1593 lines
45 KiB
C
1593 lines
45 KiB
C
/* Low level packing and unpacking of values for GDB, the GNU Debugger.
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Copyright 1986, 1987, 1989, 1991 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
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#include "defs.h"
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#include <string.h>
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#include "symtab.h"
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#include "gdbtypes.h"
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#include "value.h"
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#include "gdbcore.h"
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#include "frame.h"
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#include "command.h"
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#include "gdbcmd.h"
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#include "target.h"
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#include "demangle.h"
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/* Local function prototypes. */
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static value
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value_headof PARAMS ((value, struct type *, struct type *));
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static void
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show_values PARAMS ((char *, int));
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static void
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show_convenience PARAMS ((char *, int));
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/* The value-history records all the values printed
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by print commands during this session. Each chunk
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records 60 consecutive values. The first chunk on
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the chain records the most recent values.
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The total number of values is in value_history_count. */
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#define VALUE_HISTORY_CHUNK 60
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struct value_history_chunk
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{
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struct value_history_chunk *next;
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value values[VALUE_HISTORY_CHUNK];
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};
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/* Chain of chunks now in use. */
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static struct value_history_chunk *value_history_chain;
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static int value_history_count; /* Abs number of last entry stored */
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/* List of all value objects currently allocated
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(except for those released by calls to release_value)
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This is so they can be freed after each command. */
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static value all_values;
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/* Allocate a value that has the correct length for type TYPE. */
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value
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allocate_value (type)
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struct type *type;
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{
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register value val;
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check_stub_type (type);
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val = (value) xmalloc (sizeof (struct value) + TYPE_LENGTH (type));
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VALUE_NEXT (val) = all_values;
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all_values = val;
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VALUE_TYPE (val) = type;
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VALUE_LVAL (val) = not_lval;
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VALUE_ADDRESS (val) = 0;
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VALUE_FRAME (val) = 0;
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VALUE_OFFSET (val) = 0;
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VALUE_BITPOS (val) = 0;
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VALUE_BITSIZE (val) = 0;
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VALUE_REPEATED (val) = 0;
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VALUE_REPETITIONS (val) = 0;
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VALUE_REGNO (val) = -1;
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VALUE_LAZY (val) = 0;
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VALUE_OPTIMIZED_OUT (val) = 0;
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return val;
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}
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/* Allocate a value that has the correct length
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for COUNT repetitions type TYPE. */
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value
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allocate_repeat_value (type, count)
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struct type *type;
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int count;
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{
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register value val;
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val = (value) xmalloc (sizeof (struct value) + TYPE_LENGTH (type) * count);
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VALUE_NEXT (val) = all_values;
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all_values = val;
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VALUE_TYPE (val) = type;
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VALUE_LVAL (val) = not_lval;
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VALUE_ADDRESS (val) = 0;
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VALUE_FRAME (val) = 0;
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VALUE_OFFSET (val) = 0;
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VALUE_BITPOS (val) = 0;
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VALUE_BITSIZE (val) = 0;
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VALUE_REPEATED (val) = 1;
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VALUE_REPETITIONS (val) = count;
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VALUE_REGNO (val) = -1;
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VALUE_LAZY (val) = 0;
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VALUE_OPTIMIZED_OUT (val) = 0;
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return val;
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}
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/* Return a mark in the value chain. All values allocated after the
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mark is obtained (except for those released) are subject to being freed
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if a subsequent value_free_to_mark is passed the mark. */
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value
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value_mark ()
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{
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return all_values;
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}
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/* Free all values allocated since MARK was obtained by value_mark
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(except for those released). */
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void
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value_free_to_mark (mark)
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value mark;
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{
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value val, next;
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for (val = all_values; val && val != mark; val = next)
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{
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next = VALUE_NEXT (val);
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value_free (val);
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}
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all_values = val;
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}
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/* Free all the values that have been allocated (except for those released).
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Called after each command, successful or not. */
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void
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free_all_values ()
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{
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register value val, next;
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for (val = all_values; val; val = next)
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{
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next = VALUE_NEXT (val);
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value_free (val);
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}
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all_values = 0;
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}
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/* Remove VAL from the chain all_values
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so it will not be freed automatically. */
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void
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release_value (val)
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register value val;
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{
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register value v;
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if (all_values == val)
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{
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all_values = val->next;
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return;
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}
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for (v = all_values; v; v = v->next)
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{
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if (v->next == val)
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{
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v->next = val->next;
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break;
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}
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}
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}
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/* Return a copy of the value ARG.
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It contains the same contents, for same memory address,
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but it's a different block of storage. */
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value
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value_copy (arg)
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value arg;
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{
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register value val;
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register struct type *type = VALUE_TYPE (arg);
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if (VALUE_REPEATED (arg))
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val = allocate_repeat_value (type, VALUE_REPETITIONS (arg));
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else
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val = allocate_value (type);
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VALUE_LVAL (val) = VALUE_LVAL (arg);
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VALUE_ADDRESS (val) = VALUE_ADDRESS (arg);
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VALUE_OFFSET (val) = VALUE_OFFSET (arg);
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VALUE_BITPOS (val) = VALUE_BITPOS (arg);
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VALUE_BITSIZE (val) = VALUE_BITSIZE (arg);
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VALUE_REGNO (val) = VALUE_REGNO (arg);
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VALUE_LAZY (val) = VALUE_LAZY (arg);
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if (!VALUE_LAZY (val))
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{
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memcpy (VALUE_CONTENTS_RAW (val), VALUE_CONTENTS_RAW (arg),
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TYPE_LENGTH (VALUE_TYPE (arg))
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* (VALUE_REPEATED (arg) ? VALUE_REPETITIONS (arg) : 1));
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}
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return val;
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}
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/* Access to the value history. */
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/* Record a new value in the value history.
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Returns the absolute history index of the entry.
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Result of -1 indicates the value was not saved; otherwise it is the
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value history index of this new item. */
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int
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record_latest_value (val)
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value val;
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{
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int i;
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/* Check error now if about to store an invalid float. We return -1
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to the caller, but allow them to continue, e.g. to print it as "Nan". */
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if (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_FLT)
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{
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unpack_double (VALUE_TYPE (val), VALUE_CONTENTS (val), &i);
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if (i) return -1; /* Indicate value not saved in history */
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}
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/* Here we treat value_history_count as origin-zero
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and applying to the value being stored now. */
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i = value_history_count % VALUE_HISTORY_CHUNK;
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if (i == 0)
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{
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register struct value_history_chunk *new
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= (struct value_history_chunk *)
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xmalloc (sizeof (struct value_history_chunk));
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memset (new->values, 0, sizeof new->values);
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new->next = value_history_chain;
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value_history_chain = new;
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}
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value_history_chain->values[i] = val;
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release_value (val);
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/* Now we regard value_history_count as origin-one
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and applying to the value just stored. */
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return ++value_history_count;
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}
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/* Return a copy of the value in the history with sequence number NUM. */
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value
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access_value_history (num)
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int num;
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{
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register struct value_history_chunk *chunk;
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register int i;
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register int absnum = num;
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if (absnum <= 0)
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absnum += value_history_count;
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if (absnum <= 0)
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{
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if (num == 0)
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error ("The history is empty.");
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else if (num == 1)
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error ("There is only one value in the history.");
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else
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error ("History does not go back to $$%d.", -num);
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}
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if (absnum > value_history_count)
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error ("History has not yet reached $%d.", absnum);
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absnum--;
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/* Now absnum is always absolute and origin zero. */
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chunk = value_history_chain;
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for (i = (value_history_count - 1) / VALUE_HISTORY_CHUNK - absnum / VALUE_HISTORY_CHUNK;
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i > 0; i--)
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chunk = chunk->next;
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return value_copy (chunk->values[absnum % VALUE_HISTORY_CHUNK]);
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}
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/* Clear the value history entirely.
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Must be done when new symbol tables are loaded,
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because the type pointers become invalid. */
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void
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clear_value_history ()
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{
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register struct value_history_chunk *next;
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register int i;
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register value val;
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while (value_history_chain)
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{
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for (i = 0; i < VALUE_HISTORY_CHUNK; i++)
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if ((val = value_history_chain->values[i]) != NULL)
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free ((PTR)val);
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next = value_history_chain->next;
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free ((PTR)value_history_chain);
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value_history_chain = next;
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}
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value_history_count = 0;
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}
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static void
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show_values (num_exp, from_tty)
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char *num_exp;
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int from_tty;
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{
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register int i;
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register value val;
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static int num = 1;
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if (num_exp)
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{
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if (num_exp[0] == '+' && num_exp[1] == '\0')
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/* "info history +" should print from the stored position. */
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;
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else
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/* "info history <exp>" should print around value number <exp>. */
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num = parse_and_eval_address (num_exp) - 5;
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}
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else
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{
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/* "info history" means print the last 10 values. */
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num = value_history_count - 9;
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}
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if (num <= 0)
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num = 1;
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for (i = num; i < num + 10 && i <= value_history_count; i++)
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{
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||
val = access_value_history (i);
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printf_filtered ("$%d = ", i);
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value_print (val, stdout, 0, Val_pretty_default);
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printf_filtered ("\n");
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||
}
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/* The next "info history +" should start after what we just printed. */
|
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num += 10;
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|
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/* Hitting just return after this command should do the same thing as
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"info history +". If num_exp is null, this is unnecessary, since
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"info history +" is not useful after "info history". */
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if (from_tty && num_exp)
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{
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num_exp[0] = '+';
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num_exp[1] = '\0';
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||
}
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||
}
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||
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||
/* Internal variables. These are variables within the debugger
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||
that hold values assigned by debugger commands.
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The user refers to them with a '$' prefix
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that does not appear in the variable names stored internally. */
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||
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||
static struct internalvar *internalvars;
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||
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||
/* Look up an internal variable with name NAME. NAME should not
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normally include a dollar sign.
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||
|
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If the specified internal variable does not exist,
|
||
one is created, with a void value. */
|
||
|
||
struct internalvar *
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||
lookup_internalvar (name)
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||
char *name;
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||
{
|
||
register struct internalvar *var;
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||
|
||
for (var = internalvars; var; var = var->next)
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||
if (STREQ (var->name, name))
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return var;
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||
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||
var = (struct internalvar *) xmalloc (sizeof (struct internalvar));
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||
var->name = concat (name, NULL);
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||
var->value = allocate_value (builtin_type_void);
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release_value (var->value);
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var->next = internalvars;
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internalvars = var;
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||
return var;
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||
}
|
||
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value
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||
value_of_internalvar (var)
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||
struct internalvar *var;
|
||
{
|
||
register value val;
|
||
|
||
#ifdef IS_TRAPPED_INTERNALVAR
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if (IS_TRAPPED_INTERNALVAR (var->name))
|
||
return VALUE_OF_TRAPPED_INTERNALVAR (var);
|
||
#endif
|
||
|
||
val = value_copy (var->value);
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if (VALUE_LAZY (val))
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value_fetch_lazy (val);
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VALUE_LVAL (val) = lval_internalvar;
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||
VALUE_INTERNALVAR (val) = var;
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||
return val;
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||
}
|
||
|
||
void
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||
set_internalvar_component (var, offset, bitpos, bitsize, newval)
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||
struct internalvar *var;
|
||
int offset, bitpos, bitsize;
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||
value newval;
|
||
{
|
||
register char *addr = VALUE_CONTENTS (var->value) + offset;
|
||
|
||
#ifdef IS_TRAPPED_INTERNALVAR
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||
if (IS_TRAPPED_INTERNALVAR (var->name))
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||
SET_TRAPPED_INTERNALVAR (var, newval, bitpos, bitsize, offset);
|
||
#endif
|
||
|
||
if (bitsize)
|
||
modify_field (addr, (int) value_as_long (newval),
|
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bitpos, bitsize);
|
||
else
|
||
memcpy (addr, VALUE_CONTENTS (newval), TYPE_LENGTH (VALUE_TYPE (newval)));
|
||
}
|
||
|
||
void
|
||
set_internalvar (var, val)
|
||
struct internalvar *var;
|
||
value val;
|
||
{
|
||
#ifdef IS_TRAPPED_INTERNALVAR
|
||
if (IS_TRAPPED_INTERNALVAR (var->name))
|
||
SET_TRAPPED_INTERNALVAR (var, val, 0, 0, 0);
|
||
#endif
|
||
|
||
free ((PTR)var->value);
|
||
var->value = value_copy (val);
|
||
/* Force the value to be fetched from the target now, to avoid problems
|
||
later when this internalvar is referenced and the target is gone or
|
||
has changed. */
|
||
if (VALUE_LAZY (var->value))
|
||
value_fetch_lazy (var->value);
|
||
release_value (var->value);
|
||
}
|
||
|
||
char *
|
||
internalvar_name (var)
|
||
struct internalvar *var;
|
||
{
|
||
return var->name;
|
||
}
|
||
|
||
/* Free all internalvars. Done when new symtabs are loaded,
|
||
because that makes the values invalid. */
|
||
|
||
void
|
||
clear_internalvars ()
|
||
{
|
||
register struct internalvar *var;
|
||
|
||
while (internalvars)
|
||
{
|
||
var = internalvars;
|
||
internalvars = var->next;
|
||
free ((PTR)var->name);
|
||
free ((PTR)var->value);
|
||
free ((PTR)var);
|
||
}
|
||
}
|
||
|
||
static void
|
||
show_convenience (ignore, from_tty)
|
||
char *ignore;
|
||
int from_tty;
|
||
{
|
||
register struct internalvar *var;
|
||
int varseen = 0;
|
||
|
||
for (var = internalvars; var; var = var->next)
|
||
{
|
||
#ifdef IS_TRAPPED_INTERNALVAR
|
||
if (IS_TRAPPED_INTERNALVAR (var->name))
|
||
continue;
|
||
#endif
|
||
if (!varseen)
|
||
{
|
||
varseen = 1;
|
||
}
|
||
printf_filtered ("$%s = ", var->name);
|
||
value_print (var->value, stdout, 0, Val_pretty_default);
|
||
printf_filtered ("\n");
|
||
}
|
||
if (!varseen)
|
||
printf ("No debugger convenience variables now defined.\n\
|
||
Convenience variables have names starting with \"$\";\n\
|
||
use \"set\" as in \"set $foo = 5\" to define them.\n");
|
||
}
|
||
|
||
/* Extract a value as a C number (either long or double).
|
||
Knows how to convert fixed values to double, or
|
||
floating values to long.
|
||
Does not deallocate the value. */
|
||
|
||
LONGEST
|
||
value_as_long (val)
|
||
register value val;
|
||
{
|
||
/* This coerces arrays and functions, which is necessary (e.g.
|
||
in disassemble_command). It also dereferences references, which
|
||
I suspect is the most logical thing to do. */
|
||
if (TYPE_CODE (VALUE_TYPE (val)) != TYPE_CODE_ENUM)
|
||
COERCE_ARRAY (val);
|
||
return unpack_long (VALUE_TYPE (val), VALUE_CONTENTS (val));
|
||
}
|
||
|
||
double
|
||
value_as_double (val)
|
||
register value val;
|
||
{
|
||
double foo;
|
||
int inv;
|
||
|
||
foo = unpack_double (VALUE_TYPE (val), VALUE_CONTENTS (val), &inv);
|
||
if (inv)
|
||
error ("Invalid floating value found in program.");
|
||
return foo;
|
||
}
|
||
/* Extract a value as a C pointer.
|
||
Does not deallocate the value. */
|
||
CORE_ADDR
|
||
value_as_pointer (val)
|
||
value val;
|
||
{
|
||
/* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
|
||
whether we want this to be true eventually. */
|
||
return ADDR_BITS_REMOVE(value_as_long (val));
|
||
}
|
||
|
||
/* Unpack raw data (copied from debugee, target byte order) at VALADDR
|
||
as a long, or as a double, assuming the raw data is described
|
||
by type TYPE. Knows how to convert different sizes of values
|
||
and can convert between fixed and floating point. We don't assume
|
||
any alignment for the raw data. Return value is in host byte order.
|
||
|
||
If you want functions and arrays to be coerced to pointers, and
|
||
references to be dereferenced, call value_as_long() instead.
|
||
|
||
C++: It is assumed that the front-end has taken care of
|
||
all matters concerning pointers to members. A pointer
|
||
to member which reaches here is considered to be equivalent
|
||
to an INT (or some size). After all, it is only an offset. */
|
||
|
||
/* FIXME: This should be rewritten as a switch statement for speed and
|
||
ease of comprehension. */
|
||
|
||
LONGEST
|
||
unpack_long (type, valaddr)
|
||
struct type *type;
|
||
char *valaddr;
|
||
{
|
||
register enum type_code code = TYPE_CODE (type);
|
||
register int len = TYPE_LENGTH (type);
|
||
register int nosign = TYPE_UNSIGNED (type);
|
||
|
||
if (code == TYPE_CODE_ENUM || code == TYPE_CODE_BOOL)
|
||
code = TYPE_CODE_INT;
|
||
if (code == TYPE_CODE_FLT)
|
||
{
|
||
if (len == sizeof (float))
|
||
{
|
||
float retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
|
||
if (len == sizeof (double))
|
||
{
|
||
double retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
else
|
||
{
|
||
error ("Unexpected type of floating point number.");
|
||
}
|
||
}
|
||
else if (code == TYPE_CODE_INT && nosign)
|
||
{
|
||
if (len == sizeof (char))
|
||
{
|
||
unsigned char retval = * (unsigned char *) valaddr;
|
||
/* SWAP_TARGET_AND_HOST (&retval, sizeof (unsigned char)); */
|
||
return retval;
|
||
}
|
||
|
||
if (len == sizeof (short))
|
||
{
|
||
unsigned short retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
|
||
if (len == sizeof (int))
|
||
{
|
||
unsigned int retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
|
||
if (len == sizeof (long))
|
||
{
|
||
unsigned long retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
#ifdef CC_HAS_LONG_LONG
|
||
if (len == sizeof (long long))
|
||
{
|
||
unsigned long long retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
#endif
|
||
else
|
||
{
|
||
error ("That operation is not possible on an integer of that size.");
|
||
}
|
||
}
|
||
else if (code == TYPE_CODE_INT)
|
||
{
|
||
if (len == sizeof (char))
|
||
{
|
||
SIGNED char retval; /* plain chars might be unsigned on host */
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
|
||
if (len == sizeof (short))
|
||
{
|
||
short retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
|
||
if (len == sizeof (int))
|
||
{
|
||
int retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
|
||
if (len == sizeof (long))
|
||
{
|
||
long retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
|
||
#ifdef CC_HAS_LONG_LONG
|
||
if (len == sizeof (long long))
|
||
{
|
||
long long retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
#endif
|
||
else
|
||
{
|
||
error ("That operation is not possible on an integer of that size.");
|
||
}
|
||
}
|
||
/* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
|
||
whether we want this to be true eventually. */
|
||
else if (code == TYPE_CODE_PTR || code == TYPE_CODE_REF)
|
||
{
|
||
if (len == sizeof(long))
|
||
{
|
||
unsigned long retval;
|
||
memcpy (&retval, valaddr, sizeof(retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof(retval));
|
||
return retval;
|
||
}
|
||
else if (len == sizeof(short))
|
||
{
|
||
unsigned short retval;
|
||
memcpy (&retval, valaddr, len);
|
||
SWAP_TARGET_AND_HOST (&retval, len);
|
||
return retval;
|
||
}
|
||
else if (len == sizeof(int))
|
||
{
|
||
unsigned int retval;
|
||
memcpy (&retval, valaddr, len);
|
||
SWAP_TARGET_AND_HOST (&retval, len);
|
||
return retval;
|
||
}
|
||
#ifdef CC_HAS_LONG_LONG
|
||
else if (len == sizeof(long long))
|
||
{
|
||
unsigned long long retval;
|
||
memcpy (&retval, valaddr, len);
|
||
SWAP_TARGET_AND_HOST (&retval, len);
|
||
return retval;
|
||
}
|
||
#endif
|
||
}
|
||
else if (code == TYPE_CODE_MEMBER)
|
||
error ("not implemented: member types in unpack_long");
|
||
else if (code == TYPE_CODE_CHAR)
|
||
return *(unsigned char *)valaddr;
|
||
|
||
error ("Value not integer or pointer.");
|
||
return 0; /* For lint -- never reached */
|
||
}
|
||
|
||
/* Return a double value from the specified type and address.
|
||
INVP points to an int which is set to 0 for valid value,
|
||
1 for invalid value (bad float format). In either case,
|
||
the returned double is OK to use. Argument is in target
|
||
format, result is in host format. */
|
||
|
||
double
|
||
unpack_double (type, valaddr, invp)
|
||
struct type *type;
|
||
char *valaddr;
|
||
int *invp;
|
||
{
|
||
register enum type_code code = TYPE_CODE (type);
|
||
register int len = TYPE_LENGTH (type);
|
||
register int nosign = TYPE_UNSIGNED (type);
|
||
|
||
*invp = 0; /* Assume valid. */
|
||
if (code == TYPE_CODE_FLT)
|
||
{
|
||
if (INVALID_FLOAT (valaddr, len))
|
||
{
|
||
*invp = 1;
|
||
return 1.234567891011121314;
|
||
}
|
||
|
||
if (len == sizeof (float))
|
||
{
|
||
float retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
|
||
if (len == sizeof (double))
|
||
{
|
||
double retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
else
|
||
{
|
||
error ("Unexpected type of floating point number.");
|
||
return 0; /* Placate lint. */
|
||
}
|
||
}
|
||
else if (nosign) {
|
||
/* Unsigned -- be sure we compensate for signed LONGEST. */
|
||
return (unsigned LONGEST) unpack_long (type, valaddr);
|
||
} else {
|
||
/* Signed -- we are OK with unpack_long. */
|
||
return unpack_long (type, valaddr);
|
||
}
|
||
}
|
||
|
||
/* Unpack raw data (copied from debugee, target byte order) at VALADDR
|
||
as a CORE_ADDR, assuming the raw data is described by type TYPE.
|
||
We don't assume any alignment for the raw data. Return value is in
|
||
host byte order.
|
||
|
||
If you want functions and arrays to be coerced to pointers, and
|
||
references to be dereferenced, call value_as_pointer() instead.
|
||
|
||
C++: It is assumed that the front-end has taken care of
|
||
all matters concerning pointers to members. A pointer
|
||
to member which reaches here is considered to be equivalent
|
||
to an INT (or some size). After all, it is only an offset. */
|
||
|
||
CORE_ADDR
|
||
unpack_pointer (type, valaddr)
|
||
struct type *type;
|
||
char *valaddr;
|
||
{
|
||
#if 0
|
||
/* The user should be able to use an int (e.g. 0x7892) in contexts
|
||
where a pointer is expected. So this doesn't do enough. */
|
||
register enum type_code code = TYPE_CODE (type);
|
||
register int len = TYPE_LENGTH (type);
|
||
|
||
if (code == TYPE_CODE_PTR
|
||
|| code == TYPE_CODE_REF)
|
||
{
|
||
if (len == sizeof (CORE_ADDR))
|
||
{
|
||
CORE_ADDR retval;
|
||
memcpy (&retval, valaddr, sizeof (retval));
|
||
SWAP_TARGET_AND_HOST (&retval, sizeof (retval));
|
||
return retval;
|
||
}
|
||
error ("Unrecognized pointer size.");
|
||
}
|
||
else if (code == TYPE_CODE_MEMBER)
|
||
error ("not implemented: member types in unpack_pointer");
|
||
|
||
error ("Value is not a pointer.");
|
||
return 0; /* For lint -- never reached */
|
||
#else
|
||
/* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
|
||
whether we want this to be true eventually. */
|
||
return unpack_long (type, valaddr);
|
||
#endif
|
||
}
|
||
|
||
/* Given a value ARG1 (offset by OFFSET bytes)
|
||
of a struct or union type ARG_TYPE,
|
||
extract and return the value of one of its fields.
|
||
FIELDNO says which field.
|
||
|
||
For C++, must also be able to return values from static fields */
|
||
|
||
value
|
||
value_primitive_field (arg1, offset, fieldno, arg_type)
|
||
register value arg1;
|
||
int offset;
|
||
register int fieldno;
|
||
register struct type *arg_type;
|
||
{
|
||
register value v;
|
||
register struct type *type;
|
||
|
||
check_stub_type (arg_type);
|
||
type = TYPE_FIELD_TYPE (arg_type, fieldno);
|
||
|
||
/* Handle packed fields */
|
||
|
||
offset += TYPE_FIELD_BITPOS (arg_type, fieldno) / 8;
|
||
if (TYPE_FIELD_BITSIZE (arg_type, fieldno))
|
||
{
|
||
v = value_from_longest (type,
|
||
unpack_field_as_long (arg_type,
|
||
VALUE_CONTENTS (arg1),
|
||
fieldno));
|
||
VALUE_BITPOS (v) = TYPE_FIELD_BITPOS (arg_type, fieldno) % 8;
|
||
VALUE_BITSIZE (v) = TYPE_FIELD_BITSIZE (arg_type, fieldno);
|
||
}
|
||
else
|
||
{
|
||
v = allocate_value (type);
|
||
if (VALUE_LAZY (arg1))
|
||
VALUE_LAZY (v) = 1;
|
||
else
|
||
memcpy (VALUE_CONTENTS_RAW (v), VALUE_CONTENTS_RAW (arg1) + offset,
|
||
TYPE_LENGTH (type));
|
||
}
|
||
VALUE_LVAL (v) = VALUE_LVAL (arg1);
|
||
if (VALUE_LVAL (arg1) == lval_internalvar)
|
||
VALUE_LVAL (v) = lval_internalvar_component;
|
||
VALUE_ADDRESS (v) = VALUE_ADDRESS (arg1);
|
||
VALUE_OFFSET (v) = offset + VALUE_OFFSET (arg1);
|
||
return v;
|
||
}
|
||
|
||
/* Given a value ARG1 of a struct or union type,
|
||
extract and return the value of one of its fields.
|
||
FIELDNO says which field.
|
||
|
||
For C++, must also be able to return values from static fields */
|
||
|
||
value
|
||
value_field (arg1, fieldno)
|
||
register value arg1;
|
||
register int fieldno;
|
||
{
|
||
return value_primitive_field (arg1, 0, fieldno, VALUE_TYPE (arg1));
|
||
}
|
||
|
||
/* Return a non-virtual function as a value.
|
||
F is the list of member functions which contains the desired method.
|
||
J is an index into F which provides the desired method. */
|
||
|
||
value
|
||
value_fn_field (arg1p, f, j, type, offset)
|
||
value *arg1p;
|
||
struct fn_field *f;
|
||
int j;
|
||
struct type *type;
|
||
int offset;
|
||
{
|
||
register value v;
|
||
register struct type *ftype = TYPE_FN_FIELD_TYPE (f, j);
|
||
struct symbol *sym;
|
||
|
||
sym = lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
|
||
0, VAR_NAMESPACE, 0, NULL);
|
||
if (! sym) error ("Internal error: could not find physical method named %s",
|
||
TYPE_FN_FIELD_PHYSNAME (f, j));
|
||
|
||
v = allocate_value (ftype);
|
||
VALUE_ADDRESS (v) = BLOCK_START (SYMBOL_BLOCK_VALUE (sym));
|
||
VALUE_TYPE (v) = ftype;
|
||
|
||
if (arg1p)
|
||
{
|
||
if (type != VALUE_TYPE (*arg1p))
|
||
*arg1p = value_ind (value_cast (lookup_pointer_type (type),
|
||
value_addr (*arg1p)));
|
||
|
||
/* Move the `this' pointer according to the offset. */
|
||
VALUE_OFFSET (*arg1p) += offset;
|
||
}
|
||
|
||
return v;
|
||
}
|
||
|
||
/* Return a virtual function as a value.
|
||
ARG1 is the object which provides the virtual function
|
||
table pointer. *ARG1P is side-effected in calling this function.
|
||
F is the list of member functions which contains the desired virtual
|
||
function.
|
||
J is an index into F which provides the desired virtual function.
|
||
|
||
TYPE is the type in which F is located. */
|
||
value
|
||
value_virtual_fn_field (arg1p, f, j, type, offset)
|
||
value *arg1p;
|
||
struct fn_field *f;
|
||
int j;
|
||
struct type *type;
|
||
int offset;
|
||
{
|
||
value arg1 = *arg1p;
|
||
/* First, get the virtual function table pointer. That comes
|
||
with a strange type, so cast it to type `pointer to long' (which
|
||
should serve just fine as a function type). Then, index into
|
||
the table, and convert final value to appropriate function type. */
|
||
value entry, vfn, vtbl;
|
||
value vi = value_from_longest (builtin_type_int,
|
||
(LONGEST) TYPE_FN_FIELD_VOFFSET (f, j));
|
||
struct type *fcontext = TYPE_FN_FIELD_FCONTEXT (f, j);
|
||
struct type *context;
|
||
if (fcontext == NULL)
|
||
/* We don't have an fcontext (e.g. the program was compiled with
|
||
g++ version 1). Try to get the vtbl from the TYPE_VPTR_BASETYPE.
|
||
This won't work right for multiple inheritance, but at least we
|
||
should do as well as GDB 3.x did. */
|
||
fcontext = TYPE_VPTR_BASETYPE (type);
|
||
context = lookup_pointer_type (fcontext);
|
||
/* Now context is a pointer to the basetype containing the vtbl. */
|
||
if (TYPE_TARGET_TYPE (context) != VALUE_TYPE (arg1))
|
||
arg1 = value_ind (value_cast (context, value_addr (arg1)));
|
||
|
||
context = VALUE_TYPE (arg1);
|
||
/* Now context is the basetype containing the vtbl. */
|
||
|
||
/* This type may have been defined before its virtual function table
|
||
was. If so, fill in the virtual function table entry for the
|
||
type now. */
|
||
if (TYPE_VPTR_FIELDNO (context) < 0)
|
||
fill_in_vptr_fieldno (context);
|
||
|
||
/* The virtual function table is now an array of structures
|
||
which have the form { int16 offset, delta; void *pfn; }. */
|
||
vtbl = value_ind (value_primitive_field (arg1, 0,
|
||
TYPE_VPTR_FIELDNO (context),
|
||
TYPE_VPTR_BASETYPE (context)));
|
||
|
||
/* Index into the virtual function table. This is hard-coded because
|
||
looking up a field is not cheap, and it may be important to save
|
||
time, e.g. if the user has set a conditional breakpoint calling
|
||
a virtual function. */
|
||
entry = value_subscript (vtbl, vi);
|
||
|
||
/* Move the `this' pointer according to the virtual function table. */
|
||
VALUE_OFFSET (arg1) += value_as_long (value_field (entry, 0)) + offset;
|
||
if (! VALUE_LAZY (arg1))
|
||
{
|
||
VALUE_LAZY (arg1) = 1;
|
||
value_fetch_lazy (arg1);
|
||
}
|
||
|
||
vfn = value_field (entry, 2);
|
||
/* Reinstantiate the function pointer with the correct type. */
|
||
VALUE_TYPE (vfn) = lookup_pointer_type (TYPE_FN_FIELD_TYPE (f, j));
|
||
|
||
*arg1p = arg1;
|
||
return vfn;
|
||
}
|
||
|
||
/* ARG is a pointer to an object we know to be at least
|
||
a DTYPE. BTYPE is the most derived basetype that has
|
||
already been searched (and need not be searched again).
|
||
After looking at the vtables between BTYPE and DTYPE,
|
||
return the most derived type we find. The caller must
|
||
be satisfied when the return value == DTYPE.
|
||
|
||
FIXME-tiemann: should work with dossier entries as well. */
|
||
|
||
static value
|
||
value_headof (in_arg, btype, dtype)
|
||
value in_arg;
|
||
struct type *btype, *dtype;
|
||
{
|
||
/* First collect the vtables we must look at for this object. */
|
||
/* FIXME-tiemann: right now, just look at top-most vtable. */
|
||
value arg, vtbl, entry, best_entry = 0;
|
||
int i, nelems;
|
||
int offset, best_offset = 0;
|
||
struct symbol *sym;
|
||
CORE_ADDR pc_for_sym;
|
||
char *demangled_name;
|
||
struct minimal_symbol *msymbol;
|
||
|
||
btype = TYPE_VPTR_BASETYPE (dtype);
|
||
check_stub_type (btype);
|
||
arg = in_arg;
|
||
if (btype != dtype)
|
||
arg = value_cast (lookup_pointer_type (btype), arg);
|
||
vtbl = value_ind (value_field (value_ind (arg), TYPE_VPTR_FIELDNO (btype)));
|
||
|
||
/* Check that VTBL looks like it points to a virtual function table. */
|
||
msymbol = lookup_minimal_symbol_by_pc (VALUE_ADDRESS (vtbl));
|
||
if (msymbol == NULL
|
||
|| !VTBL_PREFIX_P (demangled_name = SYMBOL_NAME (msymbol)))
|
||
{
|
||
/* If we expected to find a vtable, but did not, let the user
|
||
know that we aren't happy, but don't throw an error.
|
||
FIXME: there has to be a better way to do this. */
|
||
struct type *error_type = (struct type *)xmalloc (sizeof (struct type));
|
||
memcpy (error_type, VALUE_TYPE (in_arg), sizeof (struct type));
|
||
TYPE_NAME (error_type) = savestring ("suspicious *", sizeof ("suspicious *"));
|
||
VALUE_TYPE (in_arg) = error_type;
|
||
return in_arg;
|
||
}
|
||
|
||
/* Now search through the virtual function table. */
|
||
entry = value_ind (vtbl);
|
||
nelems = longest_to_int (value_as_long (value_field (entry, 2)));
|
||
for (i = 1; i <= nelems; i++)
|
||
{
|
||
entry = value_subscript (vtbl, value_from_longest (builtin_type_int,
|
||
(LONGEST) i));
|
||
offset = longest_to_int (value_as_long (value_field (entry, 0)));
|
||
/* If we use '<=' we can handle single inheritance
|
||
* where all offsets are zero - just use the first entry found. */
|
||
if (offset <= best_offset)
|
||
{
|
||
best_offset = offset;
|
||
best_entry = entry;
|
||
}
|
||
}
|
||
/* Move the pointer according to BEST_ENTRY's offset, and figure
|
||
out what type we should return as the new pointer. */
|
||
if (best_entry == 0)
|
||
{
|
||
/* An alternative method (which should no longer be necessary).
|
||
* But we leave it in for future use, when we will hopefully
|
||
* have optimizes the vtable to use thunks instead of offsets. */
|
||
/* Use the name of vtable itself to extract a base type. */
|
||
demangled_name += 4; /* Skip _vt$ prefix. */
|
||
}
|
||
else
|
||
{
|
||
pc_for_sym = value_as_pointer (value_field (best_entry, 2));
|
||
sym = find_pc_function (pc_for_sym);
|
||
demangled_name = cplus_demangle (SYMBOL_NAME (sym), DMGL_ANSI);
|
||
*(strchr (demangled_name, ':')) = '\0';
|
||
}
|
||
sym = lookup_symbol (demangled_name, 0, VAR_NAMESPACE, 0, 0);
|
||
if (sym == NULL)
|
||
error ("could not find type declaration for `%s'", demangled_name);
|
||
if (best_entry)
|
||
{
|
||
free (demangled_name);
|
||
arg = value_add (value_cast (builtin_type_int, arg),
|
||
value_field (best_entry, 0));
|
||
}
|
||
else arg = in_arg;
|
||
VALUE_TYPE (arg) = lookup_pointer_type (SYMBOL_TYPE (sym));
|
||
return arg;
|
||
}
|
||
|
||
/* ARG is a pointer object of type TYPE. If TYPE has virtual
|
||
function tables, probe ARG's tables (including the vtables
|
||
of its baseclasses) to figure out the most derived type that ARG
|
||
could actually be a pointer to. */
|
||
|
||
value
|
||
value_from_vtable_info (arg, type)
|
||
value arg;
|
||
struct type *type;
|
||
{
|
||
/* Take care of preliminaries. */
|
||
if (TYPE_VPTR_FIELDNO (type) < 0)
|
||
fill_in_vptr_fieldno (type);
|
||
if (TYPE_VPTR_FIELDNO (type) < 0 || VALUE_REPEATED (arg))
|
||
return 0;
|
||
|
||
return value_headof (arg, 0, type);
|
||
}
|
||
|
||
/* Compute the offset of the baseclass which is
|
||
the INDEXth baseclass of class TYPE, for a value ARG,
|
||
wih extra offset of OFFSET.
|
||
The result is the offste of the baseclass value relative
|
||
to (the address of)(ARG) + OFFSET.
|
||
|
||
-1 is returned on error. */
|
||
|
||
int
|
||
baseclass_offset (type, index, arg, offset)
|
||
struct type *type;
|
||
int index;
|
||
value arg;
|
||
int offset;
|
||
{
|
||
struct type *basetype = TYPE_BASECLASS (type, index);
|
||
|
||
if (BASETYPE_VIA_VIRTUAL (type, index))
|
||
{
|
||
/* Must hunt for the pointer to this virtual baseclass. */
|
||
register int i, len = TYPE_NFIELDS (type);
|
||
register int n_baseclasses = TYPE_N_BASECLASSES (type);
|
||
char *vbase_name, *type_name = type_name_no_tag (basetype);
|
||
|
||
vbase_name = (char *)alloca (strlen (type_name) + 8);
|
||
sprintf (vbase_name, "_vb%c%s", CPLUS_MARKER, type_name);
|
||
/* First look for the virtual baseclass pointer
|
||
in the fields. */
|
||
for (i = n_baseclasses; i < len; i++)
|
||
{
|
||
if (STREQ (vbase_name, TYPE_FIELD_NAME (type, i)))
|
||
{
|
||
CORE_ADDR addr
|
||
= unpack_pointer (TYPE_FIELD_TYPE (type, i),
|
||
VALUE_CONTENTS (arg) + VALUE_OFFSET (arg)
|
||
+ offset
|
||
+ (TYPE_FIELD_BITPOS (type, i) / 8));
|
||
|
||
if (VALUE_LVAL (arg) != lval_memory)
|
||
return -1;
|
||
|
||
return addr -
|
||
(LONGEST) (VALUE_ADDRESS (arg) + VALUE_OFFSET (arg) + offset);
|
||
}
|
||
}
|
||
/* Not in the fields, so try looking through the baseclasses. */
|
||
for (i = index+1; i < n_baseclasses; i++)
|
||
{
|
||
int boffset =
|
||
baseclass_offset (type, i, arg, offset);
|
||
if (boffset)
|
||
return boffset;
|
||
}
|
||
/* Not found. */
|
||
return -1;
|
||
}
|
||
|
||
/* Baseclass is easily computed. */
|
||
return TYPE_BASECLASS_BITPOS (type, index) / 8;
|
||
}
|
||
|
||
/* Compute the address of the baseclass which is
|
||
the INDEXth baseclass of class TYPE. The TYPE base
|
||
of the object is at VALADDR.
|
||
|
||
If ERRP is non-NULL, set *ERRP to be the errno code of any error,
|
||
or 0 if no error. In that case the return value is not the address
|
||
of the baseclasss, but the address which could not be read
|
||
successfully. */
|
||
|
||
/* FIXME Fix remaining uses of baseclass_addr to use baseclass_offset */
|
||
|
||
char *
|
||
baseclass_addr (type, index, valaddr, valuep, errp)
|
||
struct type *type;
|
||
int index;
|
||
char *valaddr;
|
||
value *valuep;
|
||
int *errp;
|
||
{
|
||
struct type *basetype = TYPE_BASECLASS (type, index);
|
||
|
||
if (errp)
|
||
*errp = 0;
|
||
|
||
if (BASETYPE_VIA_VIRTUAL (type, index))
|
||
{
|
||
/* Must hunt for the pointer to this virtual baseclass. */
|
||
register int i, len = TYPE_NFIELDS (type);
|
||
register int n_baseclasses = TYPE_N_BASECLASSES (type);
|
||
char *vbase_name, *type_name = type_name_no_tag (basetype);
|
||
|
||
vbase_name = (char *)alloca (strlen (type_name) + 8);
|
||
sprintf (vbase_name, "_vb%c%s", CPLUS_MARKER, type_name);
|
||
/* First look for the virtual baseclass pointer
|
||
in the fields. */
|
||
for (i = n_baseclasses; i < len; i++)
|
||
{
|
||
if (STREQ (vbase_name, TYPE_FIELD_NAME (type, i)))
|
||
{
|
||
value val = allocate_value (basetype);
|
||
CORE_ADDR addr;
|
||
int status;
|
||
|
||
addr
|
||
= unpack_pointer (TYPE_FIELD_TYPE (type, i),
|
||
valaddr + (TYPE_FIELD_BITPOS (type, i) / 8));
|
||
|
||
status = target_read_memory (addr,
|
||
VALUE_CONTENTS_RAW (val),
|
||
TYPE_LENGTH (basetype));
|
||
VALUE_LVAL (val) = lval_memory;
|
||
VALUE_ADDRESS (val) = addr;
|
||
|
||
if (status != 0)
|
||
{
|
||
if (valuep)
|
||
*valuep = NULL;
|
||
release_value (val);
|
||
value_free (val);
|
||
if (errp)
|
||
*errp = status;
|
||
return (char *)addr;
|
||
}
|
||
else
|
||
{
|
||
if (valuep)
|
||
*valuep = val;
|
||
return (char *) VALUE_CONTENTS (val);
|
||
}
|
||
}
|
||
}
|
||
/* Not in the fields, so try looking through the baseclasses. */
|
||
for (i = index+1; i < n_baseclasses; i++)
|
||
{
|
||
char *baddr;
|
||
|
||
baddr = baseclass_addr (type, i, valaddr, valuep, errp);
|
||
if (baddr)
|
||
return baddr;
|
||
}
|
||
/* Not found. */
|
||
if (valuep)
|
||
*valuep = 0;
|
||
return 0;
|
||
}
|
||
|
||
/* Baseclass is easily computed. */
|
||
if (valuep)
|
||
*valuep = 0;
|
||
return valaddr + TYPE_BASECLASS_BITPOS (type, index) / 8;
|
||
}
|
||
|
||
/* Unpack a field FIELDNO of the specified TYPE, from the anonymous object at
|
||
VALADDR.
|
||
|
||
Extracting bits depends on endianness of the machine. Compute the
|
||
number of least significant bits to discard. For big endian machines,
|
||
we compute the total number of bits in the anonymous object, subtract
|
||
off the bit count from the MSB of the object to the MSB of the
|
||
bitfield, then the size of the bitfield, which leaves the LSB discard
|
||
count. For little endian machines, the discard count is simply the
|
||
number of bits from the LSB of the anonymous object to the LSB of the
|
||
bitfield.
|
||
|
||
If the field is signed, we also do sign extension. */
|
||
|
||
LONGEST
|
||
unpack_field_as_long (type, valaddr, fieldno)
|
||
struct type *type;
|
||
char *valaddr;
|
||
int fieldno;
|
||
{
|
||
unsigned LONGEST val;
|
||
unsigned LONGEST valmask;
|
||
int bitpos = TYPE_FIELD_BITPOS (type, fieldno);
|
||
int bitsize = TYPE_FIELD_BITSIZE (type, fieldno);
|
||
int lsbcount;
|
||
|
||
memcpy (&val, valaddr + bitpos / 8, sizeof (val));
|
||
SWAP_TARGET_AND_HOST (&val, sizeof (val));
|
||
|
||
/* Extract bits. See comment above. */
|
||
|
||
#if BITS_BIG_ENDIAN
|
||
lsbcount = (sizeof val * 8 - bitpos % 8 - bitsize);
|
||
#else
|
||
lsbcount = (bitpos % 8);
|
||
#endif
|
||
val >>= lsbcount;
|
||
|
||
/* 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 ((bitsize > 0) && (bitsize < 8 * sizeof (val)))
|
||
{
|
||
valmask = (((unsigned LONGEST) 1) << bitsize) - 1;
|
||
val &= valmask;
|
||
if (!TYPE_UNSIGNED (TYPE_FIELD_TYPE (type, fieldno)))
|
||
{
|
||
if (val & (valmask ^ (valmask >> 1)))
|
||
{
|
||
val |= ~valmask;
|
||
}
|
||
}
|
||
}
|
||
return (val);
|
||
}
|
||
|
||
/* Modify the value of a bitfield. ADDR points to a block of memory in
|
||
target byte order; the bitfield starts in the byte pointed to. FIELDVAL
|
||
is the desired value of the field, in host byte order. BITPOS and BITSIZE
|
||
indicate which bits (in target bit order) comprise the bitfield. */
|
||
|
||
void
|
||
modify_field (addr, fieldval, bitpos, bitsize)
|
||
char *addr;
|
||
int fieldval;
|
||
int bitpos, bitsize;
|
||
{
|
||
long oword;
|
||
|
||
/* Reject values too big to fit in the field in question,
|
||
otherwise adjoining fields may be corrupted. */
|
||
if (bitsize < (8 * sizeof (fieldval))
|
||
&& 0 != (fieldval & ~((1<<bitsize)-1)))
|
||
error ("Value %d does not fit in %d bits.", fieldval, bitsize);
|
||
|
||
memcpy (&oword, addr, sizeof oword);
|
||
SWAP_TARGET_AND_HOST (&oword, sizeof oword); /* To host format */
|
||
|
||
/* Shifting for bit field depends on endianness of the target machine. */
|
||
#if BITS_BIG_ENDIAN
|
||
bitpos = sizeof (oword) * 8 - bitpos - bitsize;
|
||
#endif
|
||
|
||
/* Mask out old value, while avoiding shifts >= longword size */
|
||
if (bitsize < 8 * sizeof (oword))
|
||
oword &= ~(((((unsigned long)1) << bitsize) - 1) << bitpos);
|
||
else
|
||
oword &= ~((-1) << bitpos);
|
||
oword |= fieldval << bitpos;
|
||
|
||
SWAP_TARGET_AND_HOST (&oword, sizeof oword); /* To target format */
|
||
memcpy (addr, &oword, sizeof oword);
|
||
}
|
||
|
||
/* Convert C numbers into newly allocated values */
|
||
|
||
value
|
||
value_from_longest (type, num)
|
||
struct type *type;
|
||
register LONGEST num;
|
||
{
|
||
register value val = allocate_value (type);
|
||
register enum type_code code = TYPE_CODE (type);
|
||
register int len = TYPE_LENGTH (type);
|
||
|
||
/* FIXME, we assume that pointers have the same form and byte order as
|
||
integers, and that all pointers have the same form. */
|
||
if (code == TYPE_CODE_INT || code == TYPE_CODE_ENUM ||
|
||
code == TYPE_CODE_CHAR || code == TYPE_CODE_PTR ||
|
||
code == TYPE_CODE_REF || code == TYPE_CODE_BOOL)
|
||
{
|
||
if (len == sizeof (char))
|
||
* (char *) VALUE_CONTENTS_RAW (val) = num;
|
||
else if (len == sizeof (short))
|
||
* (short *) VALUE_CONTENTS_RAW (val) = num;
|
||
else if (len == sizeof (int))
|
||
* (int *) VALUE_CONTENTS_RAW (val) = num;
|
||
else if (len == sizeof (long))
|
||
* (long *) VALUE_CONTENTS_RAW (val) = num;
|
||
else if (len == sizeof (LONGEST))
|
||
* (LONGEST *) VALUE_CONTENTS_RAW (val) = num;
|
||
else
|
||
error ("Integer type encountered with unexpected data length.");
|
||
}
|
||
else
|
||
error ("Unexpected type encountered for integer constant.");
|
||
|
||
/* num was in host byte order. So now put the value's contents
|
||
into target byte order. */
|
||
SWAP_TARGET_AND_HOST (VALUE_CONTENTS_RAW (val), len);
|
||
|
||
return val;
|
||
}
|
||
|
||
value
|
||
value_from_double (type, num)
|
||
struct type *type;
|
||
double num;
|
||
{
|
||
register value val = allocate_value (type);
|
||
register enum type_code code = TYPE_CODE (type);
|
||
register int len = TYPE_LENGTH (type);
|
||
|
||
if (code == TYPE_CODE_FLT)
|
||
{
|
||
if (len == sizeof (float))
|
||
* (float *) VALUE_CONTENTS_RAW (val) = num;
|
||
else if (len == sizeof (double))
|
||
* (double *) VALUE_CONTENTS_RAW (val) = num;
|
||
else
|
||
error ("Floating type encountered with unexpected data length.");
|
||
}
|
||
else
|
||
error ("Unexpected type encountered for floating constant.");
|
||
|
||
/* num was in host byte order. So now put the value's contents
|
||
into target byte order. */
|
||
SWAP_TARGET_AND_HOST (VALUE_CONTENTS_RAW (val), len);
|
||
|
||
return val;
|
||
}
|
||
|
||
/* Deal with the value that is "about to be returned". */
|
||
|
||
/* Return the value that a function returning now
|
||
would be returning to its caller, assuming its type is VALTYPE.
|
||
RETBUF is where we look for what ought to be the contents
|
||
of the registers (in raw form). This is because it is often
|
||
desirable to restore old values to those registers
|
||
after saving the contents of interest, and then call
|
||
this function using the saved values.
|
||
struct_return is non-zero when the function in question is
|
||
using the structure return conventions on the machine in question;
|
||
0 when it is using the value returning conventions (this often
|
||
means returning pointer to where structure is vs. returning value). */
|
||
|
||
value
|
||
value_being_returned (valtype, retbuf, struct_return)
|
||
register struct type *valtype;
|
||
char retbuf[REGISTER_BYTES];
|
||
int struct_return;
|
||
/*ARGSUSED*/
|
||
{
|
||
register value val;
|
||
CORE_ADDR addr;
|
||
|
||
#if defined (EXTRACT_STRUCT_VALUE_ADDRESS)
|
||
/* If this is not defined, just use EXTRACT_RETURN_VALUE instead. */
|
||
if (struct_return) {
|
||
addr = EXTRACT_STRUCT_VALUE_ADDRESS (retbuf);
|
||
if (!addr)
|
||
error ("Function return value unknown");
|
||
return value_at (valtype, addr);
|
||
}
|
||
#endif
|
||
|
||
val = allocate_value (valtype);
|
||
EXTRACT_RETURN_VALUE (valtype, retbuf, VALUE_CONTENTS_RAW (val));
|
||
|
||
return val;
|
||
}
|
||
|
||
/* Should we use EXTRACT_STRUCT_VALUE_ADDRESS instead of
|
||
EXTRACT_RETURN_VALUE? GCC_P is true if compiled with gcc
|
||
and TYPE is the type (which is known to be struct, union or array).
|
||
|
||
On most machines, the struct convention is used unless we are
|
||
using gcc and the type is of a special size. */
|
||
/* As of about 31 Mar 93, GCC was changed to be compatible with the
|
||
native compiler. GCC 2.3.3 was the last release that did it the
|
||
old way. Since gcc2_compiled was not changed, we have no
|
||
way to correctly win in all cases, so we just do the right thing
|
||
for gcc1 and for gcc2 after this change. Thus it loses for gcc
|
||
2.0-2.3.3. This is somewhat unfortunate, but changing gcc2_compiled
|
||
would cause more chaos than dealing with some struct returns being
|
||
handled wrong. */
|
||
#if !defined (USE_STRUCT_CONVENTION)
|
||
#define USE_STRUCT_CONVENTION(gcc_p, type)\
|
||
(!((gcc_p == 1) && (TYPE_LENGTH (value_type) == 1 \
|
||
|| TYPE_LENGTH (value_type) == 2 \
|
||
|| TYPE_LENGTH (value_type) == 4 \
|
||
|| TYPE_LENGTH (value_type) == 8 \
|
||
) \
|
||
))
|
||
#endif
|
||
|
||
/* Return true if the function specified is using the structure returning
|
||
convention on this machine to return arguments, or 0 if it is using
|
||
the value returning convention. FUNCTION is the value representing
|
||
the function, FUNCADDR is the address of the function, and VALUE_TYPE
|
||
is the type returned by the function. GCC_P is nonzero if compiled
|
||
with GCC. */
|
||
|
||
int
|
||
using_struct_return (function, funcaddr, value_type, gcc_p)
|
||
value function;
|
||
CORE_ADDR funcaddr;
|
||
struct type *value_type;
|
||
int gcc_p;
|
||
/*ARGSUSED*/
|
||
{
|
||
register enum type_code code = TYPE_CODE (value_type);
|
||
|
||
if (code == TYPE_CODE_ERROR)
|
||
error ("Function return type unknown.");
|
||
|
||
if (code == TYPE_CODE_STRUCT ||
|
||
code == TYPE_CODE_UNION ||
|
||
code == TYPE_CODE_ARRAY)
|
||
return USE_STRUCT_CONVENTION (gcc_p, value_type);
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Store VAL so it will be returned if a function returns now.
|
||
Does not verify that VAL's type matches what the current
|
||
function wants to return. */
|
||
|
||
void
|
||
set_return_value (val)
|
||
value val;
|
||
{
|
||
register enum type_code code = TYPE_CODE (VALUE_TYPE (val));
|
||
double dbuf;
|
||
LONGEST lbuf;
|
||
|
||
if (code == TYPE_CODE_ERROR)
|
||
error ("Function return type unknown.");
|
||
|
||
if ( code == TYPE_CODE_STRUCT
|
||
|| code == TYPE_CODE_UNION) /* FIXME, implement struct return. */
|
||
error ("GDB does not support specifying a struct or union return value.");
|
||
|
||
/* FIXME, this is bogus. We don't know what the return conventions
|
||
are, or how values should be promoted.... */
|
||
if (code == TYPE_CODE_FLT)
|
||
{
|
||
dbuf = value_as_double (val);
|
||
|
||
STORE_RETURN_VALUE (VALUE_TYPE (val), (char *)&dbuf);
|
||
}
|
||
else
|
||
{
|
||
lbuf = value_as_long (val);
|
||
STORE_RETURN_VALUE (VALUE_TYPE (val), (char *)&lbuf);
|
||
}
|
||
}
|
||
|
||
void
|
||
_initialize_values ()
|
||
{
|
||
add_cmd ("convenience", no_class, show_convenience,
|
||
"Debugger convenience (\"$foo\") variables.\n\
|
||
These variables are created when you assign them values;\n\
|
||
thus, \"print $foo=1\" gives \"$foo\" the value 1. Values may be any type.\n\n\
|
||
A few convenience variables are given values automatically:\n\
|
||
\"$_\"holds the last address examined with \"x\" or \"info lines\",\n\
|
||
\"$__\" holds the contents of the last address examined with \"x\".",
|
||
&showlist);
|
||
|
||
add_cmd ("values", no_class, show_values,
|
||
"Elements of value history around item number IDX (or last ten).",
|
||
&showlist);
|
||
}
|