795 lines
22 KiB
C
795 lines
22 KiB
C
/* Find a variable's value in memory, for GDB, the GNU debugger.
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Copyright (C) 1986-2001, 2003-2005, 2007-2012 Free Software
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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 3 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, see <http://www.gnu.org/licenses/>. */
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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 "user-regs.h"
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#include "block.h"
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#include "objfiles.h"
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#include "language.h"
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/* Basic byte-swapping routines. All 'extract' functions return a
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host-format integer from a target-format integer at ADDR which is
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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 gdb_byte *addr, int len,
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enum bfd_endian byte_order)
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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 (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 gdb_byte *addr, int len,
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enum bfd_endian byte_order)
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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 (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 gdb_byte *addr, int orig_len,
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enum bfd_endian byte_order, LONGEST *pval)
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{
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const gdb_byte *p;
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const gdb_byte *first_addr;
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int len;
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len = orig_len;
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if (byte_order == BFD_ENDIAN_BIG)
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{
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for (p = addr;
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len > (int) sizeof (LONGEST) && p < 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 = addr;
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for (p = addr + orig_len - 1;
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len > (int) sizeof (LONGEST) && p >= 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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byte_order);
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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 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 gdb_byte *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 gdbarch_pointer_to_address (get_type_arch (type), type, buf);
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}
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/* All 'store' functions accept a host-format integer and store a
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target-format integer at ADDR which is LEN bytes long. */
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void
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store_signed_integer (gdb_byte *addr, int len,
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enum bfd_endian byte_order, LONGEST val)
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{
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gdb_byte *p;
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gdb_byte *startaddr = addr;
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gdb_byte *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 (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 (gdb_byte *addr, int len,
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enum bfd_endian byte_order, 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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/* Start at the least significant end of the integer, and work towards
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the most significant. */
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if (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 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 (gdb_byte *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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gdbarch_address_to_pointer (get_type_arch (type), 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_type(). */
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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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struct gdbarch *gdbarch = get_frame_arch (frame);
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CORE_ADDR addr;
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int optim;
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int unavail;
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struct value *reg_val;
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int realnum;
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gdb_byte raw_buffer[MAX_REGISTER_SIZE];
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enum lval_type lval;
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/* User registers lie completely 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 >= gdbarch_num_regs (gdbarch)
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+ gdbarch_num_pseudo_regs (gdbarch))
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return value_of_user_reg (regnum, frame);
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frame_register (frame, regnum, &optim, &unavail,
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&lval, &addr, &realnum, raw_buffer);
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reg_val = allocate_value (register_type (gdbarch, regnum));
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if (!optim && !unavail)
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memcpy (value_contents_raw (reg_val), raw_buffer,
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register_size (gdbarch, regnum));
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else
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memset (value_contents_raw (reg_val), 0,
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register_size (gdbarch, regnum));
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VALUE_LVAL (reg_val) = lval;
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set_value_address (reg_val, addr);
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VALUE_REGNUM (reg_val) = regnum;
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set_value_optimized_out (reg_val, optim);
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if (unavail)
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mark_value_bytes_unavailable (reg_val, 0, register_size (gdbarch, regnum));
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VALUE_FRAME_ID (reg_val) = get_frame_id (frame);
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return reg_val;
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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_type(). The value is not fetched. */
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struct value *
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value_of_register_lazy (struct frame_info *frame, int regnum)
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{
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struct gdbarch *gdbarch = get_frame_arch (frame);
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struct value *reg_val;
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gdb_assert (regnum < (gdbarch_num_regs (gdbarch)
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+ gdbarch_num_pseudo_regs (gdbarch)));
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/* We should have a valid (i.e. non-sentinel) frame. */
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gdb_assert (frame_id_p (get_frame_id (frame)));
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reg_val = allocate_value_lazy (register_type (gdbarch, regnum));
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VALUE_LVAL (reg_val) = lval_register;
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VALUE_REGNUM (reg_val) = regnum;
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VALUE_FRAME_ID (reg_val) = get_frame_id (frame);
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return reg_val;
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}
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/* Given a pointer of type TYPE in target form in BUF, return the
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address it represents. */
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CORE_ADDR
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unsigned_pointer_to_address (struct gdbarch *gdbarch,
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struct type *type, const gdb_byte *buf)
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{
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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return extract_unsigned_integer (buf, TYPE_LENGTH (type), byte_order);
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}
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CORE_ADDR
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signed_pointer_to_address (struct gdbarch *gdbarch,
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struct type *type, const gdb_byte *buf)
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{
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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return extract_signed_integer (buf, TYPE_LENGTH (type), byte_order);
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}
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/* Given an address, store it as a pointer of type TYPE in target
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format in BUF. */
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void
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unsigned_address_to_pointer (struct gdbarch *gdbarch, struct type *type,
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gdb_byte *buf, CORE_ADDR addr)
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{
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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store_unsigned_integer (buf, TYPE_LENGTH (type), byte_order, addr);
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}
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void
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address_to_signed_pointer (struct gdbarch *gdbarch, struct type *type,
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gdb_byte *buf, CORE_ADDR addr)
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{
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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store_signed_integer (buf, TYPE_LENGTH (type), byte_order, addr);
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}
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/* Will calling read_var_value or locate_var_value on SYM end
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up caring what frame it is being evaluated relative to? SYM must
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||
be non-NULL. */
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int
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symbol_read_needs_frame (struct symbol *sym)
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||
{
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switch (SYMBOL_CLASS (sym))
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{
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||
/* All cases listed explicitly so that gcc -Wall will detect it if
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we failed to consider one. */
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case LOC_COMPUTED:
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||
/* FIXME: cagney/2004-01-26: It should be possible to
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unconditionally call the SYMBOL_COMPUTED_OPS method when available.
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Unfortunately DWARF 2 stores the frame-base (instead of the
|
||
function) location in a function's symbol. Oops! For the
|
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moment enable this when/where applicable. */
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return SYMBOL_COMPUTED_OPS (sym)->read_needs_frame (sym);
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|
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case LOC_REGISTER:
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case LOC_ARG:
|
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case LOC_REF_ARG:
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case LOC_REGPARM_ADDR:
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case LOC_LOCAL:
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return 1;
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||
|
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case LOC_UNDEF:
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||
case LOC_CONST:
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||
case LOC_STATIC:
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||
case LOC_TYPEDEF:
|
||
|
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case LOC_LABEL:
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||
/* 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. */
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||
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case LOC_BLOCK:
|
||
case LOC_CONST_BYTES:
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||
case LOC_UNRESOLVED:
|
||
case LOC_OPTIMIZED_OUT:
|
||
return 0;
|
||
}
|
||
return 1;
|
||
}
|
||
|
||
/* Private data to be used with minsym_lookup_iterator_cb. */
|
||
|
||
struct minsym_lookup_data
|
||
{
|
||
/* The name of the minimal symbol we are searching for. */
|
||
const char *name;
|
||
|
||
/* The field where the callback should store the minimal symbol
|
||
if found. It should be initialized to NULL before the search
|
||
is started. */
|
||
struct minimal_symbol *result;
|
||
};
|
||
|
||
/* A callback function for gdbarch_iterate_over_objfiles_in_search_order.
|
||
It searches by name for a minimal symbol within the given OBJFILE.
|
||
The arguments are passed via CB_DATA, which in reality is a pointer
|
||
to struct minsym_lookup_data. */
|
||
|
||
static int
|
||
minsym_lookup_iterator_cb (struct objfile *objfile, void *cb_data)
|
||
{
|
||
struct minsym_lookup_data *data = (struct minsym_lookup_data *) cb_data;
|
||
|
||
gdb_assert (data->result == NULL);
|
||
|
||
data->result = lookup_minimal_symbol (data->name, NULL, objfile);
|
||
|
||
/* The iterator should stop iff a match was found. */
|
||
return (data->result != NULL);
|
||
}
|
||
|
||
/* A default implementation for the "la_read_var_value" hook in
|
||
the language vector which should work in most situations. */
|
||
|
||
struct value *
|
||
default_read_var_value (struct symbol *var, struct frame_info *frame)
|
||
{
|
||
struct value *v;
|
||
struct type *type = SYMBOL_TYPE (var);
|
||
CORE_ADDR addr;
|
||
|
||
/* Call check_typedef on our type to make sure that, if TYPE is
|
||
a TYPE_CODE_TYPEDEF, its length is set to the length of the target type
|
||
instead of zero. However, we do not replace the typedef type by the
|
||
target type, because we want to keep the typedef in order to be able to
|
||
set the returned value type description correctly. */
|
||
check_typedef (type);
|
||
|
||
if (symbol_read_needs_frame (var))
|
||
gdb_assert (frame);
|
||
|
||
switch (SYMBOL_CLASS (var))
|
||
{
|
||
case LOC_CONST:
|
||
/* Put the constant back in target format. */
|
||
v = allocate_value (type);
|
||
store_signed_integer (value_contents_raw (v), TYPE_LENGTH (type),
|
||
gdbarch_byte_order (get_type_arch (type)),
|
||
(LONGEST) SYMBOL_VALUE (var));
|
||
VALUE_LVAL (v) = not_lval;
|
||
return v;
|
||
|
||
case LOC_LABEL:
|
||
/* Put the constant back in target format. */
|
||
v = allocate_value (type);
|
||
if (overlay_debugging)
|
||
{
|
||
CORE_ADDR addr
|
||
= symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var),
|
||
SYMBOL_OBJ_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:
|
||
v = allocate_value (type);
|
||
memcpy (value_contents_raw (v), SYMBOL_VALUE_BYTES (var),
|
||
TYPE_LENGTH (type));
|
||
VALUE_LVAL (v) = not_lval;
|
||
return v;
|
||
|
||
case LOC_STATIC:
|
||
v = allocate_value_lazy (type);
|
||
if (overlay_debugging)
|
||
addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var),
|
||
SYMBOL_OBJ_SECTION (var));
|
||
else
|
||
addr = SYMBOL_VALUE_ADDRESS (var);
|
||
break;
|
||
|
||
case LOC_ARG:
|
||
addr = get_frame_args_address (frame);
|
||
if (!addr)
|
||
error (_("Unknown argument list address for `%s'."),
|
||
SYMBOL_PRINT_NAME (var));
|
||
addr += SYMBOL_VALUE (var);
|
||
v = allocate_value_lazy (type);
|
||
break;
|
||
|
||
case LOC_REF_ARG:
|
||
{
|
||
struct value *ref;
|
||
CORE_ADDR argref;
|
||
|
||
argref = get_frame_args_address (frame);
|
||
if (!argref)
|
||
error (_("Unknown argument list address for `%s'."),
|
||
SYMBOL_PRINT_NAME (var));
|
||
argref += SYMBOL_VALUE (var);
|
||
ref = value_at (lookup_pointer_type (type), argref);
|
||
addr = value_as_address (ref);
|
||
v = allocate_value_lazy (type);
|
||
break;
|
||
}
|
||
|
||
case LOC_LOCAL:
|
||
addr = get_frame_locals_address (frame);
|
||
addr += SYMBOL_VALUE (var);
|
||
v = allocate_value_lazy (type);
|
||
break;
|
||
|
||
case LOC_TYPEDEF:
|
||
error (_("Cannot look up value of a typedef `%s'."),
|
||
SYMBOL_PRINT_NAME (var));
|
||
break;
|
||
|
||
case LOC_BLOCK:
|
||
v = allocate_value_lazy (type);
|
||
if (overlay_debugging)
|
||
addr = symbol_overlayed_address
|
||
(BLOCK_START (SYMBOL_BLOCK_VALUE (var)), SYMBOL_OBJ_SECTION (var));
|
||
else
|
||
addr = BLOCK_START (SYMBOL_BLOCK_VALUE (var));
|
||
break;
|
||
|
||
case LOC_REGISTER:
|
||
case LOC_REGPARM_ADDR:
|
||
{
|
||
int regno = SYMBOL_REGISTER_OPS (var)
|
||
->register_number (var, get_frame_arch (frame));
|
||
struct value *regval;
|
||
|
||
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 for `%s'."),
|
||
SYMBOL_PRINT_NAME (var));
|
||
|
||
addr = value_as_address (regval);
|
||
v = allocate_value_lazy (type);
|
||
}
|
||
else
|
||
{
|
||
regval = value_from_register (type, regno, frame);
|
||
|
||
if (regval == NULL)
|
||
error (_("Value of register variable not available for `%s'."),
|
||
SYMBOL_PRINT_NAME (var));
|
||
return regval;
|
||
}
|
||
}
|
||
break;
|
||
|
||
case LOC_COMPUTED:
|
||
/* FIXME: cagney/2004-01-26: It should be possible to
|
||
unconditionally call the SYMBOL_COMPUTED_OPS method when available.
|
||
Unfortunately DWARF 2 stores the frame-base (instead of the
|
||
function) location in a function's symbol. Oops! For the
|
||
moment enable this when/where applicable. */
|
||
return SYMBOL_COMPUTED_OPS (var)->read_variable (var, frame);
|
||
|
||
case LOC_UNRESOLVED:
|
||
{
|
||
struct minsym_lookup_data lookup_data;
|
||
struct minimal_symbol *msym;
|
||
struct obj_section *obj_section;
|
||
|
||
memset (&lookup_data, 0, sizeof (lookup_data));
|
||
lookup_data.name = SYMBOL_LINKAGE_NAME (var);
|
||
|
||
gdbarch_iterate_over_objfiles_in_search_order
|
||
(get_objfile_arch (SYMBOL_SYMTAB (var)->objfile),
|
||
minsym_lookup_iterator_cb, &lookup_data,
|
||
SYMBOL_SYMTAB (var)->objfile);
|
||
msym = lookup_data.result;
|
||
|
||
if (msym == NULL)
|
||
error (_("No global symbol \"%s\"."), SYMBOL_LINKAGE_NAME (var));
|
||
if (overlay_debugging)
|
||
addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (msym),
|
||
SYMBOL_OBJ_SECTION (msym));
|
||
else
|
||
addr = SYMBOL_VALUE_ADDRESS (msym);
|
||
|
||
obj_section = SYMBOL_OBJ_SECTION (msym);
|
||
if (obj_section
|
||
&& (obj_section->the_bfd_section->flags & SEC_THREAD_LOCAL) != 0)
|
||
addr = target_translate_tls_address (obj_section->objfile, addr);
|
||
v = allocate_value_lazy (type);
|
||
}
|
||
break;
|
||
|
||
case LOC_OPTIMIZED_OUT:
|
||
return allocate_optimized_out_value (type);
|
||
|
||
default:
|
||
error (_("Cannot look up value of a botched symbol `%s'."),
|
||
SYMBOL_PRINT_NAME (var));
|
||
break;
|
||
}
|
||
|
||
VALUE_LVAL (v) = lval_memory;
|
||
set_value_address (v, addr);
|
||
return v;
|
||
}
|
||
|
||
/* Calls VAR's language la_read_var_value hook with the given arguments. */
|
||
|
||
struct value *
|
||
read_var_value (struct symbol *var, struct frame_info *frame)
|
||
{
|
||
const struct language_defn *lang = language_def (SYMBOL_LANGUAGE (var));
|
||
|
||
gdb_assert (lang != NULL);
|
||
gdb_assert (lang->la_read_var_value != NULL);
|
||
|
||
return lang->la_read_var_value (var, frame);
|
||
}
|
||
|
||
/* Install default attributes for register values. */
|
||
|
||
struct value *
|
||
default_value_from_register (struct type *type, int regnum,
|
||
struct frame_info *frame)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (frame);
|
||
int len = TYPE_LENGTH (type);
|
||
struct value *value = allocate_value (type);
|
||
|
||
VALUE_LVAL (value) = lval_register;
|
||
VALUE_FRAME_ID (value) = get_frame_id (frame);
|
||
VALUE_REGNUM (value) = regnum;
|
||
|
||
/* Any structure stored in more than one register will always be
|
||
an integral number of registers. Otherwise, you need to do
|
||
some fiddling with the last register copied here for little
|
||
endian machines. */
|
||
if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG
|
||
&& len < register_size (gdbarch, regnum))
|
||
/* Big-endian, and we want less than full size. */
|
||
set_value_offset (value, register_size (gdbarch, regnum) - len);
|
||
else
|
||
set_value_offset (value, 0);
|
||
|
||
return value;
|
||
}
|
||
|
||
/* VALUE must be an lval_register value. If regnum is the value's
|
||
associated register number, and len the length of the values type,
|
||
read one or more registers in FRAME, starting with register REGNUM,
|
||
until we've read LEN bytes.
|
||
|
||
If any of the registers we try to read are optimized out, then mark the
|
||
complete resulting value as optimized out. */
|
||
|
||
void
|
||
read_frame_register_value (struct value *value, struct frame_info *frame)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (frame);
|
||
int offset = 0;
|
||
int reg_offset = value_offset (value);
|
||
int regnum = VALUE_REGNUM (value);
|
||
int len = TYPE_LENGTH (check_typedef (value_type (value)));
|
||
|
||
gdb_assert (VALUE_LVAL (value) == lval_register);
|
||
|
||
/* Skip registers wholly inside of REG_OFFSET. */
|
||
while (reg_offset >= register_size (gdbarch, regnum))
|
||
{
|
||
reg_offset -= register_size (gdbarch, regnum);
|
||
regnum++;
|
||
}
|
||
|
||
/* Copy the data. */
|
||
while (len > 0)
|
||
{
|
||
struct value *regval = get_frame_register_value (frame, regnum);
|
||
int reg_len = TYPE_LENGTH (value_type (regval)) - reg_offset;
|
||
|
||
if (value_optimized_out (regval))
|
||
{
|
||
set_value_optimized_out (value, 1);
|
||
break;
|
||
}
|
||
|
||
/* If the register length is larger than the number of bytes
|
||
remaining to copy, then only copy the appropriate bytes. */
|
||
if (reg_len > len)
|
||
reg_len = len;
|
||
|
||
value_contents_copy (value, offset, regval, reg_offset, reg_len);
|
||
|
||
offset += reg_len;
|
||
len -= reg_len;
|
||
reg_offset = 0;
|
||
regnum++;
|
||
}
|
||
}
|
||
|
||
/* Return a value of type TYPE, stored in register REGNUM, in frame FRAME. */
|
||
|
||
struct value *
|
||
value_from_register (struct type *type, int regnum, struct frame_info *frame)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (frame);
|
||
struct type *type1 = check_typedef (type);
|
||
struct value *v;
|
||
|
||
if (gdbarch_convert_register_p (gdbarch, regnum, type1))
|
||
{
|
||
int optim, unavail, ok;
|
||
|
||
/* The ISA/ABI need to something weird when obtaining the
|
||
specified value from this register. It might need to
|
||
re-order non-adjacent, starting with REGNUM (see MIPS and
|
||
i386). It might need to convert the [float] register into
|
||
the corresponding [integer] type (see Alpha). The assumption
|
||
is that gdbarch_register_to_value populates the entire value
|
||
including the location. */
|
||
v = allocate_value (type);
|
||
VALUE_LVAL (v) = lval_register;
|
||
VALUE_FRAME_ID (v) = get_frame_id (frame);
|
||
VALUE_REGNUM (v) = regnum;
|
||
ok = gdbarch_register_to_value (gdbarch, frame, regnum, type1,
|
||
value_contents_raw (v), &optim,
|
||
&unavail);
|
||
|
||
if (!ok)
|
||
{
|
||
if (optim)
|
||
set_value_optimized_out (v, 1);
|
||
if (unavail)
|
||
mark_value_bytes_unavailable (v, 0, TYPE_LENGTH (type));
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* Construct the value. */
|
||
v = gdbarch_value_from_register (gdbarch, type, regnum, frame);
|
||
|
||
/* Get the data. */
|
||
read_frame_register_value (v, frame);
|
||
}
|
||
|
||
return v;
|
||
}
|
||
|
||
/* Return contents of register REGNUM in frame FRAME as address,
|
||
interpreted as value of type TYPE. Will abort if register
|
||
value is not available. */
|
||
|
||
CORE_ADDR
|
||
address_from_register (struct type *type, int regnum, struct frame_info *frame)
|
||
{
|
||
struct value *value;
|
||
CORE_ADDR result;
|
||
|
||
value = value_from_register (type, regnum, frame);
|
||
gdb_assert (value);
|
||
|
||
result = value_as_address (value);
|
||
release_value (value);
|
||
value_free (value);
|
||
|
||
return result;
|
||
}
|
||
|