bits.",
                   sizeof (LONGEST) * HOST_CHAR_BIT);

          if (VALUE_BITPOS (toval) + VALUE_BITSIZE (toval)
              > len * HOST_CHAR_BIT)
            /* Getting this right would involve being very careful about
               byte order.  */
            error ("\
Can't handle bitfield which doesn't fit in a single register.");

          read_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
                               buffer, len);
          modify_field (buffer, value_as_long (fromval),
                        VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
          write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
                                buffer, len);
        }
      else if (use_buffer)
        write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
                              raw_buffer, use_buffer);
      else
        {
          /* Do any conversion necessary when storing this type to more
             than one register.  */
#ifdef REGISTER_CONVERT_FROM_TYPE
          memcpy (raw_buffer, VALUE_CONTENTS (fromval), TYPE_LENGTH (type));
          REGISTER_CONVERT_FROM_TYPE(VALUE_REGNO (toval), type, raw_buffer);
          write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
                                raw_buffer, TYPE_LENGTH (type));
#else
          write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval),
                                VALUE_CONTENTS (fromval), TYPE_LENGTH (type));
#endif
        }
      /* Assigning to the stack pointer, frame pointer, and other
         (architecture and calling convention specific) registers may
         cause the frame cache to be out of date.  We just do this
         on all assignments to registers for simplicity; I doubt the slowdown
         matters.  */
      reinit_frame_cache ();
      break;

    case lval_reg_frame_relative:
      {
        /* value is stored in a series of registers in the frame
           specified by the structure.  Copy that value out, modify
           it, and copy it back in.  */
        int amount_to_copy = (VALUE_BITSIZE (toval) ? 1 : TYPE_LENGTH (type));
        int reg_size = REGISTER_RAW_SIZE (VALUE_FRAME_REGNUM (toval));
        int byte_offset = VALUE_OFFSET (toval) % reg_size;
        int reg_offset = VALUE_OFFSET (toval) / reg_size;
        int amount_copied;

        /* Make the buffer large enough in all cases.  */
        char *buffer = (char *) alloca (amount_to_copy
                                        + sizeof (LONGEST)
                                        + MAX_REGISTER_RAW_SIZE);

        int regno;
        struct frame_info *frame;

        /* Figure out which frame this is in currently.  */
        for (frame = get_current_frame ();
             frame && FRAME_FP (frame) != VALUE_FRAME (toval);
             frame = get_prev_frame (frame))
          ;

        if (!frame)
          error ("Value being assigned to is no longer active.");

        amount_to_copy += (reg_size - amount_to_copy % reg_size);

        /* Copy it out.  */
        for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset,
              amount_copied = 0);
             amount_copied < amount_to_copy;
             amount_copied += reg_size, regno++)
          {
            get_saved_register (buffer + amount_copied,
                                (int *)NULL, (CORE_ADDR *)NULL,
                                frame, regno, (enum lval_type *)NULL);
          }

        /* Modify what needs to be modified.  */
        if (VALUE_BITSIZE (toval))
          modify_field (buffer + byte_offset,
                        value_as_long (fromval),
                        VALUE_BITPOS (toval), VALUE_BITSIZE (toval));
        else if (use_buffer)
          memcpy (buffer + byte_offset, raw_buffer, use_buffer);
        else
          memcpy (buffer + byte_offset, VALUE_CONTENTS (fromval),
                  TYPE_LENGTH (type));

        /* Copy it back.  */
        for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset,
              amount_copied = 0);
             amount_copied < amount_to_copy;
             amount_copied += reg_size, regno++)
          {
            enum lval_type lval;
            CORE_ADDR addr;
            int optim;

            /* Just find out where to put it.  */
            get_saved_register ((char *)NULL,
                                &optim, &addr, frame, regno, &lval);
            
            if (optim)
              error ("Attempt to assign to a value that was optimized out.");
            if (lval == lval_memory)
              write_memory (addr, buffer + amount_copied, reg_size);
            else if (lval == lval_register)
              write_register_bytes (addr, buffer + amount_copied, reg_size);
            else
              error ("Attempt to assign to an unmodifiable value.");
          }

        if (register_changed_hook)
          register_changed_hook (-1);
      }
      break;
        

    default:
      error ("Left operand of assignment is not an lvalue.");
    }

  /* If the field does not entirely fill a LONGEST, then zero the sign bits.
     If the field is signed, and is negative, then sign extend. */
  if ((VALUE_BITSIZE (toval) > 0)
      && (VALUE_BITSIZE (toval) < 8 * (int) sizeof (LONGEST)))
    {
      LONGEST fieldval = value_as_long (fromval);
      LONGEST valmask = (((ULONGEST) 1) << VALUE_BITSIZE (toval)) - 1;

      fieldval &= valmask;
      if (!TYPE_UNSIGNED (type) && (fieldval & (valmask ^ (valmask >> 1))))
        fieldval |= ~valmask;

      fromval = value_from_longest (type, fieldval);
    }

  val = value_copy (toval);
  memcpy (VALUE_CONTENTS_RAW (val), VALUE_CONTENTS (fromval),
          TYPE_LENGTH (type));
  VALUE_TYPE (val) = type;
  VALUE_ENCLOSING_TYPE (val) = VALUE_ENCLOSING_TYPE (fromval);
  VALUE_EMBEDDED_OFFSET (val) = VALUE_EMBEDDED_OFFSET (fromval);
  VALUE_POINTED_TO_OFFSET (val) = VALUE_POINTED_TO_OFFSET (fromval);
  
  return val;
}

/* Extend a value VAL to COUNT repetitions of its type.  */

value_ptr
value_repeat (arg1, count)
     value_ptr arg1;
     int count;
{
  register value_ptr val;

  if (VALUE_LVAL (arg1) != lval_memory)
    error ("Only values in memory can be extended with '@'.");
  if (count < 1)
    error ("Invalid number %d of repetitions.", count);

  val = allocate_repeat_value (VALUE_ENCLOSING_TYPE (arg1), count);

  read_memory (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1),
               VALUE_CONTENTS_ALL_RAW (val),
               TYPE_LENGTH (VALUE_ENCLOSING_TYPE (val)));
  VALUE_LVAL (val) = lval_memory;
  VALUE_ADDRESS (val) = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1);

  return val;
}

value_ptr
value_of_variable (var, b)
     struct symbol *var;
     struct block *b;
{
  value_ptr val;
  struct frame_info *frame = NULL;

  if (!b)
    frame = NULL;               /* Use selected frame.  */
  else if (symbol_read_needs_frame (var))
    {
      frame = block_innermost_frame (b);
      if (!frame)
        {
          if (BLOCK_FUNCTION (b)
              && SYMBOL_SOURCE_NAME (BLOCK_FUNCTION (b)))
            error ("No frame is currently executing in block %s.",
                   SYMBOL_SOURCE_NAME (BLOCK_FUNCTION (b)));
          else
            error ("No frame is currently executing in specified block");
        }
    }

  val = read_var_value (var, frame);
  if (!val)
    error ("Address of symbol \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var));

  return val;
}

/* Given a value which is an array, return a value which is a pointer to its
   first element, regardless of whether or not the array has a nonzero lower
   bound.

   FIXME:  A previous comment here indicated that this routine should be
   substracting the array's lower bound.  It's not clear to me that this
   is correct.  Given an array subscripting operation, it would certainly
   work to do the adjustment here, essentially computing:

   (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])

   However I believe a more appropriate and logical place to account for
   the lower bound is to do so in value_subscript, essentially computing:

   (&array[0] + ((index - lowerbound) * sizeof array[0]))

   As further evidence consider what would happen with operations other
   than array subscripting, where the caller would get back a value that
   had an address somewhere before the actual first element of the array,
   and the information about the lower bound would be lost because of
   the coercion to pointer type.
   */

value_ptr
value_coerce_array (arg1)
     value_ptr arg1;
{
  register struct type *type = check_typedef (VALUE_TYPE (arg1));

  if (VALUE_LVAL (arg1) != lval_memory)
    error ("Attempt to take address of value not located in memory.");

  return value_from_longest (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
                       (LONGEST) (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
}

/* Given a value which is a function, return a value which is a pointer
   to it.  */

value_ptr
value_coerce_function (arg1)
     value_ptr arg1;
{
  value_ptr retval;

  if (VALUE_LVAL (arg1) != lval_memory)
    error ("Attempt to take address of value not located in memory.");

  retval = value_from_longest (lookup_pointer_type (VALUE_TYPE (arg1)),
                               (LONGEST) (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1)));
  VALUE_BFD_SECTION (retval) = VALUE_BFD_SECTION (arg1);
  return retval;
}  

/* Return a pointer value for the object for which ARG1 is the contents.  */

value_ptr
value_addr (arg1)
     value_ptr arg1;
{
  value_ptr arg2;

  struct type *type = check_typedef (VALUE_TYPE (arg1));
  if (TYPE_CODE (type) == TYPE_CODE_REF)
    {
      /* Copy the value, but change the type from (T&) to (T*).
         We keep the same location information, which is efficient,
         and allows &(&X) to get the location containing the reference. */
      arg2 = value_copy (arg1);
      VALUE_TYPE (arg2) = lookup_pointer_type (TYPE_TARGET_TYPE (type));
      return arg2;
    }
  if (TYPE_CODE (type) == TYPE_CODE_FUNC)
    return value_coerce_function (arg1);

  if (VALUE_LVAL (arg1) != lval_memory)
    error ("Attempt to take address of value not located in memory.");

  /* Get target memory address */  
  arg2 = value_from_longest (lookup_pointer_type (VALUE_TYPE (arg1)),
                               (LONGEST) (VALUE_ADDRESS (arg1) 
                                          + VALUE_OFFSET (arg1)
                                          + VALUE_EMBEDDED_OFFSET (arg1)));

  /* This may be a pointer to a base subobject; so remember the
     full derived object's type ... */ 
  VALUE_ENCLOSING_TYPE (arg2) = lookup_pointer_type (VALUE_ENCLOSING_TYPE (arg1));
  /* ... and also the relative position of the subobject in the full object */ 
  VALUE_POINTED_TO_OFFSET (arg2) = VALUE_EMBEDDED_OFFSET (arg1);  
  VALUE_BFD_SECTION (arg2) = VALUE_BFD_SECTION (arg1);
  return arg2;
}

/* Given a value of a pointer type, apply the C unary * operator to it.  */

value_ptr
value_ind (arg1)
     value_ptr arg1;
{
  struct type *base_type;
  value_ptr arg2;
  value_ptr real_val;

  COERCE_ARRAY (arg1);

  base_type = check_typedef (VALUE_TYPE (arg1));

  if (TYPE_CODE (base_type) == TYPE_CODE_MEMBER)
    error ("not implemented: member types in value_ind");

  /* Allow * on an integer so we can cast it to whatever we want.
     This returns an int, which seems like the most C-like thing
     to do.  "long long" variables are rare enough that
     BUILTIN_TYPE_LONGEST would seem to be a mistake.  */
  if (TYPE_CODE (base_type) == TYPE_CODE_INT)
    return value_at (builtin_type_int,
                     (CORE_ADDR) value_as_long (arg1),
                     VALUE_BFD_SECTION (arg1));
  else if (TYPE_CODE (base_type) == TYPE_CODE_PTR)
    {
      struct type *enc_type;
      /* We may be pointing to something embedded in a larger object */
      /* Get the real type of the enclosing object */ 
      enc_type = check_typedef (VALUE_ENCLOSING_TYPE (arg1));
      enc_type = TYPE_TARGET_TYPE (enc_type);
      /* Retrieve the enclosing object pointed to */ 
      arg2 =  value_at_lazy (enc_type, 
                             value_as_pointer (arg1) - VALUE_POINTED_TO_OFFSET (arg1),
                             VALUE_BFD_SECTION (arg1));
      /* Re-adjust type */ 
      VALUE_TYPE (arg2) = TYPE_TARGET_TYPE (base_type);
      /* Add embedding info */
      VALUE_ENCLOSING_TYPE (arg2) = enc_type;
      VALUE_EMBEDDED_OFFSET (arg2) = VALUE_POINTED_TO_OFFSET (arg1);

      /* We may be pointing to an object of some derived type */
      arg2 = value_full_object (arg2, NULL, 0, 0, 0);
      return arg2;
    }

  error ("Attempt to take contents of a non-pointer value.");
  return 0;  /* For lint -- never reached */
}
\f
/* Pushing small parts of stack frames.  */

/* Push one word (the size of object that a register holds).  */

CORE_ADDR
push_word (sp, word)
     CORE_ADDR sp;
     ULONGEST word;
{
  register int len = REGISTER_SIZE;
  char buffer[MAX_REGISTER_RAW_SIZE];

  store_unsigned_integer (buffer, len, word);
  if (INNER_THAN (1, 2))
    {
      /* stack grows downward */
      sp -= len;
      write_memory (sp, buffer, len);
    }
  else
    {
      /* stack grows upward */
      write_memory (sp, buffer, len);
      sp += len;
    }

  return sp;
}

/* Push LEN bytes with data at BUFFER.  */

CORE_ADDR
push_bytes (sp, buffer, len)
     CORE_ADDR sp;
     char *buffer;
     int len;
{
  if (INNER_THAN (1, 2))
    {
      /* stack grows downward */
      sp -= len;
      write_memory (sp, buffer, len);
    }
  else
    {
      /* stack grows upward */
      write_memory (sp, buffer, len);
      sp += len;
    }

  return sp;
}

/* Push onto the stack the specified value VALUE.  */

#ifndef PUSH_ARGUMENTS

static CORE_ADDR
value_push (sp, arg)
     register CORE_ADDR sp;
     value_ptr arg;
{
  register int len = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (arg));

  if (INNER_THAN (1, 2))
    {
      /* stack grows downward */
      sp -= len;
      write_memory (sp, VALUE_CONTENTS_ALL (arg), len);
    }
  else
    {
      /* stack grows upward */
      write_memory (sp, VALUE_CONTENTS_ALL (arg), len);
      sp += len;
    }

  return sp;
}

#endif  /* !PUSH_ARGUMENTS */

#ifdef CALL_DUMMY
/* Perform the standard coercions that are specified
   for arguments to be passed to C functions.

   If PARAM_TYPE is non-NULL, it is the expected parameter type.
   IS_PROTOTYPED is non-zero if the function declaration is prototyped.  */

static value_ptr
value_arg_coerce (arg, param_type, is_prototyped)
     value_ptr arg;
     struct type *param_type;
     int is_prototyped;
{
  register struct type *arg_type = check_typedef (VALUE_TYPE (arg));
  register struct type *type
    = param_type ? check_typedef (param_type) : arg_type;

  switch (TYPE_CODE (type))
    {
    case TYPE_CODE_REF:
      if (TYPE_CODE (arg_type) != TYPE_CODE_REF)
        {
          arg = value_addr (arg);
          VALUE_TYPE (arg) = param_type;
          return arg;
        }
      break;
    case TYPE_CODE_INT:
    case TYPE_CODE_CHAR:
    case TYPE_CODE_BOOL:
    case TYPE_CODE_ENUM:
      /* If we don't have a prototype, coerce to integer type if necessary.  */
      if (!is_prototyped)
        {
          if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
            type = builtin_type_int;
        }
      /* Currently all target ABIs require at least the width of an integer
         type for an argument.  We may have to conditionalize the following
         type coercion for future targets.  */
      if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_int))
        type = builtin_type_int;
      break;
    case TYPE_CODE_FLT:
      /* FIXME: We should always convert floats to doubles in the
         non-prototyped case.  As many debugging formats include
         no information about prototyping, we have to live with
         COERCE_FLOAT_TO_DOUBLE for now.  */
      if (!is_prototyped && COERCE_FLOAT_TO_DOUBLE)
        {
          if (TYPE_LENGTH (type) < TYPE_LENGTH (builtin_type_double))
            type = builtin_type_double;
          else if (TYPE_LENGTH (type) > TYPE_LENGTH (builtin_type_double))
            type = builtin_type_long_double;
        }
      break;
    case TYPE_CODE_FUNC:
      type = lookup_pointer_type (type);
      break;
    case TYPE_CODE_ARRAY:
      if (current_language->c_style_arrays)
        type = lookup_pointer_type (TYPE_TARGET_TYPE (type));
      break;
    case TYPE_CODE_UNDEF:
    case TYPE_CODE_PTR:
    case TYPE_CODE_STRUCT:
    case TYPE_CODE_UNION:
    case TYPE_CODE_VOID:
    case TYPE_CODE_SET:
    case TYPE_CODE_RANGE:
    case TYPE_CODE_STRING:
    case TYPE_CODE_BITSTRING:
    case TYPE_CODE_ERROR:
    case TYPE_CODE_MEMBER:
    case TYPE_CODE_METHOD:
    case TYPE_CODE_COMPLEX:
    default:
      break;
    }

  return value_cast (type, arg);
}

/* Determine a function's address and its return type from its value. 
   Calls error() if the function is not valid for calling.  */

static CORE_ADDR
find_function_addr (function, retval_type)
     value_ptr function;
     struct type **retval_type;
{
  register struct type *ftype = check_typedef (VALUE_TYPE (function));
  register enum type_code code = TYPE_CODE (ftype);
  struct type *value_type;
  CORE_ADDR funaddr;

  /* If it's a member function, just look at the function
     part of it.  */

  /* Determine address to call.  */
  if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD)
    {
      funaddr = VALUE_ADDRESS (function);
      value_type = TYPE_TARGET_TYPE (ftype);
    }
  else if (code == TYPE_CODE_PTR)
    {
      funaddr = value_as_pointer (function);
      ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
      if (TYPE_CODE (ftype) == TYPE_CODE_FUNC
          || TYPE_CODE (ftype) == TYPE_CODE_METHOD)
        {
#ifdef CONVERT_FROM_FUNC_PTR_ADDR
          /* FIXME: This is a workaround for the unusual function
             pointer representation on the RS/6000, see comment
             in config/rs6000/tm-rs6000.h  */
          funaddr = CONVERT_FROM_FUNC_PTR_ADDR (funaddr);
#endif
          value_type = TYPE_TARGET_TYPE (ftype);
        }
      else
        value_type = builtin_type_int;
    }
  else if (code == TYPE_CODE_INT)
    {
      /* Handle the case of functions lacking debugging info.
         Their values are characters since their addresses are char */
      if (TYPE_LENGTH (ftype) == 1)
        funaddr = value_as_pointer (value_addr (function));
      else
        /* Handle integer used as address of a function.  */
        funaddr = (CORE_ADDR) value_as_long (function);

      value_type = builtin_type_int;
    }
  else
    error ("Invalid data type for function to be called.");

  *retval_type = value_type;
  return funaddr;
}

/* All this stuff with a dummy frame may seem unnecessarily complicated
   (why not just save registers in GDB?).  The purpose of pushing a dummy
   frame which looks just like a real frame is so that if you call a
   function and then hit a breakpoint (get a signal, etc), "backtrace"
   will look right.  Whether the backtrace needs to actually show the
   stack at the time the inferior function was called is debatable, but
   it certainly needs to not display garbage.  So if you are contemplating
   making dummy frames be different from normal frames, consider that.  */

/* Perform a function call in the inferior.
   ARGS is a vector of values of arguments (NARGS of them).
   FUNCTION is a value, the function to be called.
   Returns a value representing what the function returned.
   May fail to return, if a breakpoint or signal is hit
   during the execution of the function.

   ARGS is modified to contain coerced values. */

value_ptr
call_function_by_hand (function, nargs, args)
     value_ptr function;
     int nargs;
     value_ptr *args;
{
  register CORE_ADDR sp;
  register int i;
  CORE_ADDR start_sp;
  /* CALL_DUMMY is an array of words (REGISTER_SIZE), but each word
     is in host byte order.  Before calling FIX_CALL_DUMMY, we byteswap it
     and remove any extra bytes which might exist because ULONGEST is
     bigger than REGISTER_SIZE.  

     NOTE: This is pretty wierd, as the call dummy is actually a
           sequence of instructions.  But CISC machines will have
           to pack the instructions into REGISTER_SIZE units (and
           so will RISC machines for which INSTRUCTION_SIZE is not
           REGISTER_SIZE). */

  static ULONGEST dummy[] = CALL_DUMMY;
  char dummy1[REGISTER_SIZE * sizeof dummy / sizeof (ULONGEST)];
  CORE_ADDR old_sp;
  struct type *value_type;
  unsigned char struct_return;
  CORE_ADDR struct_addr = 0;
  struct inferior_status inf_status;
  struct cleanup *old_chain;
  CORE_ADDR funaddr;
  int using_gcc;        /* Set to version of gcc in use, or zero if not gcc */
  CORE_ADDR real_pc;
  struct type *param_type = NULL;
  struct type *ftype = check_typedef (SYMBOL_TYPE (function));

  if (!target_has_execution)
    noprocess();

  save_inferior_status (&inf_status, 1);
  old_chain = make_cleanup ((make_cleanup_func) restore_inferior_status, 
                            &inf_status);

  /* PUSH_DUMMY_FRAME is responsible for saving the inferior registers
     (and POP_FRAME for restoring them).  (At least on most machines)
     they are saved on the stack in the inferior.  */
  PUSH_DUMMY_FRAME;

  old_sp = sp = read_sp ();

  if (INNER_THAN (1, 2))
    {
      /* Stack grows down */
      sp -= sizeof dummy1;
      start_sp = sp;
    }
  else
    {
      /* Stack grows up */
      start_sp = sp;
      sp += sizeof dummy1;
    }

  funaddr = find_function_addr (function, &value_type);
  CHECK_TYPEDEF (value_type);

  {
    struct block *b = block_for_pc (funaddr);
    /* If compiled without -g, assume GCC 2.  */
    using_gcc = (b == NULL ? 2 : BLOCK_GCC_COMPILED (b));
  }

  /* Are we returning a value using a structure return or a normal
     value return? */

  struct_return = using_struct_return (function, funaddr, value_type,
                                       using_gcc);

  /* Create a call sequence customized for this function
     and the number of arguments for it.  */
  for (i = 0; i < (int) (sizeof (dummy) / sizeof (dummy[0])); i++)
    store_unsigned_integer (&dummy1[i * REGISTER_SIZE],
                            REGISTER_SIZE,
                            (ULONGEST)dummy[i]);

#ifdef GDB_TARGET_IS_HPPA
  real_pc = FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
                            value_type, using_gcc);
#else
  FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args,
                  value_type, using_gcc);
  real_pc = start_sp;
#endif

#if CALL_DUMMY_LOCATION == ON_STACK
  write_memory (start_sp, (char *)dummy1, sizeof dummy1);
#endif /* On stack.  */

#if CALL_DUMMY_LOCATION == BEFORE_TEXT_END
  /* Convex Unix prohibits executing in the stack segment. */
  /* Hope there is empty room at the top of the text segment. */
  {
    extern CORE_ADDR text_end;
    static checked = 0;
    if (!checked)
      for (start_sp = text_end - sizeof dummy1; start_sp < text_end; ++start_sp)
        if (read_memory_integer (start_sp, 1) != 0)
          error ("text segment full -- no place to put call");
    checked = 1;
    sp = old_sp;
    real_pc = text_end - sizeof dummy1;
    write_memory (real_pc, (char *)dummy1, sizeof dummy1);
  }
#endif /* Before text_end.  */

#if CALL_DUMMY_LOCATION == AFTER_TEXT_END
  {
    extern CORE_ADDR text_end;
    int errcode;
    sp = old_sp;
    real_pc = text_end;
    errcode = target_write_memory (real_pc, (char *)dummy1, sizeof dummy1);
    if (errcode != 0)
      error ("Cannot write text segment -- call_function failed");
  }
#endif /* After text_end.  */

#if CALL_DUMMY_LOCATION == AT_ENTRY_POINT
  real_pc = funaddr;
#endif /* At entry point.  */

#ifdef lint
  sp = old_sp;          /* It really is used, for some ifdef's... */
#endif

  if (nargs < TYPE_NFIELDS (ftype))
    error ("too few arguments in function call");

  for (i = nargs - 1; i >= 0; i--)
    {
      /* If we're off the end of the known arguments, do the standard
         promotions.  FIXME: if we had a prototype, this should only
         be allowed if ... were present.  */
      if (i >= TYPE_NFIELDS (ftype))
        args[i] = value_arg_coerce (args[i], NULL, 0);

      else 
        {
          int is_prototyped = TYPE_FLAGS (ftype) & TYPE_FLAG_PROTOTYPED;
          param_type = TYPE_FIELD_TYPE (ftype, i);

          args[i] = value_arg_coerce (args[i], param_type, is_prototyped);
        }

      /*elz: this code is to handle the case in which the function to be called 
        has a pointer to function as parameter and the corresponding actual argument 
        is the address of a function and not a pointer to function variable.
        In aCC compiled code, the calls through pointers to functions (in the body
        of the function called by hand) are made via $$dyncall_external which
        requires some registers setting, this is taken care of if we call 
        via a function pointer variable, but not via a function address. 
        In cc this is not a problem. */

      if (using_gcc == 0)
        if (param_type)
          /* if this parameter is a pointer to function*/
          if (TYPE_CODE (param_type) == TYPE_CODE_PTR)
            if (TYPE_CODE (param_type->target_type) == TYPE_CODE_FUNC)
              /* elz: FIXME here should go the test about the compiler used 
                    to compile the target. We want to issue the error
                    message only if the compiler used was HP's aCC. 
                    If we used HP's cc, then there is no problem and no need 
                    to return at this point */
              if (using_gcc == 0) /* && compiler == aCC*/
                /* go see if the actual parameter is a variable of type
                pointer to function or just a function */
                if (args[i]->lval == not_lval)
                  {
                    char *arg_name;
                    if (find_pc_partial_function((CORE_ADDR)args[i]->aligner.contents[0], &arg_name, NULL, NULL))
                      error("\
You cannot use function <%s> as argument. \n\
You must use a pointer to function type variable. Command ignored.", arg_name);
                  }   
    }

#if defined (REG_STRUCT_HAS_ADDR)
  {
    /* This is a machine like the sparc, where we may need to pass a pointer
       to the structure, not the structure itself.  */
    for (i = nargs - 1; i >= 0; i--)
      {
        struct type *arg_type = check_typedef (VALUE_TYPE (args[i]));
        if ((TYPE_CODE (arg_type) == TYPE_CODE_STRUCT
             || TYPE_CODE (arg_type) == TYPE_CODE_UNION
             || TYPE_CODE (arg_type) == TYPE_CODE_ARRAY
             || TYPE_CODE (arg_type) == TYPE_CODE_STRING
             || TYPE_CODE (arg_type) == TYPE_CODE_BITSTRING
             || TYPE_CODE (arg_type) == TYPE_CODE_SET
             || (TYPE_CODE (arg_type) == TYPE_CODE_FLT
                 && TYPE_LENGTH (arg_type) > 8)
             )
          && REG_STRUCT_HAS_ADDR (using_gcc, arg_type))
          {
            CORE_ADDR addr;
            int len; /*  = TYPE_LENGTH (arg_type); */ 
            int aligned_len;
            arg_type = check_typedef (VALUE_ENCLOSING_TYPE (args[i])); 
            len = TYPE_LENGTH (arg_type);

#ifdef STACK_ALIGN
  /* MVS 11/22/96: I think at least some of this stack_align code is
     really broken.  Better to let PUSH_ARGUMENTS adjust the stack in
     a target-defined manner.  */
            aligned_len = STACK_ALIGN (len);
#else
            aligned_len = len;
#endif
            if (INNER_THAN (1, 2))
              {
                /* stack grows downward */
                sp -= aligned_len;
              }
            else
              {
                /* The stack grows up, so the address of the thing we push
                   is the stack pointer before we push it.  */
                addr = sp;
              }
            /* Push the structure.  */
            write_memory (sp, VALUE_CONTENTS_ALL (args[i]), len);
            if (INNER_THAN (1, 2))
              {
                /* The stack grows down, so the address of the thing we push
                   is the stack pointer after we push it.  */
                addr = sp;
              }
            else
              {
                /* stack grows upward */
                sp += aligned_len;
              }
            /* The value we're going to pass is the address of the thing
               we just pushed.  */
            /*args[i] = value_from_longest (lookup_pointer_type (value_type),
                                          (LONGEST) addr);*/
            args[i] = value_from_longest (lookup_pointer_type (arg_type), 
                                          (LONGEST) addr);
          }
      }
  }
#endif /* REG_STRUCT_HAS_ADDR.  */

  /* Reserve space for the return structure to be written on the
     stack, if necessary */

  if (struct_return)
    {
      int len = TYPE_LENGTH (value_type);
#ifdef STACK_ALIGN
  /* MVS 11/22/96: I think at least some of this stack_align code is
     really broken.  Better to let PUSH_ARGUMENTS adjust the stack in
     a target-defined manner.  */
      len = STACK_ALIGN (len);
#endif
      if (INNER_THAN (1, 2))
        {
          /* stack grows downward */
          sp -= len;
          struct_addr = sp;
        }
      else
        {
          /* stack grows upward */
          struct_addr = sp;
          sp += len;
        }
    }

/* elz: on HPPA no need for this extra alignment, maybe it is needed
   on other architectures. This is because all the alignment is taken care
   of in the above code (ifdef REG_STRUCT_HAS_ADDR) and in 
   hppa_push_arguments*/
#ifndef NO_EXTRA_ALIGNMENT_NEEDED

#if defined(STACK_ALIGN)
  /* MVS 11/22/96: I think at least some of this stack_align code is
     really broken.  Better to let PUSH_ARGUMENTS adjust the stack in
     a target-defined manner.  */
  if (INNER_THAN (1, 2))
    {
      /* If stack grows down, we must leave a hole at the top. */
      int len = 0;

      for (i = nargs - 1; i >= 0; i--)
        len += TYPE_LENGTH (VALUE_ENCLOSING_TYPE (args[i]));
#ifdef CALL_DUMMY_STACK_ADJUST
      len += CALL_DUMMY_STACK_ADJUST;
#endif
      sp -= STACK_ALIGN (len) - len;
    }
#endif /* STACK_ALIGN */
#endif /* NO_EXTRA_ALIGNMENT_NEEDED */

#ifdef PUSH_ARGUMENTS
  PUSH_ARGUMENTS(nargs, args, sp, struct_return, struct_addr);
#else /* !PUSH_ARGUMENTS */
  for (i = nargs - 1; i >= 0; i--)
    sp = value_push (sp, args[i]);
#endif /* !PUSH_ARGUMENTS */

#ifdef PUSH_RETURN_ADDRESS      /* for targets that use no CALL_DUMMY */
  /* There are a number of targets now which actually don't write any
     CALL_DUMMY instructions into the target, but instead just save the
     machine state, push the arguments, and jump directly to the callee
     function.  Since this doesn't actually involve executing a JSR/BSR
     instruction, the return address must be set up by hand, either by
     pushing onto the stack or copying into a return-address register
     as appropriate.  Formerly this has been done in PUSH_ARGUMENTS, 
     but that's overloading its functionality a bit, so I'm making it
     explicit to do it here.  */
  sp = PUSH_RETURN_ADDRESS(real_pc, sp);
#endif  /* PUSH_RETURN_ADDRESS */

#if defined(STACK_ALIGN)
  if (! INNER_THAN (1, 2))
    {
      /* If stack grows up, we must leave a hole at the bottom, note
         that sp already has been advanced for the arguments!  */
#ifdef CALL_DUMMY_STACK_ADJUST
      sp += CALL_DUMMY_STACK_ADJUST;
#endif
      sp = STACK_ALIGN (sp);
    }
#endif /* STACK_ALIGN */

/* XXX This seems wrong.  For stacks that grow down we shouldn't do
   anything here!  */
  /* MVS 11/22/96: I think at least some of this stack_align code is
     really broken.  Better to let PUSH_ARGUMENTS adjust the stack in
     a target-defined manner.  */
#ifdef CALL_DUMMY_STACK_ADJUST
  if (INNER_THAN (1, 2))
    {
      /* stack grows downward */
      sp -= CALL_DUMMY_STACK_ADJUST;
    }
#endif /* CALL_DUMMY_STACK_ADJUST */

  /* Store the address at which the structure is supposed to be
     written.  Note that this (and the code which reserved the space
     above) assumes that gcc was used to compile this function.  Since
     it doesn't cost us anything but space and if the function is pcc
     it will ignore this value, we will make that assumption.

     Also note that on some machines (like the sparc) pcc uses a 
     convention like gcc's.  */

  if (struct_return)
    STORE_STRUCT_RETURN (struct_addr, sp);

  /* Write the stack pointer.  This is here because the statements above
     might fool with it.  On SPARC, this write also stores the register
     window into the right place in the new stack frame, which otherwise
     wouldn't happen.  (See store_inferior_registers in sparc-nat.c.)  */
  write_sp (sp);

  {
    char retbuf[REGISTER_BYTES];
    char *name;
    struct symbol *symbol;

    name = NULL;
    symbol = find_pc_function (funaddr);
    if (symbol)
      {
        name = SYMBOL_SOURCE_NAME (symbol);
      }
    else
      {
        /* Try the minimal symbols.  */
        struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (funaddr);

        if (msymbol)
          {
            name = SYMBOL_SOURCE_NAME (msymbol);
          }
      }
    if (name == NULL)
      {
        char format[80];
        sprintf (format, "at %s", local_hex_format ());
        name = alloca (80);
        /* FIXME-32x64: assumes funaddr fits in a long.  */
        sprintf (name, format, (unsigned long) funaddr);
      }

    /* Execute the stack dummy routine, calling FUNCTION.
       When it is done, discard the empty frame
       after storing the contents of all regs into retbuf.  */
    if (run_stack_dummy (real_pc + CALL_DUMMY_START_OFFSET, retbuf))
      {
        /* We stopped somewhere besides the call dummy.  */

        /* If we did the cleanups, we would print a spurious error message
           (Unable to restore previously selected frame), would write the
           registers from the inf_status (which is wrong), and would do other
           wrong things (like set stop_bpstat to the wrong thing).  */
        discard_cleanups (old_chain);
        /* Prevent memory leak.  */
        bpstat_clear (&inf_status.stop_bpstat);

        /* The following error message used to say "The expression
           which contained the function call has been discarded."  It
           is a hard concept to explain in a few words.  Ideally, GDB
           would be able to resume evaluation of the expression when
           the function finally is done executing.  Perhaps someday
           this will be implemented (it would not be easy).  */

        /* FIXME: Insert a bunch of wrap_here; name can be very long if it's
           a C++ name with arguments and stuff.  */
        error ("\
The program being debugged stopped while in a function called from GDB.\n\
When the function (%s) is done executing, GDB will silently\n\
stop (instead of continuing to evaluate the expression containing\n\
the function call).", name);
      }

    do_cleanups (old_chain);

    /* Figure out the value returned by the function.  */
/* elz: I defined this new macro for the hppa architecture only.
   this gives us a way to get the value returned by the function from the stack,
   at the same address we told the function to put it.
   We cannot assume on the pa that r28 still contains the address of the returned
   structure. Usually this will be overwritten by the callee.
   I don't know about other architectures, so I defined this macro
*/

#ifdef VALUE_RETURNED_FROM_STACK
    if (struct_return)
      return (value_ptr) VALUE_RETURNED_FROM_STACK (value_type, struct_addr);
#endif

    return value_being_returned (value_type, retbuf, struct_return);
  }
}
#else /* no CALL_DUMMY.  */
value_ptr
call_function_by_hand (function, nargs, args)
     value_ptr function;
     int nargs;
     value_ptr *args;
{
  error ("Cannot invoke functions on this machine.");
}
#endif /* no CALL_DUMMY.  */

\f
/* Create a value for an array by allocating space in the inferior, copying
   the data into that space, and then setting up an array value.

   The array bounds are set from LOWBOUND and HIGHBOUND, and the array is
   populated from the values passed in ELEMVEC.

   The element type of the array is inherited from the type of the
   first element, and all elements must have the same size (though we
   don't currently enforce any restriction on their types). */

value_ptr
value_array (lowbound, highbound, elemvec)
     int lowbound;
     int highbound;
     value_ptr *elemvec;
{
  int nelem;
  int idx;
  unsigned int typelength;
  value_ptr val;
  struct type *rangetype;
  struct type *arraytype;
  CORE_ADDR addr;

  /* Validate that the bounds are reasonable and that each of the elements
     have the same size. */

  nelem = highbound - lowbound + 1;
  if (nelem <= 0)
    {
      error ("bad array bounds (%d, %d)", lowbound, highbound);
    }
  typelength = TYPE_LENGTH (VALUE_ENCLOSING_TYPE (elemvec[0]));
  for (idx = 1; idx < nelem; idx++)
    {
      if (TYPE_LENGTH (VALUE_ENCLOSING_TYPE (elemvec[idx])) != typelength)
        {
          error ("array elements must all be the same size");
        }
    }

  rangetype = create_range_type ((struct type *) NULL, builtin_type_int,
                                 lowbound, highbound);
  arraytype = create_array_type ((struct type *) NULL, 
                                 VALUE_ENCLOSING_TYPE (elemvec[0]), rangetype);

  if (!current_language->c_style_arrays)
    {
      val = allocate_value (arraytype);
      for (idx = 0; idx < nelem; idx++)
        {
          memcpy (VALUE_CONTENTS_ALL_RAW (val) + (idx * typelength),
                  VALUE_CONTENTS_ALL (elemvec[idx]),
                  typelength);
        }
      VALUE_BFD_SECTION (val) = VALUE_BFD_SECTION (elemvec[0]);
      return val;
    }

  /* Allocate space to store the array in the inferior, and then initialize
     it by copying in each element.  FIXME:  Is it worth it to create a
     local buffer in which to collect each value and then write all the
     bytes in one operation? */

  addr = allocate_space_in_inferior (nelem * typelength);
  for (idx = 0; idx < nelem; idx++)
    {
      write_memory (addr + (idx * typelength), VALUE_CONTENTS_ALL (elemvec[idx]),
                    typelength);
    }

  /* Create the array type and set up an array value to be evaluated lazily. */

  val = value_at_lazy (arraytype, addr, VALUE_BFD_SECTION (elemvec[0]));
  return (val);
}

/* Create a value for a string constant by allocating space in the inferior,
   copying the data into that space, and returning the address with type
   TYPE_CODE_STRING.  PTR points to the string constant data; LEN is number
   of characters.
   Note that string types are like array of char types with a lower bound of
   zero and an upper bound of LEN - 1.  Also note that the string may contain
   embedded null bytes. */

value_ptr
value_string (ptr, len)
     char *ptr;
     int len;
{
  value_ptr val;
  int lowbound = current_language->string_lower_bound;
  struct type *rangetype = create_range_type ((struct type *) NULL,
                                              builtin_type_int,
                                              lowbound, len + lowbound - 1);
  struct type *stringtype
    = create_string_type ((struct type *) NULL, rangetype);
  CORE_ADDR addr;

  if (current_language->c_style_arrays == 0)
    {
      val = allocate_value (stringtype);
      memcpy (VALUE_CONTENTS_RAW (val), ptr, len);
      return val;
    }


  /* Allocate space to store the string in the inferior, and then
     copy LEN bytes from PTR in gdb to that address in the inferior. */

  addr = allocate_space_in_inferior (len);
  write_memory (addr, ptr, len);

  val = value_at_lazy (stringtype, addr, NULL);
  return (val);
}

value_ptr
value_bitstring (ptr, len)
     char *ptr;
     int len;
{
  value_ptr val;
  struct type *domain_type = create_range_type (NULL, builtin_type_int,
                                                0, len - 1);
  struct type *type = create_set_type ((struct type*) NULL, domain_type);
  TYPE_CODE (type) = TYPE_CODE_BITSTRING;
  val = allocate_value (type);
  memcpy (VALUE_CONTENTS_RAW (val), ptr, TYPE_LENGTH (type));
  return val;
}
\f
/* See if we can pass arguments in T2 to a function which takes arguments
   of types T1.  Both t1 and t2 are NULL-terminated vectors.  If some
   arguments need coercion of some sort, then the coerced values are written
   into T2.  Return value is 0 if the arguments could be matched, or the
   position at which they differ if not.

   STATICP is nonzero if the T1 argument list came from a
   static member function.

   For non-static member functions, we ignore the first argument,
   which is the type of the instance variable.  This is because we want
   to handle calls with objects from derived classes.  This is not
   entirely correct: we should actually check to make sure that a
   requested operation is type secure, shouldn't we?  FIXME.  */

static int
typecmp (staticp, t1, t2)
     int staticp;
     struct type *t1[];
     value_ptr t2[];
{
  int i;

  if (t2 == 0)
    return 1;
  if (staticp && t1 == 0)
    return t2[1] != 0;
  if (t1 == 0)
    return 1;
  if (TYPE_CODE (t1[0]) == TYPE_CODE_VOID) return 0;
  if (t1[!staticp] == 0) return 0;
  for (i = !staticp; t1[i] && TYPE_CODE (t1[i]) != TYPE_CODE_VOID; i++)
    {
    struct type *tt1, *tt2;
      if (! t2[i])
        return i+1;
      tt1 = check_typedef (t1[i]);
      tt2 = check_typedef (VALUE_TYPE(t2[i]));
      if (TYPE_CODE (tt1) == TYPE_CODE_REF
          /* We should be doing hairy argument matching, as below.  */
          && (TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (tt1))) == TYPE_CODE (tt2)))
        {
          if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
            t2[i] = value_coerce_array (t2[i]);
          else
            t2[i] = value_addr (t2[i]);
          continue;
        }

      while (TYPE_CODE (tt1) == TYPE_CODE_PTR
          && (   TYPE_CODE (tt2) == TYPE_CODE_ARRAY
              || TYPE_CODE (tt2) == TYPE_CODE_PTR))
        {
           tt1 = check_typedef (TYPE_TARGET_TYPE(tt1)); 
           tt2 = check_typedef (TYPE_TARGET_TYPE(tt2));
        }
      if (TYPE_CODE(tt1) == TYPE_CODE(tt2)) continue;
      /* Array to pointer is a `trivial conversion' according to the ARM.  */

      /* We should be doing much hairier argument matching (see section 13.2
         of the ARM), but as a quick kludge, just check for the same type
         code.  */
      if (TYPE_CODE (t1[i]) != TYPE_CODE (VALUE_TYPE (t2[i])))
        return i+1;
    }
  if (!t1[i]) return 0;
  return t2[i] ? i+1 : 0;
}

/* Helper function used by value_struct_elt to recurse through baseclasses.
   Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
   and search in it assuming it has (class) type TYPE.
   If found, return value, else return NULL.

   If LOOKING_FOR_BASECLASS, then instead of looking for struct fields,
   look for a baseclass named NAME.  */

static value_ptr
search_struct_field (name, arg1, offset, type, looking_for_baseclass)
     char *name;
     register value_ptr arg1;
     int offset;
     register struct type *type;
     int looking_for_baseclass;
{
  int i;
  int nbases = TYPE_N_BASECLASSES (type);

  CHECK_TYPEDEF (type);

  if (! looking_for_baseclass)
    for (i = TYPE_NFIELDS (type) - 1; i >= nbases; i--)
      {
        char *t_field_name = TYPE_FIELD_NAME (type, i);

        if (t_field_name && STREQ (t_field_name, name))
          {
            value_ptr v;
            if (TYPE_FIELD_STATIC (type, i))
              v = value_static_field (type, i);
            else
              v = value_primitive_field (arg1, offset, i, type);
            if (v == 0)
              error("there is no field named %s", name);
            return v;
          }

        if (t_field_name
            && (t_field_name[0] == '\0'
                || (TYPE_CODE (type) == TYPE_CODE_UNION
                    && STREQ (t_field_name, "else"))))
          {
            struct type *field_type = TYPE_FIELD_TYPE (type, i);
            if (TYPE_CODE (field_type) == TYPE_CODE_UNION
                || TYPE_CODE (field_type) == TYPE_CODE_STRUCT)
              {
                /* Look for a match through the fields of an anonymous union,
                   or anonymous struct.  C++ provides anonymous unions.

                   In the GNU Chill implementation of variant record types,
                   each <alternative field> has an (anonymous) union type,
                   each member of the union represents a <variant alternative>.
                   Each <variant alternative> is represented as a struct,
                   with a member for each <variant field>.  */
                   
                value_ptr v;
                int new_offset = offset;

                /* This is pretty gross.  In G++, the offset in an anonymous
                   union is relative to the beginning of the enclosing struct.
                   In the GNU Chill implementation of variant records,
                   the bitpos is zero in an anonymous union field, so we
                   have to add the offset of the union here. */
                if (TYPE_CODE (field_type) == TYPE_CODE_STRUCT
                    || (TYPE_NFIELDS (field_type) > 0
                        && TYPE_FIELD_BITPOS (field_type, 0) == 0))
                  new_offset += TYPE_FIELD_BITPOS (type, i) / 8;

                v = search_struct_field (name, arg1, new_offset, field_type,
                                         looking_for_baseclass);
                if (v)
                  return v;
              }
          }
      }

  for (i = 0;  i < nbases;  i++)
    {
      value_ptr v;
      struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
      /* If we are looking for baseclasses, this is what we get when we
         hit them.  But it could happen that the base part's member name
         is not yet filled in.  */
      int found_baseclass = (looking_for_baseclass
                             && TYPE_BASECLASS_NAME (type, i) != NULL
                             && STREQ (name, TYPE_BASECLASS_NAME (type, i)));

      if (BASETYPE_VIA_VIRTUAL (type, i))
        {
          int boffset;
          value_ptr v2 = allocate_value (basetype);

          boffset = baseclass_offset (type, i,
                                      VALUE_CONTENTS (arg1) + offset,
                                      VALUE_ADDRESS (arg1)
                                        + VALUE_OFFSET (arg1) + offset);
          if (boffset == -1)
            error ("virtual baseclass botch");

          /* The virtual base class pointer might have been clobbered by the
             user program. Make sure that it still points to a valid memory
             location.  */

          boffset += offset;
          if (boffset < 0 || boffset >= TYPE_LENGTH (type))
            {
              CORE_ADDR base_addr;
        
              base_addr = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1) + boffset;
              if (target_read_memory (base_addr, VALUE_CONTENTS_RAW (v2),
                                      TYPE_LENGTH (basetype)) != 0)
                error ("virtual baseclass botch");
              VALUE_LVAL (v2) = lval_memory;
              VALUE_ADDRESS (v2) = base_addr;
            }
          else
            {
              VALUE_LVAL (v2) = VALUE_LVAL (arg1);
              VALUE_ADDRESS (v2) = VALUE_ADDRESS (arg1);
              VALUE_OFFSET (v2) = VALUE_OFFSET (arg1) + boffset;
              if (VALUE_LAZY (arg1))
                VALUE_LAZY (v2) = 1;
              else
                memcpy (VALUE_CONTENTS_RAW (v2),
                        VALUE_CONTENTS_RAW (arg1) + boffset,
                        TYPE_LENGTH (basetype));
            }

          if (found_baseclass)
            return v2;
          v = search_struct_field (name, v2, 0, TYPE_BASECLASS (type, i),
                                   looking_for_baseclass);
        }
      else if (found_baseclass)
        v = value_primitive_field (arg1, offset, i, type);
      else
        v = search_struct_field (name, arg1,
                                 offset + TYPE_BASECLASS_BITPOS (type, i) / 8,
                                 basetype, looking_for_baseclass);
      if (v) return v;
    }
  return NULL;
}


/* Return the offset (in bytes) of the virtual base of type BASETYPE
 * in an object pointed to by VALADDR (on the host), assumed to be of
 * type TYPE.  OFFSET is number of bytes beyond start of ARG to start
 * looking (in case VALADDR is the contents of an enclosing object).
 *
 * This routine recurses on the primary base of the derived class because
 * the virtual base entries of the primary base appear before the other
 * virtual base entries.
 *
 * If the virtual base is not found, a negative integer is returned.
 * The magnitude of the negative integer is the number of entries in
 * the virtual table to skip over (entries corresponding to various
 * ancestral classes in the chain of primary bases).
 *
 * Important: This assumes the HP / Taligent C++ runtime
 * conventions. Use baseclass_offset() instead to deal with g++
 * conventions.  */

void
find_rt_vbase_offset(type, basetype, valaddr, offset, boffset_p, skip_p)
  struct type * type;
  struct type * basetype;
  char * valaddr;
  int offset;
  int * boffset_p;
  int * skip_p;
{
  int boffset;           /* offset of virtual base */
  int index;             /* displacement to use in virtual table */
  int skip;
  
  value_ptr vp;      
  CORE_ADDR vtbl;      /* the virtual table pointer */
  struct type * pbc;   /* the primary base class */

  /* Look for the virtual base recursively in the primary base, first.
   * This is because the derived class object and its primary base
   * subobject share the primary virtual table.  */
  
  boffset = 0;
  pbc = TYPE_PRIMARY_BASE(type);
  if (pbc)
    {
      find_rt_vbase_offset (pbc, basetype, valaddr, offset, &boffset, &skip);
      if (skip < 0)
        {
          *boffset_p = boffset;
          *skip_p = -1;
          return;
        }
    }
  else
    skip = 0;


  /* Find the index of the virtual base according to HP/Taligent
     runtime spec. (Depth-first, left-to-right.)  */
  index = virtual_base_index_skip_primaries (basetype, type);

  if (index < 0) {
    *skip_p = skip + virtual_base_list_length_skip_primaries (type);
    *boffset_p = 0;
    return;
  }

  /* pai: FIXME -- 32x64 possible problem */ 
  /* First word (4 bytes) in object layout is the vtable pointer */
  vtbl = * (CORE_ADDR *) (valaddr + offset);

  /* Before the constructor is invoked, things are usually zero'd out. */ 
  if (vtbl == 0)
    error ("Couldn't find virtual table -- object may not be constructed yet.");


  /* Find virtual base's offset -- jump over entries for primary base
   * ancestors, then use the index computed above.  But also adjust by
   * HP_ACC_VBASE_START for the vtable slots before the start of the
   * virtual base entries.  Offset is negative -- virtual base entries
   * appear _before_ the address point of the virtual table. */
  
  /* pai: FIXME -- 32x64 problem, if word = 8 bytes, change multiplier 
     & use long type */ 

  /* epstein : FIXME -- added param for overlay section. May not be correct */
   vp = value_at (builtin_type_int, vtbl + 4 * (- skip - index - HP_ACC_VBASE_START), NULL);
  boffset = value_as_long (vp);
  *skip_p = -1;
  *boffset_p = boffset;
  return;
}


/* Helper function used by value_struct_elt to recurse through baseclasses.
   Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes,
   and search in it assuming it has (class) type TYPE.
   If found, return value, else if name matched and args not return (value)-1,
   else return NULL. */

static value_ptr
search_struct_method (name, arg1p, args, offset, static_memfuncp, type)
     char *name;
     register value_ptr *arg1p, *args;
     int offset, *static_memfuncp;
     register struct type *type;
{
  int i;
  value_ptr v;
  int name_matched = 0;
  char dem_opname[64];

  CHECK_TYPEDEF (type);
  for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
    {
      char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
      /* FIXME!  May need to check for ARM demangling here */
      if (strncmp(t_field_name, "__", 2)==0 ||
        strncmp(t_field_name, "op", 2)==0 ||
        strncmp(t_field_name, "type", 4)==0 )
        {
          if (cplus_demangle_opname(t_field_name, dem_opname, DMGL_ANSI))
            t_field_name = dem_opname;
          else if (cplus_demangle_opname(t_field_name, dem_opname, 0))
            t_field_name = dem_opname; 
        }
      if (t_field_name && STREQ (t_field_name, name))
        {
          int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
          struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
          name_matched = 1; 

          if (j > 0 && args == 0)
            error ("cannot resolve overloaded method `%s': no arguments supplied", name);
          while (j >= 0)
            {
              if (TYPE_FN_FIELD_STUB (f, j))
                check_stub_method (type, i, j);
              if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
                            TYPE_FN_FIELD_ARGS (f, j), args))
                {
                  if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
                    return value_virtual_fn_field (arg1p, f, j, type, offset);
                  if (TYPE_FN_FIELD_STATIC_P (f, j) && static_memfuncp)
                    *static_memfuncp = 1;
                  v = value_fn_field (arg1p, f, j, type, offset);
                  if (v != NULL) return v;
                }
              j--;
            }
        }
    }

  for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
    {
      int base_offset;

      if (BASETYPE_VIA_VIRTUAL (type, i))
        {
         if (TYPE_HAS_VTABLE (type))
            {
              /* HP aCC compiled type, search for virtual base offset
                 according to HP/Taligent runtime spec.  */
              int skip;
              find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
                                    VALUE_CONTENTS_ALL (*arg1p),
                                    offset + VALUE_EMBEDDED_OFFSET (*arg1p),
                                    &base_offset, &skip);
              if (skip >= 0)
                error ("Virtual base class offset not found in vtable");
            }
         else
           {
             struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
             char *base_valaddr;

             /* The virtual base class pointer might have been clobbered by the
                user program. Make sure that it still points to a valid memory
                location.  */

             if (offset < 0 || offset >= TYPE_LENGTH (type))
               {
                 base_valaddr = (char *) alloca (TYPE_LENGTH (baseclass));
                 if (target_read_memory (VALUE_ADDRESS (*arg1p)
                                         + VALUE_OFFSET (*arg1p) + offset,
                                         base_valaddr,
                                         TYPE_LENGTH (baseclass)) != 0)
                   error ("virtual baseclass botch");
               }
            else
               base_valaddr = VALUE_CONTENTS (*arg1p) + offset;

            base_offset =
               baseclass_offset (type, i, base_valaddr,
                                 VALUE_ADDRESS (*arg1p)
                                   + VALUE_OFFSET (*arg1p) + offset);
            if (base_offset == -1)
               error ("virtual baseclass botch");
           }
        }
      else
        {
          base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
        }
      v = search_struct_method (name, arg1p, args, base_offset + offset,
                                static_memfuncp, TYPE_BASECLASS (type, i));
      if (v == (value_ptr) -1)
        {
          name_matched = 1;
        }
      else if (v)
        {
/* FIXME-bothner:  Why is this commented out?  Why is it here?  */
/*        *arg1p = arg1_tmp;*/
          return v;
        }
    }
  if (name_matched) return (value_ptr) -1;
  else return NULL;
}

/* Given *ARGP, a value of type (pointer to a)* structure/union,
   extract the component named NAME from the ultimate target structure/union
   and return it as a value with its appropriate type.
   ERR is used in the error message if *ARGP's type is wrong.

   C++: ARGS is a list of argument types to aid in the selection of
   an appropriate method. Also, handle derived types.

   STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
   where the truthvalue of whether the function that was resolved was
   a static member function or not is stored.

   ERR is an error message to be printed in case the field is not found.  */

value_ptr
value_struct_elt (argp, args, name, static_memfuncp, err)
     register value_ptr *argp, *args;
     char *name;
     int *static_memfuncp;
     char *err;
{
  register struct type *t;
  value_ptr v;

  COERCE_ARRAY (*argp);

  t = check_typedef (VALUE_TYPE (*argp));

  /* Follow pointers until we get to a non-pointer.  */

  while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
    {
      *argp = value_ind (*argp);
      /* Don't coerce fn pointer to fn and then back again!  */
      if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
        COERCE_ARRAY (*argp);
      t = check_typedef (VALUE_TYPE (*argp));
    }

  if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
    error ("not implemented: member type in value_struct_elt");

  if (   TYPE_CODE (t) != TYPE_CODE_STRUCT
      && TYPE_CODE (t) != TYPE_CODE_UNION)
    error ("Attempt to extract a component of a value that is not a %s.", err);

  /* Assume it's not, unless we see that it is.  */
  if (static_memfuncp)
    *static_memfuncp =0;

  if (!args)
    {
      /* if there are no arguments ...do this...  */

      /* Try as a field first, because if we succeed, there
         is less work to be done.  */
      v = search_struct_field (name, *argp, 0, t, 0);
      if (v)
        return v;

      /* C++: If it was not found as a data field, then try to
         return it as a pointer to a method.  */

      if (destructor_name_p (name, t))
        error ("Cannot get value of destructor");

      v = search_struct_method (name, argp, args, 0, static_memfuncp, t);

      if (v == (value_ptr) -1)
        error ("Cannot take address of a method");
      else if (v == 0)
        {
          if (TYPE_NFN_FIELDS (t))
            error ("There is no member or method named %s.", name);
          else
            error ("There is no member named %s.", name);
        }
      return v;
    }

  if (destructor_name_p (name, t))
    {
      if (!args[1])
        {
          /* Destructors are a special case.  */
          int m_index, f_index;

          v = NULL;
          if (get_destructor_fn_field (t, &m_index, &f_index))
            {
              v = value_fn_field (NULL, TYPE_FN_FIELDLIST1 (t, m_index),
                                  f_index, NULL, 0);
            }
          if (v == NULL)
            error ("could not find destructor function named %s.", name);
          else
            return v;
        }
      else
        {
          error ("destructor should not have any argument");
        }
    }
  else
    v = search_struct_method (name, argp, args, 0, static_memfuncp, t);

  if (v == (value_ptr) -1)
    {
        error("Argument list of %s mismatch with component in the structure.", name);
    }
  else if (v == 0)
    {
      /* See if user tried to invoke data as function.  If so,
         hand it back.  If it's not callable (i.e., a pointer to function),
         gdb should give an error.  */
      v = search_struct_field (name, *argp, 0, t, 0);
    }

  if (!v)
    error ("Structure has no component named %s.", name);
  return v;
}

/* Search through the methods of an object (and its bases)
 * to find a specified method. Return the pointer to the
 * fn_field list of overloaded instances.
 * Helper function for value_find_oload_list.
 * ARGP is a pointer to a pointer to a value (the object)
 * METHOD is a string containing the method name
 * OFFSET is the offset within the value
 * STATIC_MEMFUNCP is set if the method is static
 * TYPE is the assumed type of the object
 * NUM_FNS is the number of overloaded instances
 * BASETYPE is set to the actual type of the subobject where the method is found
 * BOFFSET is the offset of the base subobject where the method is found */

struct fn_field *
find_method_list (argp, method, offset, static_memfuncp, type, num_fns, basetype, boffset)
  value_ptr *argp;
  char * method;
  int offset;
  int * static_memfuncp;
  struct type * type;
  int * num_fns;
  struct type ** basetype;
  int * boffset;
{
  int i;
  struct fn_field * f;
  CHECK_TYPEDEF (type);

  *num_fns = 0;

  /* First check in object itself */ 
  for (i = TYPE_NFN_FIELDS (type) -1; i >= 0; i--)
    {
      /* pai: FIXME What about operators and type conversions? */
      char * fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
      if (fn_field_name && STREQ (fn_field_name, method))
        {
          *num_fns = TYPE_FN_FIELDLIST_LENGTH (type, i);
          *basetype = type;
          *boffset = offset;
          return TYPE_FN_FIELDLIST1 (type, i);
        }
    }
  
  /* Not found in object, check in base subobjects */
  for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
    {
      int base_offset;
      if (BASETYPE_VIA_VIRTUAL (type, i))
        {
          if (TYPE_HAS_VTABLE (type))
            {
              /* HP aCC compiled type, search for virtual base offset
               * according to HP/Taligent runtime spec.  */
              int skip;
              find_rt_vbase_offset (type, TYPE_BASECLASS (type, i),
                                    VALUE_CONTENTS_ALL (*argp),
                                    offset + VALUE_EMBEDDED_OFFSET (*argp),
                                    &base_offset, &skip);
              if (skip >= 0)
                error ("Virtual base class offset not found in vtable");
            }
          else
            {
              /* probably g++ runtime model */ 
              base_offset = VALUE_OFFSET (*argp) + offset;
              base_offset =
                baseclass_offset (type, i,
                                  VALUE_CONTENTS (*argp) + base_offset,
                                  VALUE_ADDRESS (*argp) + base_offset);
              if (base_offset == -1)
                error ("virtual baseclass botch");
            }
        }
      else /* non-virtual base, simply use bit position from debug info */
        {
          base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
        }
      f = find_method_list (argp, method, base_offset + offset,
                            static_memfuncp, TYPE_BASECLASS (type, i), num_fns, basetype, boffset);
      if (f)
        return f;
    }
  return NULL;  
}

/* Return the list of overloaded methods of a specified name.
 * ARGP is a pointer to a pointer to a value (the object)
 * METHOD is the method name
 * OFFSET is the offset within the value contents
 * STATIC_MEMFUNCP is set if the method is static
 * NUM_FNS is the number of overloaded instances
 * BASETYPE is set to the type of the base subobject that defines the method
 * BOFFSET is the offset of the base subobject which defines the method */

struct fn_field *
value_find_oload_method_list (argp, method, offset, static_memfuncp, num_fns, basetype, boffset)
  value_ptr *argp;
  char * method;
  int offset;
  int * static_memfuncp;
  int * num_fns;
  struct type ** basetype;
  int * boffset;
{
  struct type * t;
  value_ptr v;

  t = check_typedef (VALUE_TYPE (*argp));

  /* code snarfed from value_struct_elt */ 
  while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF)
    {
      *argp = value_ind (*argp);
      /* Don't coerce fn pointer to fn and then back again!  */
      if (TYPE_CODE (VALUE_TYPE (*argp)) != TYPE_CODE_FUNC)
        COERCE_ARRAY (*argp);
      t = check_typedef (VALUE_TYPE (*argp));
    }
  
  if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
    error ("Not implemented: member type in value_find_oload_lis");
  
  if (   TYPE_CODE (t) != TYPE_CODE_STRUCT
         && TYPE_CODE (t) != TYPE_CODE_UNION)
    error ("Attempt to extract a component of a value that is not a struct or union");
  
  /* Assume it's not static, unless we see that it is.  */
  if (static_memfuncp)
    *static_memfuncp =0;

  return find_method_list (argp, method, 0, static_memfuncp, t, num_fns, basetype, boffset);
  
}

/* Given an array of argument types (ARGTYPES) (which includes an
   entry for "this" in the case of C++ methods), the number of
   arguments NARGS, the NAME of a function whether it's a method or
   not (METHOD), and the degree of laxness (LAX) in conforming to
   overload resolution rules in ANSI C++, find the best function that
   matches on the argument types according to the overload resolution
   rules.

   In the case of class methods, the parameter OBJ is an object value
   in which to search for overloaded methods.

   In the case of non-method functions, the parameter FSYM is a symbol
   corresponding to one of the overloaded functions.

   Return value is an integer: 0 -> good match, 10 -> debugger applied
   non-standard coercions, 100 -> incompatible.

   If a method is being searched for, VALP will hold the value.
   If a non-method is being searched for, SYMP will hold the symbol for it.

   If a method is being searched for, and it is a static method,
   then STATICP will point to a non-zero value.

   Note: This function does *not* check the value of
   overload_resolution.  Caller must check it to see whether overload
   resolution is permitted.
   */

int
find_overload_match (arg_types, nargs, name, method, lax, obj, fsym, valp, symp, staticp)
  struct type ** arg_types;
  int nargs;
  char * name;
  int method;
  int lax;
  value_ptr obj;
  struct symbol * fsym;
  value_ptr * valp;
  struct symbol ** symp;
  int * staticp;
{
  int nparms;
  struct type ** parm_types;
  int champ_nparms = 0;
  
  short oload_champ = -1;          /* Index of best overloaded function */
  short oload_ambiguous = 0;       /* Current ambiguity state for overload resolution */
                                   /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs */
  short oload_ambig_champ = -1;    /* 2nd contender for best match */ 
  short oload_non_standard = 0;    /* did we have to use non-standard conversions? */ 
  short oload_incompatible = 0;    /* are args supplied incompatible with any function? */
  
  struct badness_vector * bv;      /* A measure of how good an overloaded instance is */ 
  struct badness_vector * oload_champ_bv = NULL; /* The measure for the current best match */ 
  
  value_ptr temp = obj;
  struct fn_field * fns_ptr = NULL;   /* For methods, the list of overloaded methods */ 
  struct symbol ** oload_syms = NULL; /* For non-methods, the list of overloaded function symbols */
  int num_fns = 0;                    /* Number of overloaded instances being considered */ 
  struct type * basetype = NULL;   
  int boffset;
  register int jj;
  register int ix;

  char * obj_type_name = NULL;
  char * func_name = NULL;

  /* Get the list of overloaded methods or functions */
  if (method)
    {
      obj_type_name = TYPE_NAME (VALUE_TYPE (obj));
      /* Hack: evaluate_subexp_standard often passes in a pointer
         value rather than the object itself, so try again */
      if ((!obj_type_name || !*obj_type_name) &&
          (TYPE_CODE (VALUE_TYPE (obj)) == TYPE_CODE_PTR))
        obj_type_name = TYPE_NAME (TYPE_TARGET_TYPE (VALUE_TYPE (obj)));

      fns_ptr = value_find_oload_method_list (&temp, name, 0,
                                              staticp,
                                              &num_fns,
                                              &basetype, &boffset);
      if (!fns_ptr || !num_fns)
        error ("Couldn't find method %s%s%s",
               obj_type_name,
               (obj_type_name && *obj_type_name) ? "::" : "",
               name);
    }
  else
    {
      int i = -1;
      func_name = cplus_demangle (SYMBOL_NAME (fsym), DMGL_NO_OPTS);

      oload_syms = make_symbol_overload_list (fsym);
      while (oload_syms[++i])
        num_fns++;
      if (!num_fns)
        error ("Couldn't find function %s", func_name);
    }
  
  oload_champ_bv = NULL;

  /* Consider each candidate in turn */ 
  for (ix = 0; ix < num_fns; ix++)
    {
      int jj;

      /* Number of parameters for current candidate */ 
      nparms = method ? TYPE_NFIELDS (fns_ptr[ix].type)
                      : TYPE_NFIELDS (SYMBOL_TYPE (oload_syms[ix]));

      /* Prepare array of parameter types */ 
      parm_types = (struct type **) xmalloc (nparms * (sizeof (struct type *)));
      for (jj = 0; jj < nparms; jj++)
        parm_types[jj] = method ? TYPE_FIELD_TYPE (fns_ptr[ix].type, jj)
                                : TYPE_FIELD_TYPE (SYMBOL_TYPE (oload_syms[ix]), jj);

      /* Compare parameter types to supplied argument types */
      bv = rank_function (parm_types, nparms, arg_types, nargs);
      
      if (!oload_champ_bv)
        {
          oload_champ_bv = bv;
          oload_champ = 0;
          champ_nparms = nparms;
        }
      else
        /* See whether current candidate is better or worse than previous best */ 
        switch (compare_badness (bv, oload_champ_bv))
          {
            case 0:
              oload_ambiguous = 1;    /* top two contenders are equally good */ 
              oload_ambig_champ = ix;
              break;
            case 1:
              oload_ambiguous = 2;    /* incomparable top contenders */ 
              oload_ambig_champ = ix;
              break;
            case 2:
              oload_champ_bv = bv;    /* new champion, record details */ 
              oload_ambiguous = 0;
              oload_champ = ix;
              oload_ambig_champ = -1;
              champ_nparms = nparms;
              break;
            case 3:
            default:
              break;
          }
      free (parm_types);
#ifdef DEBUG_OLOAD
      if (method)
        printf("Overloaded method instance %s, # of parms %d\n", fns_ptr[ix].physname, nparms);
      else
        printf("Overloaded function instance %s # of parms %d\n", SYMBOL_DEMANGLED_NAME(oload_syms[ix]),nparms); 
      for (jj = 0; jj <= nargs; jj++)
        printf("...Badness @ %d : %d\n", jj, bv->rank[jj]);
      printf("Overload resolution champion is %d, ambiguous? %d\n", oload_champ, oload_ambiguous);
#endif
    } /* end loop over all candidates */ 

  if (oload_ambiguous)
    {
      if (method)
        error ("Cannot resolve overloaded method %s%s%s to unique instance; disambiguate by specifying function signature",
               obj_type_name,
               (obj_type_name && *obj_type_name) ? "::" : "",
               name);
      else
        error ("Cannot resolve overloaded function %s to unique instance; disambiguate by specifying function signature",
               func_name);
    }

  /* Check how bad the best match is */ 
  for (ix = 1; ix <= nargs; ix++)
    {
      switch (oload_champ_bv->rank[ix])
        {
          case 10:
            oload_non_standard = 1;  /* non-standard type conversions needed */ 
            break;
          case 100:
            oload_incompatible = 1;  /* truly mismatched types */ 
            break;
        }
    }
  if (oload_incompatible)
    {
      if (method)
        error ("Cannot resolve method %s%s%s to any overloaded instance",
               obj_type_name,
               (obj_type_name && *obj_type_name) ? "::" : "",
               name);
      else
        error ("Cannot resolve function %s to any overloaded instance",
               func_name);
    }
  else if (oload_non_standard)
    {
      if (method)
        warning ("Using non-standard conversion to match method %s%s%s to supplied arguments",
                 obj_type_name,
                 (obj_type_name && *obj_type_name) ? "::" : "",
                 name);
      else
        warning ("Using non-standard conversion to match function %s to supplied arguments",
                 func_name);
    }

  if (method)
    {
      if (TYPE_FN_FIELD_VIRTUAL_P (fns_ptr, oload_champ))
        *valp = value_virtual_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
      else
        *valp = value_fn_field (&temp, fns_ptr, oload_champ, basetype, boffset);
    }
  else
    {
      *symp = oload_syms[oload_champ];
      free (func_name);
    }

  return oload_incompatible ? 100 : (oload_non_standard ? 10 : 0);
}

/* C++: return 1 is NAME is a legitimate name for the destructor
   of type TYPE.  If TYPE does not have a destructor, or
   if NAME is inappropriate for TYPE, an error is signaled.  */
int
destructor_name_p (name, type)
     const char *name;
     const struct type *type;
{
  /* destructors are a special case.  */

  if (name[0] == '~')
    {
      char *dname = type_name_no_tag (type);
      char *cp = strchr (dname, '<');
      unsigned int len;

      /* Do not compare the template part for template classes.  */
      if (cp == NULL)
        len = strlen (dname);
      else
        len = cp - dname;
      if (strlen (name + 1) != len || !STREQN (dname, name + 1, len))
        error ("name of destructor must equal name of class");
      else
        return 1;
    }
  return 0;
}

/* Helper function for check_field: Given TYPE, a structure/union,
   return 1 if the component named NAME from the ultimate
   target structure/union is defined, otherwise, return 0. */

static int
check_field_in (type, name)
     register struct type *type;
     const char *name;
{
  register int i;

  for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--)
    {
      char *t_field_name = TYPE_FIELD_NAME (type, i);
      if (t_field_name && STREQ (t_field_name, name))
        return 1;
    }

  /* C++: If it was not found as a data field, then try to
     return it as a pointer to a method.  */

  /* Destructors are a special case.  */
  if (destructor_name_p (name, type))
    {
      int m_index, f_index;

      return get_destructor_fn_field (type, &m_index, &f_index);
    }

  for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i)
    {
      if (STREQ (TYPE_FN_FIELDLIST_NAME (type, i), name))
        return 1;
    }

  for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
    if (check_field_in (TYPE_BASECLASS (type, i), name))
      return 1;
      
  return 0;
}


/* C++: Given ARG1, a value of type (pointer to a)* structure/union,
   return 1 if the component named NAME from the ultimate
   target structure/union is defined, otherwise, return 0.  */

int
check_field (arg1, name)
     register value_ptr arg1;
     const char *name;
{
  register struct type *t;

  COERCE_ARRAY (arg1);

  t = VALUE_TYPE (arg1);

  /* Follow pointers until we get to a non-pointer.  */

  for (;;)
    {
      CHECK_TYPEDEF (t);
      if (TYPE_CODE (t) != TYPE_CODE_PTR && TYPE_CODE (t) != TYPE_CODE_REF)
        break;
      t = TYPE_TARGET_TYPE (t);
    }

  if (TYPE_CODE (t) == TYPE_CODE_MEMBER)
    error ("not implemented: member type in check_field");

  if (   TYPE_CODE (t) != TYPE_CODE_STRUCT
      && TYPE_CODE (t) != TYPE_CODE_UNION)
    error ("Internal error: `this' is not an aggregate");

  return check_field_in (t, name);
}

/* C++: Given an aggregate type CURTYPE, and a member name NAME,
   return the address of this member as a "pointer to member"
   type.  If INTYPE is non-null, then it will be the type
   of the member we are looking for.  This will help us resolve
   "pointers to member functions".  This function is used
   to resolve user expressions of the form "DOMAIN::NAME".  */

value_ptr
value_struct_elt_for_reference (domain, offset, curtype, name, intype)
     struct type *domain, *curtype, *intype;
     int offset;
     char *name;
{
  register struct type *t = curtype;
  register int i;
  value_ptr v;

  if (   TYPE_CODE (t) != TYPE_CODE_STRUCT
      && TYPE_CODE (t) != TYPE_CODE_UNION)
    error ("Internal error: non-aggregate type to value_struct_elt_for_reference");

  for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--)
    {
      char *t_field_name = TYPE_FIELD_NAME (t, i);
      
      if (t_field_name && STREQ (t_field_name, name))
        {
          if (TYPE_FIELD_STATIC (t, i))
            {
              v = value_static_field (t, i);
              if (v == NULL)
                error ("Internal error: could not find static variable %s",
                       name);
              return v;
            }
          if (TYPE_FIELD_PACKED (t, i))
            error ("pointers to bitfield members not allowed");
          
          return value_from_longest
            (lookup_reference_type (lookup_member_type (TYPE_FIELD_TYPE (t, i),
                                                        domain)),
             offset + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3));
        }
    }

  /* C++: If it was not found as a data field, then try to
     return it as a pointer to a method.  */

  /* Destructors are a special case.  */
  if (destructor_name_p (name, t))
    {
      error ("member pointers to destructors not implemented yet");
    }

  /* Perform all necessary dereferencing.  */
  while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR)
    intype = TYPE_TARGET_TYPE (intype);

  for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
    {
      char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
      char dem_opname[64];

      if (strncmp(t_field_name, "__", 2)==0 ||
        strncmp(t_field_name, "op", 2)==0 ||
        strncmp(t_field_name, "type", 4)==0 )
        {
          if (cplus_demangle_opname(t_field_name, dem_opname, DMGL_ANSI))
            t_field_name = dem_opname;
          else if (cplus_demangle_opname(t_field_name, dem_opname, 0))
            t_field_name = dem_opname; 
        }
      if (t_field_name && STREQ (t_field_name, name))
        {
          int j = TYPE_FN_FIELDLIST_LENGTH (t, i);
          struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
          
          if (intype == 0 && j > 1)
            error ("non-unique member `%s' requires type instantiation", name);
          if (intype)
            {
              while (j--)
                if (TYPE_FN_FIELD_TYPE (f, j) == intype)
                  break;
              if (j < 0)
                error ("no member function matches that type instantiation");
            }
          else
            j = 0;
          
          if (TYPE_FN_FIELD_STUB (f, j))
            check_stub_method (t, i, j);
          if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
            {
              return value_from_longest
                (lookup_reference_type
                 (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
                                      domain)),
                 (LONGEST) METHOD_PTR_FROM_VOFFSET (TYPE_FN_FIELD_VOFFSET (f, j)));
            }
          else
            {
              struct symbol *s = lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
                                                0, VAR_NAMESPACE, 0, NULL);
              if (s == NULL)
                {
                  v = 0;
                }
              else
                {
                  v = read_var_value (s, 0);
#if 0
                  VALUE_TYPE (v) = lookup_reference_type
                    (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j),
                                         domain));
#endif
                }
              return v;
            }
        }
    }
  for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
    {
      value_ptr v;
      int base_offset;

      if (BASETYPE_VIA_VIRTUAL (t, i))
        base_offset = 0;
      else
        base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
      v = value_struct_elt_for_reference (domain,
                                          offset + base_offset,
                                          TYPE_BASECLASS (t, i),
                                          name,
                                          intype);
      if (v)
        return v;
    }
  return 0;
}


/* Find the real run-time type of a value using RTTI.
 * V is a pointer to the value.
 * A pointer to the struct type entry of the run-time type
 * is returneed.
 * FULL is a flag that is set only if the value V includes
 * the entire contents of an object of the RTTI type.
 * TOP is the offset to the top of the enclosing object of
 * the real run-time type.  This offset may be for the embedded
 * object, or for the enclosing object of V.
 * USING_ENC is the flag that distinguishes the two cases.
 * If it is 1, then the offset is for the enclosing object,
 * otherwise for the embedded object.
 * 
 * This currently works only for RTTI information generated
 * by the HP ANSI C++ compiler (aCC).  g++ today (1997-06-10)
 * does not appear to support RTTI. This function returns a
 * NULL value for objects in the g++ runtime model. */

struct type *
value_rtti_type (v, full, top, using_enc)
  value_ptr v;
  int * full;
  int * top;
  int * using_enc;
{
  struct type * known_type;
  struct type * rtti_type;
  CORE_ADDR coreptr;
  value_ptr vp;
  int using_enclosing = 0;
  long top_offset = 0;
  char rtti_type_name[256];

  if (full)
    *full = 0;
  if (top)
    *top = -1;
  if (using_enc)
    *using_enc = 0;

  /* Get declared type */ 
  known_type = VALUE_TYPE (v);
  CHECK_TYPEDEF (known_type);
  /* RTTI works only or class objects */ 
  if (TYPE_CODE (known_type) != TYPE_CODE_CLASS)
    return NULL;

  /* If neither the declared type nor the enclosing type of the
   * value structure has a HP ANSI C++ style virtual table,
   * we can't do anything. */
  if (!TYPE_HAS_VTABLE (known_type))
    {
      known_type = VALUE_ENCLOSING_TYPE (v);
      CHECK_TYPEDEF (known_type);
      if ((TYPE_CODE (known_type) != TYPE_CODE_CLASS) ||
          !TYPE_HAS_VTABLE (known_type))
        return NULL; /* No RTTI, or not HP-compiled types */
      CHECK_TYPEDEF (known_type);
      using_enclosing = 1;
    }

  if (using_enclosing && using_enc)
    *using_enc = 1;

  /* First get the virtual table address */
  coreptr = * (CORE_ADDR *) ((VALUE_CONTENTS_ALL (v))
                             + VALUE_OFFSET (v) 
                             + (using_enclosing ? 0 : VALUE_EMBEDDED_OFFSET (v)));
  if (coreptr == 0)
    return NULL; /* return silently -- maybe called on gdb-generated value */

  /* Fetch the top offset of the object */ 
  /* FIXME possible 32x64 problem with pointer size & arithmetic */
  vp = value_at (builtin_type_int, 
                 coreptr + 4 * HP_ACC_TOP_OFFSET_OFFSET, 
                 VALUE_BFD_SECTION (v));
  top_offset = value_as_long (vp);
  if (top)
    *top = top_offset;

  /* Fetch the typeinfo pointer */
  /* FIXME possible 32x64 problem with pointer size & arithmetic */
  vp = value_at (builtin_type_int, coreptr + 4 * HP_ACC_TYPEINFO_OFFSET, VALUE_BFD_SECTION (v));
  /* Indirect through the typeinfo pointer and retrieve the pointer
   * to the string name */
  coreptr = * (CORE_ADDR *) (VALUE_CONTENTS (vp));
  if (!coreptr)
    error ("Retrieved null typeinfo pointer in trying to determine run-time type");
  vp = value_at (builtin_type_int, coreptr + 4, VALUE_BFD_SECTION (v));  /* 4 -> offset of name field */
                                                  /* FIXME possible 32x64 problem */

  coreptr = * (CORE_ADDR *) (VALUE_CONTENTS (vp));

  read_memory_string (coreptr, rtti_type_name, 256);

  if (strlen (rtti_type_name) == 0)
    error ("Retrieved null type name from typeinfo");
  
  /* search for type */
  rtti_type = lookup_typename (rtti_type_name, (struct block *) 0, 1);
  
  if (!rtti_type)
    error ("Could not find run-time type: invalid type name %s in typeinfo??", rtti_type_name);
  CHECK_TYPEDEF (rtti_type);

#if 0 /* debugging*/
  printf("RTTI type name %s, tag %s, full? %d\n", TYPE_NAME (rtti_type), TYPE_TAG_NAME (rtti_type), full ? *full : -1); 
#endif

  /* Check whether we have the entire object */
  if (full /* Non-null pointer passed */ 

      &&
           /* Either we checked on the whole object in hand and found the
              top offset to be zero */
      (((top_offset == 0) &&         
       using_enclosing &&     
       TYPE_LENGTH (known_type) == TYPE_LENGTH (rtti_type))
      ||
           /* Or we checked on the embedded object and top offset was the
              same as the embedded offset */
      ((top_offset == VALUE_EMBEDDED_OFFSET (v)) &&
       !using_enclosing &&
       TYPE_LENGTH (VALUE_ENCLOSING_TYPE (v)) == TYPE_LENGTH (rtti_type))))
    
    *full = 1;
  
  return rtti_type;
}

/* Given a pointer value V, find the real (RTTI) type
   of the object it points to.
   Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
   and refer to the values computed for the object pointed to. */

struct type *
value_rtti_target_type (v, full, top, using_enc)
  value_ptr v;
  int * full;
  int * top;
  int * using_enc;
{
  value_ptr target;

  target = value_ind (v);

  return value_rtti_type (target, full, top, using_enc);
}

/* Given a value pointed to by ARGP, check its real run-time type, and
   if that is different from the enclosing type, create a new value
   using the real run-time type as the enclosing type (and of the same
   type as ARGP) and return it, with the embedded offset adjusted to
   be the correct offset to the enclosed object
   RTYPE is the type, and XFULL, XTOP, and XUSING_ENC are the other
   parameters, computed by value_rtti_type(). If these are available,
   they can be supplied and a second call to value_rtti_type() is avoided.
   (Pass RTYPE == NULL if they're not available */

value_ptr
value_full_object (argp, rtype, xfull, xtop, xusing_enc)
  value_ptr argp;
  struct type * rtype;
  int xfull;
  int xtop;
  int xusing_enc;
  
{
  struct type * real_type;
  int full = 0;
  int top = -1;
  int using_enc = 0;
  value_ptr new_val;

  if (rtype)
    {
      real_type = rtype;
      full = xfull;
      top = xtop;
      using_enc = xusing_enc;
    }
  else
    real_type = value_rtti_type (argp, &full, &top, &using_enc);

  /* If no RTTI data, or if object is already complete, do nothing */
  if (!real_type || real_type == VALUE_ENCLOSING_TYPE (argp))
    return argp;

  /* If we have the full object, but for some reason the enclosing
     type is wrong, set it */ /* pai: FIXME -- sounds iffy */
  if (full)
    {
      VALUE_ENCLOSING_TYPE (argp) = real_type;
      return argp;
    }

  /* Check if object is in memory */
  if (VALUE_LVAL (argp) != lval_memory)
    {
      warning ("Couldn't retrieve complete object of RTTI type %s; object may be in register(s).", TYPE_NAME (real_type));
      
      return argp;
    }
  
  /* All other cases -- retrieve the complete object */
  /* Go back by the computed top_offset from the beginning of the object,
     adjusting for the embedded offset of argp if that's what value_rtti_type
     used for its computation. */
  new_val = value_at_lazy (real_type, VALUE_ADDRESS (argp) - top +
                           (using_enc ? 0 : VALUE_EMBEDDED_OFFSET (argp)), 
                           VALUE_BFD_SECTION (argp));
  VALUE_TYPE (new_val) = VALUE_TYPE (argp);
  VALUE_EMBEDDED_OFFSET (new_val) = using_enc ? top + VALUE_EMBEDDED_OFFSET (argp) : top;
  return new_val;
}




/* C++: return the value of the class instance variable, if one exists.
   Flag COMPLAIN signals an error if the request is made in an
   inappropriate context.  */

value_ptr
value_of_this (complain)
     int complain;
{
  struct symbol *func, *sym;
  struct block *b;
  int i;
  static const char funny_this[] = "this";
  value_ptr this;

  if (selected_frame == 0)
    {
      if (complain)
        error ("no frame selected");
      else return 0;
    }

  func = get_frame_function (selected_frame);
  if (!func)
    {
      if (complain)
        error ("no `this' in nameless context");
      else return 0;
    }

  b = SYMBOL_BLOCK_VALUE (func);
  i = BLOCK_NSYMS (b);
  if (i <= 0)
    {
      if (complain)
        error ("no args, no `this'");
      else return 0;
    }

  /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER
     symbol instead of the LOC_ARG one (if both exist).  */
  sym = lookup_block_symbol (b, funny_this, VAR_NAMESPACE);
  if (sym == NULL)
    {
      if (complain)
        error ("current stack frame not in method");
      else
        return NULL;
    }

  this = read_var_value (sym, selected_frame);
  if (this == 0 && complain)
    error ("`this' argument at unknown address");
  return this;
}

/* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH elements
   long, starting at LOWBOUND.  The result has the same lower bound as
   the original ARRAY.  */

value_ptr
value_slice (array, lowbound, length)
     value_ptr array;
     int lowbound, length;
{
  struct type *slice_range_type, *slice_type, *range_type;
  LONGEST lowerbound, upperbound, offset;
  value_ptr slice;
  struct type *array_type;
  array_type = check_typedef (VALUE_TYPE (array));
  COERCE_VARYING_ARRAY (array, array_type);
  if (TYPE_CODE (array_type) != TYPE_CODE_ARRAY
      && TYPE_CODE (array_type) != TYPE_CODE_STRING
      && TYPE_CODE (array_type) != TYPE_CODE_BITSTRING)
    error ("cannot take slice of non-array");
  range_type = TYPE_INDEX_TYPE (array_type);
  if (get_discrete_bounds (range_type, &lowerbound, &upperbound) < 0)
    error ("slice from bad array or bitstring");
  if (lowbound < lowerbound || length < 0
      || lowbound + length - 1 > upperbound
      /* Chill allows zero-length strings but not arrays. */
      || (current_language->la_language == language_chill
          && length == 0 && TYPE_CODE (array_type) == TYPE_CODE_ARRAY))
    error ("slice out of range");
  /* FIXME-type-allocation: need a way to free this type when we are
     done with it.  */
  slice_range_type = create_range_type ((struct type*) NULL,
                                        TYPE_TARGET_TYPE (range_type),
                                        lowbound, lowbound + length - 1);
  if (TYPE_CODE (array_type) == TYPE_CODE_BITSTRING)
    {
      int i;
      slice_type = create_set_type ((struct type*) NULL, slice_range_type);
      TYPE_CODE (slice_type) = TYPE_CODE_BITSTRING;
      slice = value_zero (slice_type, not_lval);
      for (i = 0; i < length; i++)
        {
          int element = value_bit_index (array_type,
                                         VALUE_CONTENTS (array),
                                         lowbound + i);
          if (element < 0)
            error ("internal error accessing bitstring");
          else if (element > 0)
            {
              int j = i % TARGET_CHAR_BIT;
              if (BITS_BIG_ENDIAN)
                j = TARGET_CHAR_BIT - 1 - j;
              VALUE_CONTENTS_RAW (slice)[i / TARGET_CHAR_BIT] |= (1 << j);
            }
        }
      /* We should set the address, bitssize, and bitspos, so the clice
         can be used on the LHS, but that may require extensions to
         value_assign.  For now, just leave as a non_lval.  FIXME.  */
    }
  else
    {
      struct type *element_type = TYPE_TARGET_TYPE (array_type);
      offset
        = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
      slice_type = create_array_type ((struct type*) NULL, element_type,
                                      slice_range_type);
      TYPE_CODE (slice_type) = TYPE_CODE (array_type);
      slice = allocate_value (slice_type);
      if (VALUE_LAZY (array))
        VALUE_LAZY (slice) = 1;
      else
        memcpy (VALUE_CONTENTS (slice), VALUE_CONTENTS (array) + offset,
                TYPE_LENGTH (slice_type));
      if (VALUE_LVAL (array) == lval_internalvar)
        VALUE_LVAL (slice) = lval_internalvar_component;
      else
        VALUE_LVAL (slice) = VALUE_LVAL (array);
      VALUE_ADDRESS (slice) = VALUE_ADDRESS (array);
      VALUE_OFFSET (slice) = VALUE_OFFSET (array) + offset;
    }
  return slice;
}

/* Assuming chill_varying_type (VARRAY) is true, return an equivalent
   value as a fixed-length array. */

value_ptr
varying_to_slice (varray)
     value_ptr varray;
{
  struct type *vtype = check_typedef (VALUE_TYPE (varray));
  LONGEST length = unpack_long (TYPE_FIELD_TYPE (vtype, 0),
                                VALUE_CONTENTS (varray)
                                + TYPE_FIELD_BITPOS (vtype, 0) / 8);
  return value_slice (value_primitive_field (varray, 0, 1, vtype), 0, length);
}

/* Create a value for a FORTRAN complex number.  Currently most of 
   the time values are coerced to COMPLEX*16 (i.e. a complex number 
   composed of 2 doubles.  This really should be a smarter routine 
   that figures out precision inteligently as opposed to assuming 
   doubles. FIXME: fmb */ 

value_ptr
value_literal_complex (arg1, arg2, type)
     value_ptr arg1;
     value_ptr arg2;
     struct type *type;
{
  register value_ptr val;
  struct type *real_type = TYPE_TARGET_TYPE (type);

  val = allocate_value (type);
  arg1 = value_cast (real_type, arg1);
  arg2 = value_cast (real_type, arg2);

  memcpy (VALUE_CONTENTS_RAW (val),
          VALUE_CONTENTS (arg1), TYPE_LENGTH (real_type));
  memcpy (VALUE_CONTENTS_RAW (val) + TYPE_LENGTH (real_type),
          VALUE_CONTENTS (arg2), TYPE_LENGTH (real_type));
  return val;
}

/* Cast a value into the appropriate complex data type. */

static value_ptr
cast_into_complex (type, val)
     struct type *type;
     register value_ptr val;
{
  struct type *real_type = TYPE_TARGET_TYPE (type);
  if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_COMPLEX)
    {
      struct type *val_real_type = TYPE_TARGET_TYPE (VALUE_TYPE (val));
      value_ptr re_val = allocate_value (val_real_type);
      value_ptr im_val = allocate_value (val_real_type);

      memcpy (VALUE_CONTENTS_RAW (re_val),
              VALUE_CONTENTS (val), TYPE_LENGTH (val_real_type));
      memcpy (VALUE_CONTENTS_RAW (im_val),
              VALUE_CONTENTS (val) + TYPE_LENGTH (val_real_type),
               TYPE_LENGTH (val_real_type));

      return value_literal_complex (re_val, im_val, type);
    }
  else if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FLT
           || TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_INT)
    return value_literal_complex (val, value_zero (real_type, not_lval), type);
  else
    error ("cannot cast non-number to complex");
}

void
_initialize_valops ()
{
#if 0
  add_show_from_set
    (add_set_cmd ("abandon", class_support, var_boolean, (char *)&auto_abandon,
                  "Set automatic abandonment of expressions upon failure.",
                  &setlist),
     &showlist);
#endif

  add_show_from_set
    (add_set_cmd ("overload-resolution", class_support, var_boolean, (char *)&overload_resolution,
                  "Set overload resolution in evaluating C++ functions.",
                  &setlist),
     &showlist);
  overload_resolution = 1;

}