918 lines
24 KiB
C
918 lines
24 KiB
C
/* Find a variable's value in memory, for GDB, the GNU debugger.
|
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Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
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1996, 1997, 1998, 1999, 2000, 2001
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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
|
||
(at your option) any later version.
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||
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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
|
||
Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include "defs.h"
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#include "symtab.h"
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#include "gdbtypes.h"
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#include "frame.h"
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#include "value.h"
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#include "gdbcore.h"
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#include "inferior.h"
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#include "target.h"
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#include "gdb_string.h"
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#include "gdb_assert.h"
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#include "floatformat.h"
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#include "symfile.h" /* for overlay functions */
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#include "regcache.h"
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#include "builtin-regs.h"
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/* Basic byte-swapping routines. GDB has needed these for a long time...
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All extract a target-format integer at ADDR which is LEN bytes long. */
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#if TARGET_CHAR_BIT != 8 || HOST_CHAR_BIT != 8
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/* 8 bit characters are a pretty safe assumption these days, so we
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assume it throughout all these swapping routines. If we had to deal with
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9 bit characters, we would need to make len be in bits and would have
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to re-write these routines... */
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you lose
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#endif
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LONGEST
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extract_signed_integer (const void *addr, int len)
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{
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LONGEST retval;
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const unsigned char *p;
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const unsigned char *startaddr = addr;
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const unsigned char *endaddr = startaddr + len;
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if (len > (int) sizeof (LONGEST))
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error ("\
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That operation is not available on integers of more than %d bytes.",
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(int) sizeof (LONGEST));
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/* Start at the most significant end of the integer, and work towards
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the least significant. */
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if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
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{
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p = startaddr;
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/* Do the sign extension once at the start. */
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retval = ((LONGEST) * p ^ 0x80) - 0x80;
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for (++p; p < endaddr; ++p)
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retval = (retval << 8) | *p;
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}
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else
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{
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p = endaddr - 1;
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/* Do the sign extension once at the start. */
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retval = ((LONGEST) * p ^ 0x80) - 0x80;
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for (--p; p >= startaddr; --p)
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retval = (retval << 8) | *p;
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}
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return retval;
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}
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ULONGEST
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extract_unsigned_integer (const void *addr, int len)
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{
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ULONGEST retval;
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const unsigned char *p;
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const unsigned char *startaddr = addr;
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const unsigned char *endaddr = startaddr + len;
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if (len > (int) sizeof (ULONGEST))
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error ("\
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That operation is not available on integers of more than %d bytes.",
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(int) sizeof (ULONGEST));
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/* Start at the most significant end of the integer, and work towards
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the least significant. */
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retval = 0;
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if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
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{
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for (p = startaddr; p < endaddr; ++p)
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retval = (retval << 8) | *p;
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}
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else
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{
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for (p = endaddr - 1; p >= startaddr; --p)
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retval = (retval << 8) | *p;
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}
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return retval;
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}
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/* Sometimes a long long unsigned integer can be extracted as a
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LONGEST value. This is done so that we can print these values
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better. If this integer can be converted to a LONGEST, this
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function returns 1 and sets *PVAL. Otherwise it returns 0. */
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int
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extract_long_unsigned_integer (const void *addr, int orig_len, LONGEST *pval)
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{
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char *p, *first_addr;
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int len;
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len = orig_len;
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if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
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{
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for (p = (char *) addr;
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len > (int) sizeof (LONGEST) && p < (char *) addr + orig_len;
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p++)
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{
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if (*p == 0)
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len--;
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else
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break;
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}
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first_addr = p;
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}
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else
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{
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first_addr = (char *) addr;
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for (p = (char *) addr + orig_len - 1;
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len > (int) sizeof (LONGEST) && p >= (char *) addr;
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p--)
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{
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if (*p == 0)
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len--;
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else
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break;
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}
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}
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if (len <= (int) sizeof (LONGEST))
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{
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*pval = (LONGEST) extract_unsigned_integer (first_addr,
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sizeof (LONGEST));
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return 1;
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}
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return 0;
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}
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/* Treat the LEN bytes at ADDR as a target-format address, and return
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that address. ADDR is a buffer in the GDB process, not in the
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inferior.
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This function should only be used by target-specific code. It
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assumes that a pointer has the same representation as that thing's
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address represented as an integer. Some machines use word
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addresses, or similarly munged things, for certain types of
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pointers, so that assumption doesn't hold everywhere.
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Common code should use extract_typed_address instead, or something
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else based on POINTER_TO_ADDRESS. */
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CORE_ADDR
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extract_address (const void *addr, int len)
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{
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/* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
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whether we want this to be true eventually. */
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return (CORE_ADDR) extract_unsigned_integer (addr, len);
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}
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/* Treat the bytes at BUF as a pointer of type TYPE, and return the
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address it represents. */
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CORE_ADDR
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extract_typed_address (const void *buf, struct type *type)
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{
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if (TYPE_CODE (type) != TYPE_CODE_PTR
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&& TYPE_CODE (type) != TYPE_CODE_REF)
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internal_error (__FILE__, __LINE__,
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"extract_typed_address: "
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"type is not a pointer or reference");
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return POINTER_TO_ADDRESS (type, buf);
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}
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void
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store_signed_integer (void *addr, int len, LONGEST val)
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{
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unsigned char *p;
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unsigned char *startaddr = (unsigned char *) addr;
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unsigned char *endaddr = startaddr + len;
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/* Start at the least significant end of the integer, and work towards
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the most significant. */
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if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
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{
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for (p = endaddr - 1; p >= startaddr; --p)
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{
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*p = val & 0xff;
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val >>= 8;
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}
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}
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else
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{
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for (p = startaddr; p < endaddr; ++p)
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{
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*p = val & 0xff;
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val >>= 8;
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}
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}
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}
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void
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store_unsigned_integer (void *addr, int len, ULONGEST val)
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{
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unsigned char *p;
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unsigned char *startaddr = (unsigned char *) addr;
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unsigned char *endaddr = startaddr + len;
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||
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||
/* Start at the least significant end of the integer, and work towards
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the most significant. */
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||
if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
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||
{
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||
for (p = endaddr - 1; p >= startaddr; --p)
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{
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*p = val & 0xff;
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val >>= 8;
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}
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}
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else
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{
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for (p = startaddr; p < endaddr; ++p)
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{
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*p = val & 0xff;
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val >>= 8;
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}
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}
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}
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/* Store the address VAL as a LEN-byte value in target byte order at
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ADDR. ADDR is a buffer in the GDB process, not in the inferior.
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This function should only be used by target-specific code. It
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||
assumes that a pointer has the same representation as that thing's
|
||
address represented as an integer. Some machines use word
|
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addresses, or similarly munged things, for certain types of
|
||
pointers, so that assumption doesn't hold everywhere.
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||
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||
Common code should use store_typed_address instead, or something else
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||
based on ADDRESS_TO_POINTER. */
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void
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store_address (void *addr, int len, LONGEST val)
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{
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store_unsigned_integer (addr, len, val);
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}
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||
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/* Store the address ADDR as a pointer of type TYPE at BUF, in target
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form. */
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void
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store_typed_address (void *buf, struct type *type, CORE_ADDR addr)
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{
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if (TYPE_CODE (type) != TYPE_CODE_PTR
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&& TYPE_CODE (type) != TYPE_CODE_REF)
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internal_error (__FILE__, __LINE__,
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"store_typed_address: "
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"type is not a pointer or reference");
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ADDRESS_TO_POINTER (type, buf, addr);
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}
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/* Return a `value' with the contents of (virtual or cooked) register
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REGNUM as found in the specified FRAME. The register's type is
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||
determined by REGISTER_VIRTUAL_TYPE.
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||
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||
NOTE: returns NULL if register value is not available. Caller will
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check return value or die! */
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||
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struct value *
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value_of_register (int regnum, struct frame_info *frame)
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{
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||
CORE_ADDR addr;
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||
int optim;
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||
struct value *reg_val;
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char *raw_buffer = (char*) alloca (MAX_REGISTER_RAW_SIZE);
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enum lval_type lval;
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/* Builtin registers lie completly outside of the range of normal
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registers. Catch them early so that the target never sees them. */
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if (regnum >= NUM_REGS + NUM_PSEUDO_REGS)
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return value_of_builtin_reg (regnum, deprecated_selected_frame);
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get_saved_register (raw_buffer, &optim, &addr,
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frame, regnum, &lval);
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||
|
||
/* FIXME: cagney/2002-05-15: This test is just bogus.
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||
|
||
It indicates that the target failed to supply a value for a
|
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register because it was "not available" at this time. Problem
|
||
is, the target still has the register and so get saved_register()
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||
may be returning a value saved on the stack. */
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||
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||
if (register_cached (regnum) < 0)
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return NULL; /* register value not available */
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||
|
||
reg_val = allocate_value (REGISTER_VIRTUAL_TYPE (regnum));
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||
|
||
/* Convert raw data to virtual format if necessary. */
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||
|
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if (REGISTER_CONVERTIBLE (regnum))
|
||
{
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REGISTER_CONVERT_TO_VIRTUAL (regnum, REGISTER_VIRTUAL_TYPE (regnum),
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raw_buffer, VALUE_CONTENTS_RAW (reg_val));
|
||
}
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||
else if (REGISTER_RAW_SIZE (regnum) == REGISTER_VIRTUAL_SIZE (regnum))
|
||
memcpy (VALUE_CONTENTS_RAW (reg_val), raw_buffer,
|
||
REGISTER_RAW_SIZE (regnum));
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||
else
|
||
internal_error (__FILE__, __LINE__,
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||
"Register \"%s\" (%d) has conflicting raw (%d) and virtual (%d) size",
|
||
REGISTER_NAME (regnum),
|
||
regnum,
|
||
REGISTER_RAW_SIZE (regnum),
|
||
REGISTER_VIRTUAL_SIZE (regnum));
|
||
VALUE_LVAL (reg_val) = lval;
|
||
VALUE_ADDRESS (reg_val) = addr;
|
||
VALUE_REGNO (reg_val) = regnum;
|
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VALUE_OPTIMIZED_OUT (reg_val) = optim;
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return reg_val;
|
||
}
|
||
|
||
/* Given a pointer of type TYPE in target form in BUF, return the
|
||
address it represents. */
|
||
CORE_ADDR
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unsigned_pointer_to_address (struct type *type, const void *buf)
|
||
{
|
||
return extract_address (buf, TYPE_LENGTH (type));
|
||
}
|
||
|
||
CORE_ADDR
|
||
signed_pointer_to_address (struct type *type, const void *buf)
|
||
{
|
||
return extract_signed_integer (buf, TYPE_LENGTH (type));
|
||
}
|
||
|
||
/* Given an address, store it as a pointer of type TYPE in target
|
||
format in BUF. */
|
||
void
|
||
unsigned_address_to_pointer (struct type *type, void *buf, CORE_ADDR addr)
|
||
{
|
||
store_address (buf, TYPE_LENGTH (type), addr);
|
||
}
|
||
|
||
void
|
||
address_to_signed_pointer (struct type *type, void *buf, CORE_ADDR addr)
|
||
{
|
||
store_signed_integer (buf, TYPE_LENGTH (type), addr);
|
||
}
|
||
|
||
/* Will calling read_var_value or locate_var_value on SYM end
|
||
up caring what frame it is being evaluated relative to? SYM must
|
||
be non-NULL. */
|
||
int
|
||
symbol_read_needs_frame (struct symbol *sym)
|
||
{
|
||
switch (SYMBOL_CLASS (sym))
|
||
{
|
||
/* All cases listed explicitly so that gcc -Wall will detect it if
|
||
we failed to consider one. */
|
||
case LOC_REGISTER:
|
||
case LOC_ARG:
|
||
case LOC_REF_ARG:
|
||
case LOC_REGPARM:
|
||
case LOC_REGPARM_ADDR:
|
||
case LOC_LOCAL:
|
||
case LOC_LOCAL_ARG:
|
||
case LOC_BASEREG:
|
||
case LOC_BASEREG_ARG:
|
||
case LOC_HP_THREAD_LOCAL_STATIC:
|
||
return 1;
|
||
|
||
case LOC_UNDEF:
|
||
case LOC_CONST:
|
||
case LOC_STATIC:
|
||
case LOC_INDIRECT:
|
||
case LOC_TYPEDEF:
|
||
|
||
case LOC_LABEL:
|
||
/* Getting the address of a label can be done independently of the block,
|
||
even if some *uses* of that address wouldn't work so well without
|
||
the right frame. */
|
||
|
||
case LOC_BLOCK:
|
||
case LOC_CONST_BYTES:
|
||
case LOC_UNRESOLVED:
|
||
case LOC_OPTIMIZED_OUT:
|
||
return 0;
|
||
}
|
||
return 1;
|
||
}
|
||
|
||
/* Given a struct symbol for a variable,
|
||
and a stack frame id, read the value of the variable
|
||
and return a (pointer to a) struct value containing the value.
|
||
If the variable cannot be found, return a zero pointer.
|
||
If FRAME is NULL, use the deprecated_selected_frame. */
|
||
|
||
struct value *
|
||
read_var_value (register struct symbol *var, struct frame_info *frame)
|
||
{
|
||
register struct value *v;
|
||
struct type *type = SYMBOL_TYPE (var);
|
||
CORE_ADDR addr;
|
||
register int len;
|
||
|
||
v = allocate_value (type);
|
||
VALUE_LVAL (v) = lval_memory; /* The most likely possibility. */
|
||
VALUE_BFD_SECTION (v) = SYMBOL_BFD_SECTION (var);
|
||
|
||
len = TYPE_LENGTH (type);
|
||
|
||
if (frame == NULL)
|
||
frame = deprecated_selected_frame;
|
||
|
||
switch (SYMBOL_CLASS (var))
|
||
{
|
||
case LOC_CONST:
|
||
/* Put the constant back in target format. */
|
||
store_signed_integer (VALUE_CONTENTS_RAW (v), len,
|
||
(LONGEST) SYMBOL_VALUE (var));
|
||
VALUE_LVAL (v) = not_lval;
|
||
return v;
|
||
|
||
case LOC_LABEL:
|
||
/* Put the constant back in target format. */
|
||
if (overlay_debugging)
|
||
{
|
||
CORE_ADDR addr
|
||
= symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var),
|
||
SYMBOL_BFD_SECTION (var));
|
||
store_typed_address (VALUE_CONTENTS_RAW (v), type, addr);
|
||
}
|
||
else
|
||
store_typed_address (VALUE_CONTENTS_RAW (v), type,
|
||
SYMBOL_VALUE_ADDRESS (var));
|
||
VALUE_LVAL (v) = not_lval;
|
||
return v;
|
||
|
||
case LOC_CONST_BYTES:
|
||
{
|
||
char *bytes_addr;
|
||
bytes_addr = SYMBOL_VALUE_BYTES (var);
|
||
memcpy (VALUE_CONTENTS_RAW (v), bytes_addr, len);
|
||
VALUE_LVAL (v) = not_lval;
|
||
return v;
|
||
}
|
||
|
||
case LOC_STATIC:
|
||
if (overlay_debugging)
|
||
addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var),
|
||
SYMBOL_BFD_SECTION (var));
|
||
else
|
||
addr = SYMBOL_VALUE_ADDRESS (var);
|
||
break;
|
||
|
||
case LOC_INDIRECT:
|
||
{
|
||
/* The import slot does not have a real address in it from the
|
||
dynamic loader (dld.sl on HP-UX), if the target hasn't
|
||
begun execution yet, so check for that. */
|
||
CORE_ADDR locaddr;
|
||
struct value *loc;
|
||
if (!target_has_execution)
|
||
error ("\
|
||
Attempt to access variable defined in different shared object or load module when\n\
|
||
addresses have not been bound by the dynamic loader. Try again when executable is running.");
|
||
|
||
locaddr = SYMBOL_VALUE_ADDRESS (var);
|
||
loc = value_at (lookup_pointer_type (type), locaddr, NULL);
|
||
addr = value_as_address (loc);
|
||
}
|
||
|
||
case LOC_ARG:
|
||
if (frame == NULL)
|
||
return 0;
|
||
addr = FRAME_ARGS_ADDRESS (frame);
|
||
if (!addr)
|
||
return 0;
|
||
addr += SYMBOL_VALUE (var);
|
||
break;
|
||
|
||
case LOC_REF_ARG:
|
||
{
|
||
struct value *ref;
|
||
CORE_ADDR argref;
|
||
if (frame == NULL)
|
||
return 0;
|
||
argref = FRAME_ARGS_ADDRESS (frame);
|
||
if (!argref)
|
||
return 0;
|
||
argref += SYMBOL_VALUE (var);
|
||
ref = value_at (lookup_pointer_type (type), argref, NULL);
|
||
addr = value_as_address (ref);
|
||
break;
|
||
}
|
||
|
||
case LOC_LOCAL:
|
||
case LOC_LOCAL_ARG:
|
||
if (frame == NULL)
|
||
return 0;
|
||
addr = FRAME_LOCALS_ADDRESS (frame);
|
||
addr += SYMBOL_VALUE (var);
|
||
break;
|
||
|
||
case LOC_BASEREG:
|
||
case LOC_BASEREG_ARG:
|
||
case LOC_HP_THREAD_LOCAL_STATIC:
|
||
{
|
||
struct value *regval;
|
||
|
||
regval = value_from_register (lookup_pointer_type (type),
|
||
SYMBOL_BASEREG (var), frame);
|
||
if (regval == NULL)
|
||
error ("Value of base register not available.");
|
||
addr = value_as_address (regval);
|
||
addr += SYMBOL_VALUE (var);
|
||
break;
|
||
}
|
||
|
||
case LOC_THREAD_LOCAL_STATIC:
|
||
{
|
||
if (target_get_thread_local_address_p ())
|
||
addr = target_get_thread_local_address (inferior_ptid,
|
||
SYMBOL_OBJFILE (var),
|
||
SYMBOL_VALUE_ADDRESS (var));
|
||
/* It wouldn't be wrong here to try a gdbarch method, too;
|
||
finding TLS is an ABI-specific thing. But we don't do that
|
||
yet. */
|
||
else
|
||
error ("Cannot find thread-local variables on this target");
|
||
break;
|
||
}
|
||
|
||
case LOC_TYPEDEF:
|
||
error ("Cannot look up value of a typedef");
|
||
break;
|
||
|
||
case LOC_BLOCK:
|
||
if (overlay_debugging)
|
||
VALUE_ADDRESS (v) = symbol_overlayed_address
|
||
(BLOCK_START (SYMBOL_BLOCK_VALUE (var)), SYMBOL_BFD_SECTION (var));
|
||
else
|
||
VALUE_ADDRESS (v) = BLOCK_START (SYMBOL_BLOCK_VALUE (var));
|
||
return v;
|
||
|
||
case LOC_REGISTER:
|
||
case LOC_REGPARM:
|
||
case LOC_REGPARM_ADDR:
|
||
{
|
||
struct block *b;
|
||
int regno = SYMBOL_VALUE (var);
|
||
struct value *regval;
|
||
|
||
if (frame == NULL)
|
||
return 0;
|
||
b = get_frame_block (frame, 0);
|
||
|
||
if (SYMBOL_CLASS (var) == LOC_REGPARM_ADDR)
|
||
{
|
||
regval = value_from_register (lookup_pointer_type (type),
|
||
regno,
|
||
frame);
|
||
|
||
if (regval == NULL)
|
||
error ("Value of register variable not available.");
|
||
|
||
addr = value_as_address (regval);
|
||
VALUE_LVAL (v) = lval_memory;
|
||
}
|
||
else
|
||
{
|
||
regval = value_from_register (type, regno, frame);
|
||
|
||
if (regval == NULL)
|
||
error ("Value of register variable not available.");
|
||
return regval;
|
||
}
|
||
}
|
||
break;
|
||
|
||
case LOC_UNRESOLVED:
|
||
{
|
||
struct minimal_symbol *msym;
|
||
|
||
msym = lookup_minimal_symbol (SYMBOL_NAME (var), NULL, NULL);
|
||
if (msym == NULL)
|
||
return 0;
|
||
if (overlay_debugging)
|
||
addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (msym),
|
||
SYMBOL_BFD_SECTION (msym));
|
||
else
|
||
addr = SYMBOL_VALUE_ADDRESS (msym);
|
||
}
|
||
break;
|
||
|
||
case LOC_OPTIMIZED_OUT:
|
||
VALUE_LVAL (v) = not_lval;
|
||
VALUE_OPTIMIZED_OUT (v) = 1;
|
||
return v;
|
||
|
||
default:
|
||
error ("Cannot look up value of a botched symbol.");
|
||
break;
|
||
}
|
||
|
||
VALUE_ADDRESS (v) = addr;
|
||
VALUE_LAZY (v) = 1;
|
||
return v;
|
||
}
|
||
|
||
/* Return a value of type TYPE, stored in register REGNUM, in frame
|
||
FRAME.
|
||
|
||
NOTE: returns NULL if register value is not available.
|
||
Caller will check return value or die! */
|
||
|
||
struct value *
|
||
value_from_register (struct type *type, int regnum, struct frame_info *frame)
|
||
{
|
||
char *raw_buffer = (char*) alloca (MAX_REGISTER_RAW_SIZE);
|
||
CORE_ADDR addr;
|
||
int optim;
|
||
struct value *v = allocate_value (type);
|
||
char *value_bytes = 0;
|
||
int value_bytes_copied = 0;
|
||
int num_storage_locs;
|
||
enum lval_type lval;
|
||
int len;
|
||
|
||
CHECK_TYPEDEF (type);
|
||
len = TYPE_LENGTH (type);
|
||
|
||
VALUE_REGNO (v) = regnum;
|
||
|
||
num_storage_locs = (len > REGISTER_VIRTUAL_SIZE (regnum) ?
|
||
((len - 1) / REGISTER_RAW_SIZE (regnum)) + 1 :
|
||
1);
|
||
|
||
if (num_storage_locs > 1
|
||
#ifdef GDB_TARGET_IS_H8500
|
||
|| TYPE_CODE (type) == TYPE_CODE_PTR
|
||
#endif
|
||
)
|
||
{
|
||
/* Value spread across multiple storage locations. */
|
||
|
||
int local_regnum;
|
||
int mem_stor = 0, reg_stor = 0;
|
||
int mem_tracking = 1;
|
||
CORE_ADDR last_addr = 0;
|
||
CORE_ADDR first_addr = 0;
|
||
|
||
value_bytes = (char *) alloca (len + MAX_REGISTER_RAW_SIZE);
|
||
|
||
/* Copy all of the data out, whereever it may be. */
|
||
|
||
#ifdef GDB_TARGET_IS_H8500
|
||
/* This piece of hideosity is required because the H8500 treats registers
|
||
differently depending upon whether they are used as pointers or not. As a
|
||
pointer, a register needs to have a page register tacked onto the front.
|
||
An alternate way to do this would be to have gcc output different register
|
||
numbers for the pointer & non-pointer form of the register. But, it
|
||
doesn't, so we're stuck with this. */
|
||
|
||
if (TYPE_CODE (type) == TYPE_CODE_PTR
|
||
&& len > 2)
|
||
{
|
||
int page_regnum;
|
||
|
||
switch (regnum)
|
||
{
|
||
case R0_REGNUM:
|
||
case R1_REGNUM:
|
||
case R2_REGNUM:
|
||
case R3_REGNUM:
|
||
page_regnum = SEG_D_REGNUM;
|
||
break;
|
||
case R4_REGNUM:
|
||
case R5_REGNUM:
|
||
page_regnum = SEG_E_REGNUM;
|
||
break;
|
||
case R6_REGNUM:
|
||
case R7_REGNUM:
|
||
page_regnum = SEG_T_REGNUM;
|
||
break;
|
||
}
|
||
|
||
value_bytes[0] = 0;
|
||
get_saved_register (value_bytes + 1,
|
||
&optim,
|
||
&addr,
|
||
frame,
|
||
page_regnum,
|
||
&lval);
|
||
|
||
if (register_cached (page_regnum) == -1)
|
||
return NULL; /* register value not available */
|
||
|
||
if (lval == lval_register)
|
||
reg_stor++;
|
||
else
|
||
mem_stor++;
|
||
first_addr = addr;
|
||
last_addr = addr;
|
||
|
||
get_saved_register (value_bytes + 2,
|
||
&optim,
|
||
&addr,
|
||
frame,
|
||
regnum,
|
||
&lval);
|
||
|
||
if (register_cached (regnum) == -1)
|
||
return NULL; /* register value not available */
|
||
|
||
if (lval == lval_register)
|
||
reg_stor++;
|
||
else
|
||
{
|
||
mem_stor++;
|
||
mem_tracking = mem_tracking && (addr == last_addr);
|
||
}
|
||
last_addr = addr;
|
||
}
|
||
else
|
||
#endif /* GDB_TARGET_IS_H8500 */
|
||
for (local_regnum = regnum;
|
||
value_bytes_copied < len;
|
||
(value_bytes_copied += REGISTER_RAW_SIZE (local_regnum),
|
||
++local_regnum))
|
||
{
|
||
get_saved_register (value_bytes + value_bytes_copied,
|
||
&optim,
|
||
&addr,
|
||
frame,
|
||
local_regnum,
|
||
&lval);
|
||
|
||
if (register_cached (local_regnum) == -1)
|
||
return NULL; /* register value not available */
|
||
|
||
if (regnum == local_regnum)
|
||
first_addr = addr;
|
||
if (lval == lval_register)
|
||
reg_stor++;
|
||
else
|
||
{
|
||
mem_stor++;
|
||
|
||
mem_tracking =
|
||
(mem_tracking
|
||
&& (regnum == local_regnum
|
||
|| addr == last_addr));
|
||
}
|
||
last_addr = addr;
|
||
}
|
||
|
||
if ((reg_stor && mem_stor)
|
||
|| (mem_stor && !mem_tracking))
|
||
/* Mixed storage; all of the hassle we just went through was
|
||
for some good purpose. */
|
||
{
|
||
VALUE_LVAL (v) = lval_reg_frame_relative;
|
||
VALUE_FRAME (v) = get_frame_base (frame);
|
||
VALUE_FRAME_REGNUM (v) = regnum;
|
||
}
|
||
else if (mem_stor)
|
||
{
|
||
VALUE_LVAL (v) = lval_memory;
|
||
VALUE_ADDRESS (v) = first_addr;
|
||
}
|
||
else if (reg_stor)
|
||
{
|
||
VALUE_LVAL (v) = lval_register;
|
||
VALUE_ADDRESS (v) = first_addr;
|
||
}
|
||
else
|
||
internal_error (__FILE__, __LINE__,
|
||
"value_from_register: Value not stored anywhere!");
|
||
|
||
VALUE_OPTIMIZED_OUT (v) = optim;
|
||
|
||
/* Any structure stored in more than one register will always be
|
||
an integral number of registers. Otherwise, you'd need to do
|
||
some fiddling with the last register copied here for little
|
||
endian machines. */
|
||
|
||
/* Copy into the contents section of the value. */
|
||
memcpy (VALUE_CONTENTS_RAW (v), value_bytes, len);
|
||
|
||
/* Finally do any conversion necessary when extracting this
|
||
type from more than one register. */
|
||
#ifdef REGISTER_CONVERT_TO_TYPE
|
||
REGISTER_CONVERT_TO_TYPE (regnum, type, VALUE_CONTENTS_RAW (v));
|
||
#endif
|
||
return v;
|
||
}
|
||
|
||
/* Data is completely contained within a single register. Locate the
|
||
register's contents in a real register or in core;
|
||
read the data in raw format. */
|
||
|
||
get_saved_register (raw_buffer, &optim, &addr, frame, regnum, &lval);
|
||
|
||
if (register_cached (regnum) == -1)
|
||
return NULL; /* register value not available */
|
||
|
||
VALUE_OPTIMIZED_OUT (v) = optim;
|
||
VALUE_LVAL (v) = lval;
|
||
VALUE_ADDRESS (v) = addr;
|
||
|
||
/* Convert the raw register to the corresponding data value's memory
|
||
format, if necessary. */
|
||
|
||
if (CONVERT_REGISTER_P (regnum))
|
||
{
|
||
REGISTER_TO_VALUE (regnum, type, raw_buffer, VALUE_CONTENTS_RAW (v));
|
||
}
|
||
else
|
||
{
|
||
/* Raw and virtual formats are the same for this register. */
|
||
|
||
if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG && len < REGISTER_RAW_SIZE (regnum))
|
||
{
|
||
/* Big-endian, and we want less than full size. */
|
||
VALUE_OFFSET (v) = REGISTER_RAW_SIZE (regnum) - len;
|
||
}
|
||
|
||
memcpy (VALUE_CONTENTS_RAW (v), raw_buffer + VALUE_OFFSET (v), len);
|
||
}
|
||
|
||
return v;
|
||
}
|
||
|
||
/* Given a struct symbol for a variable or function,
|
||
and a stack frame id,
|
||
return a (pointer to a) struct value containing the properly typed
|
||
address. */
|
||
|
||
struct value *
|
||
locate_var_value (register struct symbol *var, struct frame_info *frame)
|
||
{
|
||
CORE_ADDR addr = 0;
|
||
struct type *type = SYMBOL_TYPE (var);
|
||
struct value *lazy_value;
|
||
|
||
/* Evaluate it first; if the result is a memory address, we're fine.
|
||
Lazy evaluation pays off here. */
|
||
|
||
lazy_value = read_var_value (var, frame);
|
||
if (lazy_value == 0)
|
||
error ("Address of \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var));
|
||
|
||
if (VALUE_LAZY (lazy_value)
|
||
|| TYPE_CODE (type) == TYPE_CODE_FUNC)
|
||
{
|
||
struct value *val;
|
||
|
||
addr = VALUE_ADDRESS (lazy_value);
|
||
val = value_from_pointer (lookup_pointer_type (type), addr);
|
||
VALUE_BFD_SECTION (val) = VALUE_BFD_SECTION (lazy_value);
|
||
return val;
|
||
}
|
||
|
||
/* Not a memory address; check what the problem was. */
|
||
switch (VALUE_LVAL (lazy_value))
|
||
{
|
||
case lval_register:
|
||
gdb_assert (REGISTER_NAME (VALUE_REGNO (lazy_value)) != NULL
|
||
&& *REGISTER_NAME (VALUE_REGNO (lazy_value)) != '\0');
|
||
error("Address requested for identifier "
|
||
"\"%s\" which is in register $%s",
|
||
SYMBOL_SOURCE_NAME (var),
|
||
REGISTER_NAME (VALUE_REGNO (lazy_value)));
|
||
break;
|
||
|
||
case lval_reg_frame_relative:
|
||
gdb_assert (REGISTER_NAME (VALUE_FRAME_REGNUM (lazy_value)) != NULL
|
||
&& *REGISTER_NAME (VALUE_FRAME_REGNUM (lazy_value)) != '\0');
|
||
error("Address requested for identifier "
|
||
"\"%s\" which is in frame register $%s",
|
||
SYMBOL_SOURCE_NAME (var),
|
||
REGISTER_NAME (VALUE_FRAME_REGNUM (lazy_value)));
|
||
break;
|
||
|
||
default:
|
||
error ("Can't take address of \"%s\" which isn't an lvalue.",
|
||
SYMBOL_SOURCE_NAME (var));
|
||
break;
|
||
}
|
||
return 0; /* For lint -- never reached */
|
||
}
|