/* Low level packing and unpacking of values for GDB, the GNU Debugger.
- Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
- 1996, 1997, 1998, 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
- 2009, 2010 Free Software Foundation, Inc.
+ Copyright (C) 1986-2014 Free Software Foundation, Inc.
This file is part of GDB.
#include "defs.h"
#include "arch-utils.h"
-#include "gdb_string.h"
+#include <string.h>
#include "symtab.h"
#include "gdbtypes.h"
#include "value.h"
#include "objfiles.h"
#include "valprint.h"
#include "cli/cli-decode.h"
+#include "exceptions.h"
+#include "extension.h"
+#include <ctype.h>
+#include "tracepoint.h"
+#include "cp-abi.h"
+#include "user-regs.h"
-#include "python/python.h"
-
-/* Prototypes for exported functions. */
+/* Prototypes for exported functions. */
void _initialize_values (void);
void *cookie;
};
+/* Defines an [OFFSET, OFFSET + LENGTH) range. */
+
+struct range
+{
+ /* Lowest offset in the range. */
+ int offset;
+
+ /* Length of the range. */
+ int length;
+};
+
+typedef struct range range_s;
+
+DEF_VEC_O(range_s);
+
+/* Returns true if the ranges defined by [offset1, offset1+len1) and
+ [offset2, offset2+len2) overlap. */
+
+static int
+ranges_overlap (int offset1, int len1,
+ int offset2, int len2)
+{
+ ULONGEST h, l;
+
+ l = max (offset1, offset2);
+ h = min (offset1 + len1, offset2 + len2);
+ return (l < h);
+}
+
+/* Returns true if the first argument is strictly less than the
+ second, useful for VEC_lower_bound. We keep ranges sorted by
+ offset and coalesce overlapping and contiguous ranges, so this just
+ compares the starting offset. */
+
+static int
+range_lessthan (const range_s *r1, const range_s *r2)
+{
+ return r1->offset < r2->offset;
+}
+
+/* Returns true if RANGES contains any range that overlaps [OFFSET,
+ OFFSET+LENGTH). */
+
+static int
+ranges_contain (VEC(range_s) *ranges, int offset, int length)
+{
+ range_s what;
+ int i;
+
+ what.offset = offset;
+ what.length = length;
+
+ /* We keep ranges sorted by offset and coalesce overlapping and
+ contiguous ranges, so to check if a range list contains a given
+ range, we can do a binary search for the position the given range
+ would be inserted if we only considered the starting OFFSET of
+ ranges. We call that position I. Since we also have LENGTH to
+ care for (this is a range afterall), we need to check if the
+ _previous_ range overlaps the I range. E.g.,
+
+ R
+ |---|
+ |---| |---| |------| ... |--|
+ 0 1 2 N
+
+ I=1
+
+ In the case above, the binary search would return `I=1', meaning,
+ this OFFSET should be inserted at position 1, and the current
+ position 1 should be pushed further (and before 2). But, `0'
+ overlaps with R.
+
+ Then we need to check if the I range overlaps the I range itself.
+ E.g.,
+
+ R
+ |---|
+ |---| |---| |-------| ... |--|
+ 0 1 2 N
+
+ I=1
+ */
+
+ i = VEC_lower_bound (range_s, ranges, &what, range_lessthan);
+
+ if (i > 0)
+ {
+ struct range *bef = VEC_index (range_s, ranges, i - 1);
+
+ if (ranges_overlap (bef->offset, bef->length, offset, length))
+ return 1;
+ }
+
+ if (i < VEC_length (range_s, ranges))
+ {
+ struct range *r = VEC_index (range_s, ranges, i);
+
+ if (ranges_overlap (r->offset, r->length, offset, length))
+ return 1;
+ }
+
+ return 0;
+}
+
static struct cmd_list_element *functionlist;
+/* Note that the fields in this structure are arranged to save a bit
+ of memory. */
+
struct value
{
/* Type of value; either not an lval, or one of the various
enum lval_type lval;
/* Is it modifiable? Only relevant if lval != not_lval. */
- int modifiable;
+ unsigned int modifiable : 1;
+
+ /* If zero, contents of this value are in the contents field. If
+ nonzero, contents are in inferior. If the lval field is lval_memory,
+ the contents are in inferior memory at location.address plus offset.
+ The lval field may also be lval_register.
+
+ WARNING: This field is used by the code which handles watchpoints
+ (see breakpoint.c) to decide whether a particular value can be
+ watched by hardware watchpoints. If the lazy flag is set for
+ some member of a value chain, it is assumed that this member of
+ the chain doesn't need to be watched as part of watching the
+ value itself. This is how GDB avoids watching the entire struct
+ or array when the user wants to watch a single struct member or
+ array element. If you ever change the way lazy flag is set and
+ reset, be sure to consider this use as well! */
+ unsigned int lazy : 1;
+
+ /* If nonzero, this is the value of a variable that does not
+ actually exist in the program. If nonzero, and LVAL is
+ lval_register, this is a register ($pc, $sp, etc., never a
+ program variable) that has not been saved in the frame. All
+ optimized-out values are treated pretty much the same, except
+ registers have a different string representation and related
+ error strings. */
+ unsigned int optimized_out : 1;
+
+ /* If value is a variable, is it initialized or not. */
+ unsigned int initialized : 1;
+
+ /* If value is from the stack. If this is set, read_stack will be
+ used instead of read_memory to enable extra caching. */
+ unsigned int stack : 1;
+
+ /* If the value has been released. */
+ unsigned int released : 1;
+
+ /* Register number if the value is from a register. */
+ short regnum;
/* Location of value (if lval). */
union
for them to use. */
struct
{
- struct lval_funcs *funcs; /* Functions to call. */
- void *closure; /* Closure for those functions to use. */
+ /* Functions to call. */
+ const struct lval_funcs *funcs;
+
+ /* Closure for those functions to use. */
+ void *closure;
} computed;
} location;
/* Only used for bitfields; position of start of field. For
gdbarch_bits_big_endian=0 targets, it is the position of the LSB. For
- gdbarch_bits_big_endian=1 targets, it is the position of the MSB. */
+ gdbarch_bits_big_endian=1 targets, it is the position of the MSB. */
int bitpos;
+ /* The number of references to this value. When a value is created,
+ the value chain holds a reference, so REFERENCE_COUNT is 1. If
+ release_value is called, this value is removed from the chain but
+ the caller of release_value now has a reference to this value.
+ The caller must arrange for a call to value_free later. */
+ int reference_count;
+
/* Only used for bitfields; the containing value. This allows a
single read from the target when displaying multiple
bitfields. */
taken off this list. */
struct value *next;
- /* Register number if the value is from a register. */
- short regnum;
+ /* Actual contents of the value. Target byte-order. NULL or not
+ valid if lazy is nonzero. */
+ gdb_byte *contents;
- /* If zero, contents of this value are in the contents field. If
- nonzero, contents are in inferior. If the lval field is lval_memory,
- the contents are in inferior memory at location.address plus offset.
- The lval field may also be lval_register.
+ /* Unavailable ranges in CONTENTS. We mark unavailable ranges,
+ rather than available, since the common and default case is for a
+ value to be available. This is filled in at value read time. The
+ unavailable ranges are tracked in bits. */
+ VEC(range_s) *unavailable;
+};
- WARNING: This field is used by the code which handles watchpoints
- (see breakpoint.c) to decide whether a particular value can be
- watched by hardware watchpoints. If the lazy flag is set for
- some member of a value chain, it is assumed that this member of
- the chain doesn't need to be watched as part of watching the
- value itself. This is how GDB avoids watching the entire struct
- or array when the user wants to watch a single struct member or
- array element. If you ever change the way lazy flag is set and
- reset, be sure to consider this use as well! */
- char lazy;
+int
+value_bits_available (const struct value *value, int offset, int length)
+{
+ gdb_assert (!value->lazy);
- /* If nonzero, this is the value of a variable which does not
- actually exist in the program. */
- char optimized_out;
+ return !ranges_contain (value->unavailable, offset, length);
+}
- /* If value is a variable, is it initialized or not. */
- int initialized;
+int
+value_bytes_available (const struct value *value, int offset, int length)
+{
+ return value_bits_available (value,
+ offset * TARGET_CHAR_BIT,
+ length * TARGET_CHAR_BIT);
+}
- /* If value is from the stack. If this is set, read_stack will be
- used instead of read_memory to enable extra caching. */
- int stack;
+int
+value_entirely_available (struct value *value)
+{
+ /* We can only tell whether the whole value is available when we try
+ to read it. */
+ if (value->lazy)
+ value_fetch_lazy (value);
- /* Actual contents of the value. Target byte-order. NULL or not
- valid if lazy is nonzero. */
- gdb_byte *contents;
+ if (VEC_empty (range_s, value->unavailable))
+ return 1;
+ return 0;
+}
- /* The number of references to this value. When a value is created,
- the value chain holds a reference, so REFERENCE_COUNT is 1. If
- release_value is called, this value is removed from the chain but
- the caller of release_value now has a reference to this value.
- The caller must arrange for a call to value_free later. */
- int reference_count;
-};
+int
+value_entirely_unavailable (struct value *value)
+{
+ /* We can only tell whether the whole value is available when we try
+ to read it. */
+ if (value->lazy)
+ value_fetch_lazy (value);
+
+ if (VEC_length (range_s, value->unavailable) == 1)
+ {
+ struct range *t = VEC_index (range_s, value->unavailable, 0);
+
+ if (t->offset == 0
+ && t->length == (TARGET_CHAR_BIT
+ * TYPE_LENGTH (value_enclosing_type (value))))
+ return 1;
+ }
+
+ return 0;
+}
+
+void
+mark_value_bits_unavailable (struct value *value, int offset, int length)
+{
+ range_s newr;
+ int i;
+
+ /* Insert the range sorted. If there's overlap or the new range
+ would be contiguous with an existing range, merge. */
+
+ newr.offset = offset;
+ newr.length = length;
+
+ /* Do a binary search for the position the given range would be
+ inserted if we only considered the starting OFFSET of ranges.
+ Call that position I. Since we also have LENGTH to care for
+ (this is a range afterall), we need to check if the _previous_
+ range overlaps the I range. E.g., calling R the new range:
+
+ #1 - overlaps with previous
+
+ R
+ |-...-|
+ |---| |---| |------| ... |--|
+ 0 1 2 N
+
+ I=1
+
+ In the case #1 above, the binary search would return `I=1',
+ meaning, this OFFSET should be inserted at position 1, and the
+ current position 1 should be pushed further (and become 2). But,
+ note that `0' overlaps with R, so we want to merge them.
+
+ A similar consideration needs to be taken if the new range would
+ be contiguous with the previous range:
+
+ #2 - contiguous with previous
+
+ R
+ |-...-|
+ |--| |---| |------| ... |--|
+ 0 1 2 N
+
+ I=1
+
+ If there's no overlap with the previous range, as in:
+
+ #3 - not overlapping and not contiguous
+
+ R
+ |-...-|
+ |--| |---| |------| ... |--|
+ 0 1 2 N
+
+ I=1
+
+ or if I is 0:
+
+ #4 - R is the range with lowest offset
+
+ R
+ |-...-|
+ |--| |---| |------| ... |--|
+ 0 1 2 N
+
+ I=0
+
+ ... we just push the new range to I.
+
+ All the 4 cases above need to consider that the new range may
+ also overlap several of the ranges that follow, or that R may be
+ contiguous with the following range, and merge. E.g.,
+
+ #5 - overlapping following ranges
+
+ R
+ |------------------------|
+ |--| |---| |------| ... |--|
+ 0 1 2 N
+
+ I=0
+
+ or:
+
+ R
+ |-------|
+ |--| |---| |------| ... |--|
+ 0 1 2 N
+
+ I=1
+
+ */
+
+ i = VEC_lower_bound (range_s, value->unavailable, &newr, range_lessthan);
+ if (i > 0)
+ {
+ struct range *bef = VEC_index (range_s, value->unavailable, i - 1);
+
+ if (ranges_overlap (bef->offset, bef->length, offset, length))
+ {
+ /* #1 */
+ ULONGEST l = min (bef->offset, offset);
+ ULONGEST h = max (bef->offset + bef->length, offset + length);
+
+ bef->offset = l;
+ bef->length = h - l;
+ i--;
+ }
+ else if (offset == bef->offset + bef->length)
+ {
+ /* #2 */
+ bef->length += length;
+ i--;
+ }
+ else
+ {
+ /* #3 */
+ VEC_safe_insert (range_s, value->unavailable, i, &newr);
+ }
+ }
+ else
+ {
+ /* #4 */
+ VEC_safe_insert (range_s, value->unavailable, i, &newr);
+ }
+
+ /* Check whether the ranges following the one we've just added or
+ touched can be folded in (#5 above). */
+ if (i + 1 < VEC_length (range_s, value->unavailable))
+ {
+ struct range *t;
+ struct range *r;
+ int removed = 0;
+ int next = i + 1;
+
+ /* Get the range we just touched. */
+ t = VEC_index (range_s, value->unavailable, i);
+ removed = 0;
+
+ i = next;
+ for (; VEC_iterate (range_s, value->unavailable, i, r); i++)
+ if (r->offset <= t->offset + t->length)
+ {
+ ULONGEST l, h;
+
+ l = min (t->offset, r->offset);
+ h = max (t->offset + t->length, r->offset + r->length);
+
+ t->offset = l;
+ t->length = h - l;
+
+ removed++;
+ }
+ else
+ {
+ /* If we couldn't merge this one, we won't be able to
+ merge following ones either, since the ranges are
+ always sorted by OFFSET. */
+ break;
+ }
+
+ if (removed != 0)
+ VEC_block_remove (range_s, value->unavailable, next, removed);
+ }
+}
+
+void
+mark_value_bytes_unavailable (struct value *value, int offset, int length)
+{
+ mark_value_bits_unavailable (value,
+ offset * TARGET_CHAR_BIT,
+ length * TARGET_CHAR_BIT);
+}
+
+/* Find the first range in RANGES that overlaps the range defined by
+ OFFSET and LENGTH, starting at element POS in the RANGES vector,
+ Returns the index into RANGES where such overlapping range was
+ found, or -1 if none was found. */
+
+static int
+find_first_range_overlap (VEC(range_s) *ranges, int pos,
+ int offset, int length)
+{
+ range_s *r;
+ int i;
+
+ for (i = pos; VEC_iterate (range_s, ranges, i, r); i++)
+ if (ranges_overlap (r->offset, r->length, offset, length))
+ return i;
+
+ return -1;
+}
+
+/* Compare LENGTH_BITS of memory at PTR1 + OFFSET1_BITS with the memory at
+ PTR2 + OFFSET2_BITS. Return 0 if the memory is the same, otherwise
+ return non-zero.
+
+ It must always be the case that:
+ OFFSET1_BITS % TARGET_CHAR_BIT == OFFSET2_BITS % TARGET_CHAR_BIT
+
+ It is assumed that memory can be accessed from:
+ PTR + (OFFSET_BITS / TARGET_CHAR_BIT)
+ to:
+ PTR + ((OFFSET_BITS + LENGTH_BITS + TARGET_CHAR_BIT - 1)
+ / TARGET_CHAR_BIT) */
+static int
+memcmp_with_bit_offsets (const gdb_byte *ptr1, size_t offset1_bits,
+ const gdb_byte *ptr2, size_t offset2_bits,
+ size_t length_bits)
+{
+ gdb_assert (offset1_bits % TARGET_CHAR_BIT
+ == offset2_bits % TARGET_CHAR_BIT);
+
+ if (offset1_bits % TARGET_CHAR_BIT != 0)
+ {
+ size_t bits;
+ gdb_byte mask, b1, b2;
+
+ /* The offset from the base pointers PTR1 and PTR2 is not a complete
+ number of bytes. A number of bits up to either the next exact
+ byte boundary, or LENGTH_BITS (which ever is sooner) will be
+ compared. */
+ bits = TARGET_CHAR_BIT - offset1_bits % TARGET_CHAR_BIT;
+ gdb_assert (bits < sizeof (mask) * TARGET_CHAR_BIT);
+ mask = (1 << bits) - 1;
+
+ if (length_bits < bits)
+ {
+ mask &= ~(gdb_byte) ((1 << (bits - length_bits)) - 1);
+ bits = length_bits;
+ }
+
+ /* Now load the two bytes and mask off the bits we care about. */
+ b1 = *(ptr1 + offset1_bits / TARGET_CHAR_BIT) & mask;
+ b2 = *(ptr2 + offset2_bits / TARGET_CHAR_BIT) & mask;
-/* Prototypes for local functions. */
+ if (b1 != b2)
+ return 1;
+
+ /* Now update the length and offsets to take account of the bits
+ we've just compared. */
+ length_bits -= bits;
+ offset1_bits += bits;
+ offset2_bits += bits;
+ }
+
+ if (length_bits % TARGET_CHAR_BIT != 0)
+ {
+ size_t bits;
+ size_t o1, o2;
+ gdb_byte mask, b1, b2;
+
+ /* The length is not an exact number of bytes. After the previous
+ IF.. block then the offsets are byte aligned, or the
+ length is zero (in which case this code is not reached). Compare
+ a number of bits at the end of the region, starting from an exact
+ byte boundary. */
+ bits = length_bits % TARGET_CHAR_BIT;
+ o1 = offset1_bits + length_bits - bits;
+ o2 = offset2_bits + length_bits - bits;
+
+ gdb_assert (bits < sizeof (mask) * TARGET_CHAR_BIT);
+ mask = ((1 << bits) - 1) << (TARGET_CHAR_BIT - bits);
+
+ gdb_assert (o1 % TARGET_CHAR_BIT == 0);
+ gdb_assert (o2 % TARGET_CHAR_BIT == 0);
+
+ b1 = *(ptr1 + o1 / TARGET_CHAR_BIT) & mask;
+ b2 = *(ptr2 + o2 / TARGET_CHAR_BIT) & mask;
+
+ if (b1 != b2)
+ return 1;
+
+ length_bits -= bits;
+ }
+
+ if (length_bits > 0)
+ {
+ /* We've now taken care of any stray "bits" at the start, or end of
+ the region to compare, the remainder can be covered with a simple
+ memcmp. */
+ gdb_assert (offset1_bits % TARGET_CHAR_BIT == 0);
+ gdb_assert (offset2_bits % TARGET_CHAR_BIT == 0);
+ gdb_assert (length_bits % TARGET_CHAR_BIT == 0);
+
+ return memcmp (ptr1 + offset1_bits / TARGET_CHAR_BIT,
+ ptr2 + offset2_bits / TARGET_CHAR_BIT,
+ length_bits / TARGET_CHAR_BIT);
+ }
+
+ /* Length is zero, regions match. */
+ return 0;
+}
+
+/* Helper function for value_available_contents_eq. The only difference is
+ that this function is bit rather than byte based.
+
+ Compare LENGTH bits of VAL1's contents starting at OFFSET1 bits with
+ LENGTH bits of VAL2's contents starting at OFFSET2 bits. Return true
+ if the available bits match. */
+
+static int
+value_available_contents_bits_eq (const struct value *val1, int offset1,
+ const struct value *val2, int offset2,
+ int length)
+{
+ int idx1 = 0, idx2 = 0;
+
+ /* See function description in value.h. */
+ gdb_assert (!val1->lazy && !val2->lazy);
+
+ while (length > 0)
+ {
+ range_s *r1, *r2;
+ ULONGEST l1, h1;
+ ULONGEST l2, h2;
+
+ idx1 = find_first_range_overlap (val1->unavailable, idx1,
+ offset1, length);
+ idx2 = find_first_range_overlap (val2->unavailable, idx2,
+ offset2, length);
+
+ /* The usual case is for both values to be completely available. */
+ if (idx1 == -1 && idx2 == -1)
+ return (memcmp_with_bit_offsets (val1->contents, offset1,
+ val2->contents, offset2,
+ length) == 0);
+ /* The contents only match equal if the available set matches as
+ well. */
+ else if (idx1 == -1 || idx2 == -1)
+ return 0;
+
+ gdb_assert (idx1 != -1 && idx2 != -1);
+
+ r1 = VEC_index (range_s, val1->unavailable, idx1);
+ r2 = VEC_index (range_s, val2->unavailable, idx2);
+
+ /* Get the unavailable windows intersected by the incoming
+ ranges. The first and last ranges that overlap the argument
+ range may be wider than said incoming arguments ranges. */
+ l1 = max (offset1, r1->offset);
+ h1 = min (offset1 + length, r1->offset + r1->length);
+
+ l2 = max (offset2, r2->offset);
+ h2 = min (offset2 + length, r2->offset + r2->length);
+
+ /* Make them relative to the respective start offsets, so we can
+ compare them for equality. */
+ l1 -= offset1;
+ h1 -= offset1;
+
+ l2 -= offset2;
+ h2 -= offset2;
+
+ /* Different availability, no match. */
+ if (l1 != l2 || h1 != h2)
+ return 0;
+
+ /* Compare the _available_ contents. */
+ if (memcmp_with_bit_offsets (val1->contents, offset1,
+ val2->contents, offset2, l1) != 0)
+ return 0;
+
+ length -= h1;
+ offset1 += h1;
+ offset2 += h1;
+ }
+
+ return 1;
+}
+
+int
+value_available_contents_eq (const struct value *val1, int offset1,
+ const struct value *val2, int offset2,
+ int length)
+{
+ return value_available_contents_bits_eq (val1, offset1 * TARGET_CHAR_BIT,
+ val2, offset2 * TARGET_CHAR_BIT,
+ length * TARGET_CHAR_BIT);
+}
+
+/* Prototypes for local functions. */
static void show_values (char *, int);
static struct value_history_chunk *value_history_chain;
-static int value_history_count; /* Abs number of last entry stored */
+static int value_history_count; /* Abs number of last entry stored. */
\f
/* List of all value objects currently allocated
/* Allocate the contents of VAL if it has not been allocated yet. */
-void
+static void
allocate_value_contents (struct value *val)
{
if (!val->contents)
struct value *
allocate_computed_value (struct type *type,
- struct lval_funcs *funcs,
+ const struct lval_funcs *funcs,
void *closure)
{
- struct value *v = allocate_value (type);
+ struct value *v = allocate_value_lazy (type);
VALUE_LVAL (v) = lval_computed;
v->location.computed.funcs = funcs;
v->location.computed.closure = closure;
- set_value_lazy (v, 1);
return v;
}
+/* Allocate NOT_LVAL value for type TYPE being OPTIMIZED_OUT. */
+
+struct value *
+allocate_optimized_out_value (struct type *type)
+{
+ struct value *retval = allocate_value_lazy (type);
+
+ set_value_optimized_out (retval, 1);
+ set_value_lazy (retval, 0);
+ return retval;
+}
+
/* Accessor methods. */
struct value *
return value->parent;
}
+/* See value.h. */
+
+void
+set_value_parent (struct value *value, struct value *parent)
+{
+ struct value *old = value->parent;
+
+ value->parent = parent;
+ if (parent != NULL)
+ value_incref (parent);
+ value_free (old);
+}
+
gdb_byte *
value_contents_raw (struct value *value)
{
return value->enclosing_type;
}
+/* Look at value.h for description. */
+
+struct type *
+value_actual_type (struct value *value, int resolve_simple_types,
+ int *real_type_found)
+{
+ struct value_print_options opts;
+ struct type *result;
+
+ get_user_print_options (&opts);
+
+ if (real_type_found)
+ *real_type_found = 0;
+ result = value_type (value);
+ if (opts.objectprint)
+ {
+ /* If result's target type is TYPE_CODE_STRUCT, proceed to
+ fetch its rtti type. */
+ if ((TYPE_CODE (result) == TYPE_CODE_PTR
+ || TYPE_CODE (result) == TYPE_CODE_REF)
+ && TYPE_CODE (check_typedef (TYPE_TARGET_TYPE (result)))
+ == TYPE_CODE_STRUCT)
+ {
+ struct type *real_type;
+
+ real_type = value_rtti_indirect_type (value, NULL, NULL, NULL);
+ if (real_type)
+ {
+ if (real_type_found)
+ *real_type_found = 1;
+ result = real_type;
+ }
+ }
+ else if (resolve_simple_types)
+ {
+ if (real_type_found)
+ *real_type_found = 1;
+ result = value_enclosing_type (value);
+ }
+ }
+
+ return result;
+}
+
+void
+error_value_optimized_out (void)
+{
+ error (_("value has been optimized out"));
+}
+
static void
-require_not_optimized_out (struct value *value)
+require_not_optimized_out (const struct value *value)
{
if (value->optimized_out)
- error (_("value has been optimized out"));
+ {
+ if (value->lval == lval_register)
+ error (_("register has not been saved in frame"));
+ else
+ error_value_optimized_out ();
+ }
+}
+
+static void
+require_available (const struct value *value)
+{
+ if (!VEC_empty (range_s, value->unavailable))
+ throw_error (NOT_AVAILABLE_ERROR, _("value is not available"));
}
const gdb_byte *
return value->contents;
}
+const gdb_byte *
+value_contents_for_printing_const (const struct value *value)
+{
+ gdb_assert (!value->lazy);
+ return value->contents;
+}
+
const gdb_byte *
value_contents_all (struct value *value)
{
const gdb_byte *result = value_contents_for_printing (value);
require_not_optimized_out (value);
+ require_available (value);
return result;
}
+/* Copy LENGTH bytes of SRC value's (all) contents
+ (value_contents_all) starting at SRC_OFFSET, into DST value's (all)
+ contents, starting at DST_OFFSET. If unavailable contents are
+ being copied from SRC, the corresponding DST contents are marked
+ unavailable accordingly. Neither DST nor SRC may be lazy
+ values.
+
+ It is assumed the contents of DST in the [DST_OFFSET,
+ DST_OFFSET+LENGTH) range are wholly available. */
+
+void
+value_contents_copy_raw (struct value *dst, int dst_offset,
+ struct value *src, int src_offset, int length)
+{
+ range_s *r;
+ int i;
+ int src_bit_offset, dst_bit_offset, bit_length;
+
+ /* A lazy DST would make that this copy operation useless, since as
+ soon as DST's contents were un-lazied (by a later value_contents
+ call, say), the contents would be overwritten. A lazy SRC would
+ mean we'd be copying garbage. */
+ gdb_assert (!dst->lazy && !src->lazy);
+
+ /* The overwritten DST range gets unavailability ORed in, not
+ replaced. Make sure to remember to implement replacing if it
+ turns out actually necessary. */
+ gdb_assert (value_bytes_available (dst, dst_offset, length));
+
+ /* Copy the data. */
+ memcpy (value_contents_all_raw (dst) + dst_offset,
+ value_contents_all_raw (src) + src_offset,
+ length);
+
+ /* Copy the meta-data, adjusted. */
+ src_bit_offset = src_offset * TARGET_CHAR_BIT;
+ dst_bit_offset = dst_offset * TARGET_CHAR_BIT;
+ bit_length = length * TARGET_CHAR_BIT;
+ for (i = 0; VEC_iterate (range_s, src->unavailable, i, r); i++)
+ {
+ ULONGEST h, l;
+
+ l = max (r->offset, src_bit_offset);
+ h = min (r->offset + r->length, src_bit_offset + bit_length);
+
+ if (l < h)
+ mark_value_bits_unavailable (dst,
+ dst_bit_offset + (l - src_bit_offset),
+ h - l);
+ }
+}
+
+/* Copy LENGTH bytes of SRC value's (all) contents
+ (value_contents_all) starting at SRC_OFFSET byte, into DST value's
+ (all) contents, starting at DST_OFFSET. If unavailable contents
+ are being copied from SRC, the corresponding DST contents are
+ marked unavailable accordingly. DST must not be lazy. If SRC is
+ lazy, it will be fetched now. If SRC is not valid (is optimized
+ out), an error is thrown.
+
+ It is assumed the contents of DST in the [DST_OFFSET,
+ DST_OFFSET+LENGTH) range are wholly available. */
+
+void
+value_contents_copy (struct value *dst, int dst_offset,
+ struct value *src, int src_offset, int length)
+{
+ require_not_optimized_out (src);
+
+ if (src->lazy)
+ value_fetch_lazy (src);
+
+ value_contents_copy_raw (dst, dst_offset, src, src_offset, length);
+}
+
int
value_lazy (struct value *value)
{
{
const gdb_byte *result = value_contents_writeable (value);
require_not_optimized_out (value);
+ require_available (value);
return result;
}
{
struct type *type1;
struct type *type2;
- int len;
type1 = check_typedef (value_type (val1));
type2 = check_typedef (value_type (val2));
- len = TYPE_LENGTH (type1);
- if (len != TYPE_LENGTH (type2))
+ if (TYPE_LENGTH (type1) != TYPE_LENGTH (type2))
return 0;
- return (memcmp (value_contents (val1), value_contents (val2), len) == 0);
+ return (memcmp (value_contents (val1), value_contents (val2),
+ TYPE_LENGTH (type1)) == 0);
}
int
value_optimized_out (struct value *value)
+{
+ /* We can only know if a value is optimized out once we have tried to
+ fetch it. */
+ if (!value->optimized_out && value->lazy)
+ value_fetch_lazy (value);
+
+ return value->optimized_out;
+}
+
+int
+value_optimized_out_const (const struct value *value)
{
return value->optimized_out;
}
if (!value->optimized_out)
return 0;
if (value->lval != lval_computed
- || !value->location.computed.funcs->check_validity)
+ || !value->location.computed.funcs->check_any_valid)
return 1;
- return value->location.computed.funcs->check_all_valid (value);
+ return !value->location.computed.funcs->check_any_valid (value);
}
int
value_bits_valid (const struct value *value, int offset, int length)
{
- if (value == NULL || !value->optimized_out)
+ if (!value->optimized_out)
return 1;
if (value->lval != lval_computed
|| !value->location.computed.funcs->check_validity)
length);
}
+int
+value_bits_synthetic_pointer (const struct value *value,
+ int offset, int length)
+{
+ if (value->lval != lval_computed
+ || !value->location.computed.funcs->check_synthetic_pointer)
+ return 0;
+ return value->location.computed.funcs->check_synthetic_pointer (value,
+ offset,
+ length);
+}
+
int
value_embedded_offset (struct value *value)
{
value->pointed_to_offset = val;
}
-struct lval_funcs *
-value_computed_funcs (struct value *v)
+const struct lval_funcs *
+value_computed_funcs (const struct value *v)
{
- gdb_assert (VALUE_LVAL (v) == lval_computed);
+ gdb_assert (value_lval_const (v) == lval_computed);
return v->location.computed.funcs;
}
return &value->lval;
}
+enum lval_type
+value_lval_const (const struct value *value)
+{
+ return value->lval;
+}
+
CORE_ADDR
-value_address (struct value *value)
+value_address (const struct value *value)
{
if (value->lval == lval_internalvar
|| value->lval == lval_internalvar_component)
return 0;
- return value->location.address + value->offset;
+ if (value->parent != NULL)
+ return value_address (value->parent) + value->offset;
+ else
+ return value->location.address + value->offset;
}
CORE_ADDR
{
return value->modifiable;
}
-void
-deprecated_set_value_modifiable (struct value *value, int modifiable)
-{
- value->modifiable = modifiable;
-}
\f
/* Return a mark in the value chain. All values allocated after the
mark is obtained (except for those released) are subject to being freed
if (VALUE_LVAL (val) == lval_computed)
{
- struct lval_funcs *funcs = val->location.computed.funcs;
+ const struct lval_funcs *funcs = val->location.computed.funcs;
if (funcs->free_closure)
funcs->free_closure (val);
}
xfree (val->contents);
+ VEC_free (range_s, val->unavailable);
}
xfree (val);
}
for (val = all_values; val && val != mark; val = next)
{
next = val->next;
+ val->released = 1;
value_free (val);
}
all_values = val;
for (val = all_values; val; val = next)
{
next = val->next;
+ val->released = 1;
value_free (val);
}
all_values = 0;
}
+/* Frees all the elements in a chain of values. */
+
+void
+free_value_chain (struct value *v)
+{
+ struct value *next;
+
+ for (; v; v = next)
+ {
+ next = value_next (v);
+ value_free (v);
+ }
+}
+
/* Remove VAL from the chain all_values
so it will not be freed automatically. */
if (all_values == val)
{
all_values = val->next;
+ val->next = NULL;
+ val->released = 1;
return;
}
if (v->next == val)
{
v->next = val->next;
+ val->next = NULL;
+ val->released = 1;
break;
}
}
}
+/* If the value is not already released, release it.
+ If the value is already released, increment its reference count.
+ That is, this function ensures that the value is released from the
+ value chain and that the caller owns a reference to it. */
+
+void
+release_value_or_incref (struct value *val)
+{
+ if (val->released)
+ value_incref (val);
+ else
+ release_value (val);
+}
+
/* Release all values up to mark */
struct value *
value_release_to_mark (struct value *mark)
struct value *next;
for (val = next = all_values; next; next = next->next)
- if (next->next == mark)
- {
- all_values = next->next;
- next->next = NULL;
- return val;
- }
+ {
+ if (next->next == mark)
+ {
+ all_values = next->next;
+ next->next = NULL;
+ return val;
+ }
+ next->released = 1;
+ }
all_values = 0;
return val;
}
TYPE_LENGTH (value_enclosing_type (arg)));
}
- val->parent = arg->parent;
- if (val->parent)
- value_incref (val->parent);
+ val->unavailable = VEC_copy (range_s, arg->unavailable);
+ set_value_parent (val, arg->parent);
if (VALUE_LVAL (val) == lval_computed)
{
- struct lval_funcs *funcs = val->location.computed.funcs;
+ const struct lval_funcs *funcs = val->location.computed.funcs;
if (funcs->copy_closure)
val->location.computed.closure = funcs->copy_closure (val);
return val;
}
+/* Return a version of ARG that is non-lvalue. */
+
+struct value *
+value_non_lval (struct value *arg)
+{
+ if (VALUE_LVAL (arg) != not_lval)
+ {
+ struct type *enc_type = value_enclosing_type (arg);
+ struct value *val = allocate_value (enc_type);
+
+ memcpy (value_contents_all_raw (val), value_contents_all (arg),
+ TYPE_LENGTH (enc_type));
+ val->type = arg->type;
+ set_value_embedded_offset (val, value_embedded_offset (arg));
+ set_value_pointed_to_offset (val, value_pointed_to_offset (arg));
+ return val;
+ }
+ return arg;
+}
+
void
set_value_component_location (struct value *component,
const struct value *whole)
component->location = whole->location;
if (whole->lval == lval_computed)
{
- struct lval_funcs *funcs = whole->location.computed.funcs;
+ const struct lval_funcs *funcs = whole->location.computed.funcs;
if (funcs->copy_closure)
component->location.computed.closure = funcs->copy_closure (whole);
/* Access to the value history. */
/* Record a new value in the value history.
- Returns the absolute history index of the entry.
- Result of -1 indicates the value was not saved; otherwise it is the
- value history index of this new item. */
+ Returns the absolute history index of the entry. */
int
record_latest_value (struct value *val)
from. This is a bit dubious, because then *&$1 does not just return $1
but the current contents of that location. c'est la vie... */
val->modifiable = 0;
- release_value (val);
+
+ /* The value may have already been released, in which case we're adding a
+ new reference for its entry in the history. That is why we call
+ release_value_or_incref here instead of release_value. */
+ release_value_or_incref (val);
/* Here we treat value_history_count as origin-zero
and applying to the value being stored now. */
/* Now absnum is always absolute and origin zero. */
chunk = value_history_chain;
- for (i = (value_history_count - 1) / VALUE_HISTORY_CHUNK - absnum / VALUE_HISTORY_CHUNK;
+ for (i = (value_history_count - 1) / VALUE_HISTORY_CHUNK
+ - absnum / VALUE_HISTORY_CHUNK;
i > 0; i--)
chunk = chunk->next;
/* The variable holds an integer value. */
INTERNALVAR_INTEGER,
- /* The variable holds a pointer value. */
- INTERNALVAR_POINTER,
-
/* The variable holds a GDB-provided string. */
INTERNALVAR_STRING,
struct value *value;
/* The call-back routine used with INTERNALVAR_MAKE_VALUE. */
- internalvar_make_value make_value;
+ struct
+ {
+ /* The functions to call. */
+ const struct internalvar_funcs *functions;
+
+ /* The function's user-data. */
+ void *data;
+ } make_value;
/* The internal function used with INTERNALVAR_FUNCTION. */
struct
LONGEST val;
} integer;
- /* A pointer value used with INTERNALVAR_POINTER. */
- struct
- {
- struct type *type;
- CORE_ADDR val;
- } pointer;
-
/* A string value used with INTERNALVAR_STRING. */
char *string;
} u;
static struct internalvar *internalvars;
-/* If the variable does not already exist create it and give it the value given.
- If no value is given then the default is zero. */
+/* If the variable does not already exist create it and give it the
+ value given. If no value is given then the default is zero. */
static void
init_if_undefined_command (char* args, int from_tty)
{
/* Extract the variable from the parsed expression.
In the case of an assign the lvalue will be in elts[1] and elts[2]. */
if (expr->elts[1].opcode != OP_INTERNALVAR)
- error (_("The first parameter to init-if-undefined should be a GDB variable."));
+ error (_("The first parameter to init-if-undefined "
+ "should be a GDB variable."));
intvar = expr->elts[2].internalvar;
/* Only evaluate the expression if the lvalue is void.
return NULL;
}
+/* Complete NAME by comparing it to the names of internal variables.
+ Returns a vector of newly allocated strings, or NULL if no matches
+ were found. */
+
+VEC (char_ptr) *
+complete_internalvar (const char *name)
+{
+ VEC (char_ptr) *result = NULL;
+ struct internalvar *var;
+ int len;
+
+ len = strlen (name);
+
+ for (var = internalvars; var; var = var->next)
+ if (strncmp (var->name, name, len) == 0)
+ {
+ char *r = xstrdup (var->name);
+
+ VEC_safe_push (char_ptr, result, r);
+ }
+
+ return result;
+}
/* Create an internal variable with name NAME and with a void value.
NAME should not normally include a dollar sign. */
/* Create an internal variable with name NAME and register FUN as the
function that value_of_internalvar uses to create a value whenever
this variable is referenced. NAME should not normally include a
- dollar sign. */
+ dollar sign. DATA is passed uninterpreted to FUN when it is
+ called. CLEANUP, if not NULL, is called when the internal variable
+ is destroyed. It is passed DATA as its only argument. */
struct internalvar *
-create_internalvar_type_lazy (char *name, internalvar_make_value fun)
+create_internalvar_type_lazy (const char *name,
+ const struct internalvar_funcs *funcs,
+ void *data)
{
struct internalvar *var = create_internalvar (name);
var->kind = INTERNALVAR_MAKE_VALUE;
- var->u.make_value = fun;
+ var->u.make_value.functions = funcs;
+ var->u.make_value.data = data;
return var;
}
+/* See documentation in value.h. */
+
+int
+compile_internalvar_to_ax (struct internalvar *var,
+ struct agent_expr *expr,
+ struct axs_value *value)
+{
+ if (var->kind != INTERNALVAR_MAKE_VALUE
+ || var->u.make_value.functions->compile_to_ax == NULL)
+ return 0;
+
+ var->u.make_value.functions->compile_to_ax (var, expr, value,
+ var->u.make_value.data);
+ return 1;
+}
+
/* Look up an internal variable with name NAME. NAME should not
normally include a dollar sign.
value_of_internalvar (struct gdbarch *gdbarch, struct internalvar *var)
{
struct value *val;
+ struct trace_state_variable *tsv;
+
+ /* If there is a trace state variable of the same name, assume that
+ is what we really want to see. */
+ tsv = find_trace_state_variable (var->name);
+ if (tsv)
+ {
+ tsv->value_known = target_get_trace_state_variable_value (tsv->number,
+ &(tsv->value));
+ if (tsv->value_known)
+ val = value_from_longest (builtin_type (gdbarch)->builtin_int64,
+ tsv->value);
+ else
+ val = allocate_value (builtin_type (gdbarch)->builtin_void);
+ return val;
+ }
switch (var->kind)
{
val = value_from_longest (var->u.integer.type, var->u.integer.val);
break;
- case INTERNALVAR_POINTER:
- val = value_from_pointer (var->u.pointer.type, var->u.pointer.val);
- break;
-
case INTERNALVAR_STRING:
val = value_cstring (var->u.string, strlen (var->u.string),
builtin_type (gdbarch)->builtin_char);
break;
case INTERNALVAR_MAKE_VALUE:
- val = (*var->u.make_value) (gdbarch, var);
+ val = (*var->u.make_value.functions->make_value) (gdbarch, var,
+ var->u.make_value.data);
break;
default:
- internal_error (__FILE__, __LINE__, "bad kind");
+ internal_error (__FILE__, __LINE__, _("bad kind"));
}
/* Change the VALUE_LVAL to lval_internalvar so that future operations
int
get_internalvar_integer (struct internalvar *var, LONGEST *result)
{
- switch (var->kind)
+ if (var->kind == INTERNALVAR_INTEGER)
{
- case INTERNALVAR_INTEGER:
*result = var->u.integer.val;
return 1;
+ }
- default:
- return 0;
+ if (var->kind == INTERNALVAR_VALUE)
+ {
+ struct type *type = check_typedef (value_type (var->u.value));
+
+ if (TYPE_CODE (type) == TYPE_CODE_INT)
+ {
+ *result = value_as_long (var->u.value);
+ return 1;
+ }
}
+
+ return 0;
}
static int
default:
/* We can never get a component of any other kind. */
- internal_error (__FILE__, __LINE__, "set_internalvar_component");
+ internal_error (__FILE__, __LINE__, _("set_internalvar_component"));
}
}
case TYPE_CODE_INTERNAL_FUNCTION:
gdb_assert (VALUE_LVAL (val) == lval_internalvar);
- new_kind = INTERNALVAR_FUNCTION;
- get_internalvar_function (VALUE_INTERNALVAR (val),
- &new_data.fn.function);
- /* Copies created here are never canonical. */
- break;
-
- case TYPE_CODE_INT:
- new_kind = INTERNALVAR_INTEGER;
- new_data.integer.type = value_type (val);
- new_data.integer.val = value_as_long (val);
- break;
-
- case TYPE_CODE_PTR:
- new_kind = INTERNALVAR_POINTER;
- new_data.pointer.type = value_type (val);
- new_data.pointer.val = value_as_address (val);
+ new_kind = INTERNALVAR_FUNCTION;
+ get_internalvar_function (VALUE_INTERNALVAR (val),
+ &new_data.fn.function);
+ /* Copies created here are never canonical. */
break;
default:
xfree (var->u.string);
break;
+ case INTERNALVAR_MAKE_VALUE:
+ if (var->u.make_value.functions->destroy != NULL)
+ var->u.make_value.functions->destroy (var->u.make_value.data);
+ break;
+
default:
break;
}
static void
function_destroyer (struct cmd_list_element *self, void *ignore)
{
- xfree (self->name);
+ xfree ((char *) self->name);
xfree (self->doc);
}
= copy_type_recursive (objfile, var->u.integer.type, copied_types);
break;
- case INTERNALVAR_POINTER:
- if (TYPE_OBJFILE (var->u.pointer.type) == objfile)
- var->u.pointer.type
- = copy_type_recursive (objfile, var->u.pointer.type, copied_types);
- break;
-
case INTERNALVAR_VALUE:
preserve_one_value (var->u.value, objfile, copied_types);
break;
for (var = internalvars; var; var = var->next)
preserve_one_internalvar (var, objfile, copied_types);
- preserve_python_values (objfile, copied_types);
+ preserve_ext_lang_values (objfile, copied_types);
htab_delete (copied_types);
}
get_user_print_options (&opts);
for (var = internalvars; var; var = var->next)
{
+ volatile struct gdb_exception ex;
+
if (!varseen)
{
varseen = 1;
}
printf_filtered (("$%s = "), var->name);
- value_print (value_of_internalvar (gdbarch, var), gdb_stdout,
- &opts);
+
+ TRY_CATCH (ex, RETURN_MASK_ERROR)
+ {
+ struct value *val;
+
+ val = value_of_internalvar (gdbarch, var);
+ value_print (val, gdb_stdout, &opts);
+ }
+ if (ex.reason < 0)
+ fprintf_filtered (gdb_stdout, _("<error: %s>"), ex.message);
printf_filtered (("\n"));
}
if (!varseen)
- printf_unfiltered (_("\
-No debugger convenience variables now defined.\n\
-Convenience variables have names starting with \"$\";\n\
-use \"set\" as in \"set $foo = 5\" to define them.\n"));
+ {
+ /* This text does not mention convenience functions on purpose.
+ The user can't create them except via Python, and if Python support
+ is installed this message will never be printed ($_streq will
+ exist). */
+ printf_unfiltered (_("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"));
+ }
}
\f
/* Extract a value as a C number (either long or double).
return foo;
}
-/* Extract a value as a C pointer. Does not deallocate the value.
+/* Extract a value as a C pointer. Does not deallocate the value.
Note that val's type may not actually be a pointer; value_as_long
handles all the cases. */
CORE_ADDR
int len;
int nosign;
- *invp = 0; /* Assume valid. */
+ *invp = 0; /* Assume valid. */
CHECK_TYPEDEF (type);
code = TYPE_CODE (type);
len = TYPE_LENGTH (type);
}
\f
-/* Get the value of the FIELDN'th field (which must be static) of
- TYPE. Return NULL if the field doesn't exist or has been
- optimized out. */
+/* Get the value of the FIELDNO'th field (which must be static) of
+ TYPE. */
struct value *
value_static_field (struct type *type, int fieldno)
{
struct value *retval;
- if (TYPE_FIELD_LOC_KIND (type, fieldno) == FIELD_LOC_KIND_PHYSADDR)
+ switch (TYPE_FIELD_LOC_KIND (type, fieldno))
{
+ case FIELD_LOC_KIND_PHYSADDR:
retval = value_at_lazy (TYPE_FIELD_TYPE (type, fieldno),
TYPE_FIELD_STATIC_PHYSADDR (type, fieldno));
- }
- else
+ break;
+ case FIELD_LOC_KIND_PHYSNAME:
{
- char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (type, fieldno);
- /*TYPE_FIELD_NAME (type, fieldno);*/
+ const char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (type, fieldno);
+ /* TYPE_FIELD_NAME (type, fieldno); */
struct symbol *sym = lookup_symbol (phys_name, 0, VAR_DOMAIN, 0);
if (sym == NULL)
{
/* With some compilers, e.g. HP aCC, static data members are
- reported as non-debuggable symbols */
- struct minimal_symbol *msym = lookup_minimal_symbol (phys_name,
- NULL, NULL);
+ reported as non-debuggable symbols. */
+ struct bound_minimal_symbol msym
+ = lookup_minimal_symbol (phys_name, NULL, NULL);
- if (!msym)
- return NULL;
+ if (!msym.minsym)
+ return allocate_optimized_out_value (type);
else
{
retval = value_at_lazy (TYPE_FIELD_TYPE (type, fieldno),
- SYMBOL_VALUE_ADDRESS (msym));
+ BMSYMBOL_VALUE_ADDRESS (msym));
}
}
else
- {
- /* SYM should never have a SYMBOL_CLASS which will require
- read_var_value to use the FRAME parameter. */
- if (symbol_read_needs_frame (sym))
- warning (_("static field's value depends on the current "
- "frame - bad debug info?"));
- retval = read_var_value (sym, NULL);
- }
- if (retval && VALUE_LVAL (retval) == lval_memory)
- SET_FIELD_PHYSADDR (TYPE_FIELD (type, fieldno),
- value_address (retval));
+ retval = value_of_variable (sym, NULL);
+ break;
+ }
+ default:
+ gdb_assert_not_reached ("unexpected field location kind");
}
+
return retval;
}
-/* Change the enclosing type of a value object VAL to NEW_ENCL_TYPE.
- You have to be careful here, since the size of the data area for the value
- is set by the length of the enclosing type. So if NEW_ENCL_TYPE is bigger
- than the old enclosing type, you have to allocate more space for the data.
- The return value is a pointer to the new version of this value structure. */
+/* Change the enclosing type of a value object VAL to NEW_ENCL_TYPE.
+ You have to be careful here, since the size of the data area for the value
+ is set by the length of the enclosing type. So if NEW_ENCL_TYPE is bigger
+ than the old enclosing type, you have to allocate more space for the
+ data. */
-struct value *
-value_change_enclosing_type (struct value *val, struct type *new_encl_type)
+void
+set_value_enclosing_type (struct value *val, struct type *new_encl_type)
{
if (TYPE_LENGTH (new_encl_type) > TYPE_LENGTH (value_enclosing_type (val)))
val->contents =
(gdb_byte *) xrealloc (val->contents, TYPE_LENGTH (new_encl_type));
val->enclosing_type = new_encl_type;
- return val;
}
/* 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 (non-static) fields.
- FIELDNO says which field. */
+ FIELDNO says which field. */
struct value *
value_primitive_field (struct value *arg1, int offset,
description correctly. */
check_typedef (type);
- /* Handle packed fields */
-
if (TYPE_FIELD_BITSIZE (arg_type, fieldno))
{
- /* Create a new value for the bitfield, with bitpos and bitsize
+ /* Handle packed fields.
+
+ Create a new value for the bitfield, with bitpos and bitsize
set. If possible, arrange offset and bitpos so that we can
do a single aligned read of the size of the containing type.
Otherwise, adjust offset to the byte containing the first
bit. Assume that the address, offset, and embedded offset
are sufficiently aligned. */
+
int bitpos = TYPE_FIELD_BITPOS (arg_type, fieldno);
int container_bitsize = TYPE_LENGTH (type) * 8;
- v = allocate_value_lazy (type);
- v->bitsize = TYPE_FIELD_BITSIZE (arg_type, fieldno);
- if ((bitpos % container_bitsize) + v->bitsize <= container_bitsize
- && TYPE_LENGTH (type) <= (int) sizeof (LONGEST))
- v->bitpos = bitpos % container_bitsize;
+ if (arg1->optimized_out)
+ v = allocate_optimized_out_value (type);
else
- v->bitpos = bitpos % 8;
- v->offset = value_embedded_offset (arg1)
- + (bitpos - v->bitpos) / 8;
- v->parent = arg1;
- value_incref (v->parent);
- if (!value_lazy (arg1))
- value_fetch_lazy (v);
+ {
+ v = allocate_value_lazy (type);
+ v->bitsize = TYPE_FIELD_BITSIZE (arg_type, fieldno);
+ if ((bitpos % container_bitsize) + v->bitsize <= container_bitsize
+ && TYPE_LENGTH (type) <= (int) sizeof (LONGEST))
+ v->bitpos = bitpos % container_bitsize;
+ else
+ v->bitpos = bitpos % 8;
+ v->offset = (value_embedded_offset (arg1)
+ + offset
+ + (bitpos - v->bitpos) / 8);
+ set_value_parent (v, arg1);
+ if (!value_lazy (arg1))
+ value_fetch_lazy (v);
+ }
}
else if (fieldno < TYPE_N_BASECLASSES (arg_type))
{
/* This field is actually a base subobject, so preserve the
- entire object's contents for later references to virtual
- bases, etc. */
+ entire object's contents for later references to virtual
+ bases, etc. */
+ int boffset;
/* Lazy register values with offsets are not supported. */
if (VALUE_LVAL (arg1) == lval_register && value_lazy (arg1))
value_fetch_lazy (arg1);
- if (value_lazy (arg1))
- v = allocate_value_lazy (value_enclosing_type (arg1));
+ /* The optimized_out flag is only set correctly once a lazy value is
+ loaded, having just loaded some lazy values we should check the
+ optimized out case now. */
+ if (arg1->optimized_out)
+ v = allocate_optimized_out_value (type);
else
{
- v = allocate_value (value_enclosing_type (arg1));
- memcpy (value_contents_all_raw (v), value_contents_all_raw (arg1),
- TYPE_LENGTH (value_enclosing_type (arg1)));
+ /* We special case virtual inheritance here because this
+ requires access to the contents, which we would rather avoid
+ for references to ordinary fields of unavailable values. */
+ if (BASETYPE_VIA_VIRTUAL (arg_type, fieldno))
+ boffset = baseclass_offset (arg_type, fieldno,
+ value_contents (arg1),
+ value_embedded_offset (arg1),
+ value_address (arg1),
+ arg1);
+ else
+ boffset = TYPE_FIELD_BITPOS (arg_type, fieldno) / 8;
+
+ if (value_lazy (arg1))
+ v = allocate_value_lazy (value_enclosing_type (arg1));
+ else
+ {
+ v = allocate_value (value_enclosing_type (arg1));
+ value_contents_copy_raw (v, 0, arg1, 0,
+ TYPE_LENGTH (value_enclosing_type (arg1)));
+ }
+ v->type = type;
+ v->offset = value_offset (arg1);
+ v->embedded_offset = offset + value_embedded_offset (arg1) + boffset;
}
- v->type = type;
- v->offset = value_offset (arg1);
- v->embedded_offset = (offset + value_embedded_offset (arg1)
- + TYPE_FIELD_BITPOS (arg_type, fieldno) / 8);
}
else
{
if (VALUE_LVAL (arg1) == lval_register && value_lazy (arg1))
value_fetch_lazy (arg1);
- if (value_lazy (arg1))
+ /* The optimized_out flag is only set correctly once a lazy value is
+ loaded, having just loaded some lazy values we should check for
+ the optimized out case now. */
+ if (arg1->optimized_out)
+ v = allocate_optimized_out_value (type);
+ else if (value_lazy (arg1))
v = allocate_value_lazy (type);
else
{
v = allocate_value (type);
- memcpy (value_contents_raw (v),
- value_contents_raw (arg1) + offset,
- TYPE_LENGTH (type));
+ value_contents_copy_raw (v, value_embedded_offset (v),
+ arg1, value_embedded_offset (arg1) + offset,
+ TYPE_LENGTH (type));
}
v->offset = (value_offset (arg1) + offset
+ value_embedded_offset (arg1));
/* Given a value ARG1 of a struct or union type,
extract and return the value of one of its (non-static) fields.
- FIELDNO says which field. */
+ FIELDNO says which field. */
struct value *
value_field (struct value *arg1, int fieldno)
J is an index into F which provides the desired method.
We only use the symbol for its address, so be happy with either a
- full symbol or a minimal symbol.
- */
+ full symbol or a minimal symbol. */
struct value *
-value_fn_field (struct value **arg1p, struct fn_field *f, int j, struct type *type,
+value_fn_field (struct value **arg1p, struct fn_field *f,
+ int j, struct type *type,
int offset)
{
struct value *v;
struct type *ftype = TYPE_FN_FIELD_TYPE (f, j);
- char *physname = TYPE_FN_FIELD_PHYSNAME (f, j);
+ const char *physname = TYPE_FN_FIELD_PHYSNAME (f, j);
struct symbol *sym;
- struct minimal_symbol *msym;
+ struct bound_minimal_symbol msym;
sym = lookup_symbol (physname, 0, VAR_DOMAIN, 0);
if (sym != NULL)
{
- msym = NULL;
+ memset (&msym, 0, sizeof (msym));
}
else
{
gdb_assert (sym == NULL);
- msym = lookup_minimal_symbol (physname, NULL, NULL);
- if (msym == NULL)
+ msym = lookup_bound_minimal_symbol (physname);
+ if (msym.minsym == NULL)
return NULL;
}
{
/* The minimal symbol might point to a function descriptor;
resolve it to the actual code address instead. */
- struct objfile *objfile = msymbol_objfile (msym);
+ struct objfile *objfile = msym.objfile;
struct gdbarch *gdbarch = get_objfile_arch (objfile);
set_value_address (v,
gdbarch_convert_from_func_ptr_addr
- (gdbarch, SYMBOL_VALUE_ADDRESS (msym), ¤t_target));
+ (gdbarch, BMSYMBOL_VALUE_ADDRESS (msym), ¤t_target));
}
if (arg1p)
value_addr (*arg1p)));
/* Move the `this' pointer according to the offset.
- VALUE_OFFSET (*arg1p) += offset;
- */
+ VALUE_OFFSET (*arg1p) += offset; */
}
return v;
}
\f
-/* Unpack a bitfield of the specified FIELD_TYPE, from the anonymous
- object at VALADDR. The bitfield starts at BITPOS bits and contains
- BITSIZE bits.
-
- 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. */
+/* Helper function for both unpack_value_bits_as_long and
+ unpack_bits_as_long. See those functions for more details on the
+ interface; the only difference is that this function accepts either
+ a NULL or a non-NULL ORIGINAL_VALUE. */
-LONGEST
-unpack_bits_as_long (struct type *field_type, const gdb_byte *valaddr,
- int bitpos, int bitsize)
+static int
+unpack_value_bits_as_long_1 (struct type *field_type, const gdb_byte *valaddr,
+ int embedded_offset, int bitpos, int bitsize,
+ const struct value *original_value,
+ LONGEST *result)
{
enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (field_type));
ULONGEST val;
ULONGEST valmask;
int lsbcount;
int bytes_read;
+ int read_offset;
/* Read the minimum number of bytes required; there may not be
enough bytes to read an entire ULONGEST. */
else
bytes_read = TYPE_LENGTH (field_type);
- val = extract_unsigned_integer (valaddr + bitpos / 8,
+ read_offset = bitpos / 8;
+
+ if (original_value != NULL
+ && !value_bits_available (original_value, embedded_offset + bitpos,
+ bitsize))
+ return 0;
+
+ val = extract_unsigned_integer (valaddr + embedded_offset + read_offset,
bytes_read, byte_order);
- /* Extract bits. See comment above. */
+ /* Extract bits. See comment above. */
if (gdbarch_bits_big_endian (get_type_arch (field_type)))
lsbcount = (bytes_read * 8 - bitpos % 8 - bitsize);
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 the field is signed, and is negative, then sign extend. */
if ((bitsize > 0) && (bitsize < 8 * (int) sizeof (val)))
{
}
}
}
- return (val);
+
+ *result = val;
+ return 1;
}
-/* Unpack a field FIELDNO of the specified TYPE, from the anonymous object at
- VALADDR. See unpack_bits_as_long for more details. */
+/* Unpack a bitfield of the specified FIELD_TYPE, from the object at
+ VALADDR + EMBEDDED_OFFSET, and store the result in *RESULT.
+ VALADDR points to the contents of ORIGINAL_VALUE, which must not be
+ NULL. The bitfield starts at BITPOS bits and contains BITSIZE
+ bits.
-LONGEST
-unpack_field_as_long (struct type *type, const gdb_byte *valaddr, int fieldno)
+ Returns false if the value contents are unavailable, otherwise
+ returns true, indicating a valid value has been stored in *RESULT.
+
+ 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. */
+
+int
+unpack_value_bits_as_long (struct type *field_type, const gdb_byte *valaddr,
+ int embedded_offset, int bitpos, int bitsize,
+ const struct value *original_value,
+ LONGEST *result)
+{
+ gdb_assert (original_value != NULL);
+
+ return unpack_value_bits_as_long_1 (field_type, valaddr, embedded_offset,
+ bitpos, bitsize, original_value, result);
+
+}
+
+/* Unpack a field FIELDNO of the specified TYPE, from the object at
+ VALADDR + EMBEDDED_OFFSET. VALADDR points to the contents of
+ ORIGINAL_VALUE. See unpack_value_bits_as_long for more
+ details. */
+
+static int
+unpack_value_field_as_long_1 (struct type *type, const gdb_byte *valaddr,
+ int embedded_offset, int fieldno,
+ const struct value *val, LONGEST *result)
{
int bitpos = TYPE_FIELD_BITPOS (type, fieldno);
int bitsize = TYPE_FIELD_BITSIZE (type, fieldno);
struct type *field_type = TYPE_FIELD_TYPE (type, fieldno);
- return unpack_bits_as_long (field_type, valaddr, bitpos, bitsize);
+ return unpack_value_bits_as_long_1 (field_type, valaddr, embedded_offset,
+ bitpos, bitsize, val,
+ result);
+}
+
+/* Unpack a field FIELDNO of the specified TYPE, from the object at
+ VALADDR + EMBEDDED_OFFSET. VALADDR points to the contents of
+ ORIGINAL_VALUE, which must not be NULL. See
+ unpack_value_bits_as_long for more details. */
+
+int
+unpack_value_field_as_long (struct type *type, const gdb_byte *valaddr,
+ int embedded_offset, int fieldno,
+ const struct value *val, LONGEST *result)
+{
+ gdb_assert (val != NULL);
+
+ return unpack_value_field_as_long_1 (type, valaddr, embedded_offset,
+ fieldno, val, result);
+}
+
+/* Unpack a field FIELDNO of the specified TYPE, from the anonymous
+ object at VALADDR. See unpack_value_bits_as_long for more details.
+ This function differs from unpack_value_field_as_long in that it
+ operates without a struct value object. */
+
+LONGEST
+unpack_field_as_long (struct type *type, const gdb_byte *valaddr, int fieldno)
+{
+ LONGEST result;
+
+ unpack_value_field_as_long_1 (type, valaddr, 0, fieldno, NULL, &result);
+ return result;
+}
+
+/* Return a new value with type TYPE, which is FIELDNO field of the
+ object at VALADDR + EMBEDDEDOFFSET. VALADDR points to the contents
+ of VAL. If the VAL's contents required to extract the bitfield
+ from are unavailable, the new value is correspondingly marked as
+ unavailable. */
+
+struct value *
+value_field_bitfield (struct type *type, int fieldno,
+ const gdb_byte *valaddr,
+ int embedded_offset, const struct value *val)
+{
+ LONGEST l;
+
+ if (!unpack_value_field_as_long (type, valaddr, embedded_offset, fieldno,
+ val, &l))
+ {
+ struct type *field_type = TYPE_FIELD_TYPE (type, fieldno);
+ struct value *retval = allocate_value (field_type);
+ mark_value_bytes_unavailable (retval, 0, TYPE_LENGTH (field_type));
+ return retval;
+ }
+ else
+ {
+ return value_from_longest (TYPE_FIELD_TYPE (type, fieldno), l);
+ }
}
/* 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.
- Requires 0 < BITSIZE <= lbits, 0 <= BITPOS+BITSIZE <= lbits, and
+ indicate which bits (in target bit order) comprise the bitfield.
+ Requires 0 < BITSIZE <= lbits, 0 <= BITPOS % 8 + BITSIZE <= lbits, and
0 <= BITPOS, where lbits is the size of a LONGEST in bits. */
void
enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
ULONGEST oword;
ULONGEST mask = (ULONGEST) -1 >> (8 * sizeof (ULONGEST) - bitsize);
+ int bytesize;
+
+ /* Normalize BITPOS. */
+ addr += bitpos / 8;
+ bitpos %= 8;
/* If a negative fieldval fits in the field in question, chop
off the sign extension bits. */
fieldval &= mask;
}
- oword = extract_unsigned_integer (addr, sizeof oword, byte_order);
+ /* Ensure no bytes outside of the modified ones get accessed as it may cause
+ false valgrind reports. */
+
+ bytesize = (bitpos + bitsize + 7) / 8;
+ oword = extract_unsigned_integer (addr, bytesize, byte_order);
/* Shifting for bit field depends on endianness of the target machine. */
if (gdbarch_bits_big_endian (get_type_arch (type)))
- bitpos = sizeof (oword) * 8 - bitpos - bitsize;
+ bitpos = bytesize * 8 - bitpos - bitsize;
oword &= ~(mask << bitpos);
oword |= fieldval << bitpos;
- store_unsigned_integer (addr, sizeof oword, byte_order, oword);
+ store_unsigned_integer (addr, bytesize, byte_order, oword);
}
\f
/* Pack NUM into BUF using a target format of TYPE. */
}
+/* Pack NUM into BUF using a target format of TYPE. */
+
+static void
+pack_unsigned_long (gdb_byte *buf, struct type *type, ULONGEST num)
+{
+ int len;
+ enum bfd_endian byte_order;
+
+ type = check_typedef (type);
+ len = TYPE_LENGTH (type);
+ byte_order = gdbarch_byte_order (get_type_arch (type));
+
+ switch (TYPE_CODE (type))
+ {
+ case TYPE_CODE_INT:
+ case TYPE_CODE_CHAR:
+ case TYPE_CODE_ENUM:
+ case TYPE_CODE_FLAGS:
+ case TYPE_CODE_BOOL:
+ case TYPE_CODE_RANGE:
+ case TYPE_CODE_MEMBERPTR:
+ store_unsigned_integer (buf, len, byte_order, num);
+ break;
+
+ case TYPE_CODE_REF:
+ case TYPE_CODE_PTR:
+ store_typed_address (buf, type, (CORE_ADDR) num);
+ break;
+
+ default:
+ error (_("Unexpected type (%d) encountered "
+ "for unsigned integer constant."),
+ TYPE_CODE (type));
+ }
+}
+
+
/* Convert C numbers into newly allocated values. */
struct value *
}
+/* Convert C unsigned numbers into newly allocated values. */
+
+struct value *
+value_from_ulongest (struct type *type, ULONGEST num)
+{
+ struct value *val = allocate_value (type);
+
+ pack_unsigned_long (value_contents_raw (val), type, num);
+
+ return val;
+}
+
+
/* Create a value representing a pointer of type TYPE to the address
ADDR. */
struct value *
const gdb_byte *valaddr,
CORE_ADDR address)
{
- struct value *v = allocate_value (type);
+ struct value *v;
if (valaddr == NULL)
- set_value_lazy (v, 1);
+ v = allocate_value_lazy (type);
else
- memcpy (value_contents_raw (v), valaddr, TYPE_LENGTH (type));
+ v = value_from_contents (type, valaddr);
set_value_address (v, address);
VALUE_LVAL (v) = lval_memory;
return v;
}
+/* Create a value of type TYPE holding the contents CONTENTS.
+ The new value is `not_lval'. */
+
+struct value *
+value_from_contents (struct type *type, const gdb_byte *contents)
+{
+ struct value *result;
+
+ result = allocate_value (type);
+ memcpy (value_contents_raw (result), contents, TYPE_LENGTH (type));
+ return result;
+}
+
struct value *
value_from_double (struct type *type, DOUBLEST num)
{
return val;
}
+/* Extract a value from the history file. Input will be of the form
+ $digits or $$digits. See block comment above 'write_dollar_variable'
+ for details. */
+
+struct value *
+value_from_history_ref (char *h, char **endp)
+{
+ int index, len;
+
+ if (h[0] == '$')
+ len = 1;
+ else
+ return NULL;
+
+ if (h[1] == '$')
+ len = 2;
+
+ /* Find length of numeral string. */
+ for (; isdigit (h[len]); len++)
+ ;
+
+ /* Make sure numeral string is not part of an identifier. */
+ if (h[len] == '_' || isalpha (h[len]))
+ return NULL;
+
+ /* Now collect the index value. */
+ if (h[1] == '$')
+ {
+ if (len == 2)
+ {
+ /* For some bizarre reason, "$$" is equivalent to "$$1",
+ rather than to "$$0" as it ought to be! */
+ index = -1;
+ *endp += len;
+ }
+ else
+ index = -strtol (&h[2], endp, 10);
+ }
+ else
+ {
+ if (len == 1)
+ {
+ /* "$" is equivalent to "$0". */
+ index = 0;
+ *endp += len;
+ }
+ else
+ index = strtol (&h[1], endp, 10);
+ }
+
+ return access_value_history (index);
+}
+
+struct value *
+coerce_ref_if_computed (const struct value *arg)
+{
+ const struct lval_funcs *funcs;
+
+ if (TYPE_CODE (check_typedef (value_type (arg))) != TYPE_CODE_REF)
+ return NULL;
+
+ if (value_lval_const (arg) != lval_computed)
+ return NULL;
+
+ funcs = value_computed_funcs (arg);
+ if (funcs->coerce_ref == NULL)
+ return NULL;
+
+ return funcs->coerce_ref (arg);
+}
+
+/* Look at value.h for description. */
+
+struct value *
+readjust_indirect_value_type (struct value *value, struct type *enc_type,
+ struct type *original_type,
+ struct value *original_value)
+{
+ /* Re-adjust type. */
+ deprecated_set_value_type (value, TYPE_TARGET_TYPE (original_type));
+
+ /* Add embedding info. */
+ set_value_enclosing_type (value, enc_type);
+ set_value_embedded_offset (value, value_pointed_to_offset (original_value));
+
+ /* We may be pointing to an object of some derived type. */
+ return value_full_object (value, NULL, 0, 0, 0);
+}
+
struct value *
coerce_ref (struct value *arg)
{
struct type *value_type_arg_tmp = check_typedef (value_type (arg));
+ struct value *retval;
+ struct type *enc_type;
- if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF)
- arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp),
- unpack_pointer (value_type (arg),
- value_contents (arg)));
- return arg;
+ retval = coerce_ref_if_computed (arg);
+ if (retval)
+ return retval;
+
+ if (TYPE_CODE (value_type_arg_tmp) != TYPE_CODE_REF)
+ return arg;
+
+ enc_type = check_typedef (value_enclosing_type (arg));
+ enc_type = TYPE_TARGET_TYPE (enc_type);
+
+ retval = value_at_lazy (enc_type,
+ unpack_pointer (value_type (arg),
+ value_contents (arg)));
+ return readjust_indirect_value_type (retval, enc_type,
+ value_type_arg_tmp, arg);
}
struct value *
switch (TYPE_CODE (type))
{
case TYPE_CODE_ARRAY:
- if (current_language->c_style_arrays)
+ if (!TYPE_VECTOR (type) && current_language->c_style_arrays)
arg = value_coerce_array (arg);
break;
case TYPE_CODE_FUNC:
}
\f
-/* Return true if the function returning the specified type is using
- the convention of returning structures in memory (passing in the
- address as a hidden first parameter). */
+/* Return the return value convention that will be used for the
+ specified type. */
-int
-using_struct_return (struct gdbarch *gdbarch,
- struct type *func_type, struct type *value_type)
+enum return_value_convention
+struct_return_convention (struct gdbarch *gdbarch,
+ struct value *function, struct type *value_type)
{
enum type_code code = TYPE_CODE (value_type);
if (code == TYPE_CODE_ERROR)
error (_("Function return type unknown."));
- if (code == TYPE_CODE_VOID)
+ /* Probe the architecture for the return-value convention. */
+ return gdbarch_return_value (gdbarch, function, value_type,
+ NULL, NULL, NULL);
+}
+
+/* Return true if the function returning the specified type is using
+ the convention of returning structures in memory (passing in the
+ address as a hidden first parameter). */
+
+int
+using_struct_return (struct gdbarch *gdbarch,
+ struct value *function, struct type *value_type)
+{
+ if (TYPE_CODE (value_type) == TYPE_CODE_VOID)
/* A void return value is never in memory. See also corresponding
code in "print_return_value". */
return 0;
- /* Probe the architecture for the return-value convention. */
- return (gdbarch_return_value (gdbarch, func_type, value_type,
- NULL, NULL, NULL)
+ return (struct_return_convention (gdbarch, function, value_type)
!= RETURN_VALUE_REGISTER_CONVENTION);
}
return val->initialized;
}
+/* Called only from the value_contents and value_contents_all()
+ macros, if the current data for a variable needs to be loaded into
+ value_contents(VAL). Fetches the data from the user's process, and
+ clears the lazy flag to indicate that the data in the buffer is
+ valid.
+
+ If the value is zero-length, we avoid calling read_memory, which
+ would abort. We mark the value as fetched anyway -- all 0 bytes of
+ it.
+
+ This function returns a value because it is used in the
+ value_contents macro as part of an expression, where a void would
+ not work. The value is ignored. */
+
+int
+value_fetch_lazy (struct value *val)
+{
+ gdb_assert (value_lazy (val));
+ allocate_value_contents (val);
+ if (value_bitsize (val))
+ {
+ /* To read a lazy bitfield, read the entire enclosing value. This
+ prevents reading the same block of (possibly volatile) memory once
+ per bitfield. It would be even better to read only the containing
+ word, but we have no way to record that just specific bits of a
+ value have been fetched. */
+ struct type *type = check_typedef (value_type (val));
+ enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
+ struct value *parent = value_parent (val);
+ LONGEST offset = value_offset (val);
+ LONGEST num;
+
+ if (value_lazy (parent))
+ value_fetch_lazy (parent);
+
+ if (!value_bits_valid (parent,
+ TARGET_CHAR_BIT * offset + value_bitpos (val),
+ value_bitsize (val)))
+ set_value_optimized_out (val, 1);
+ else if (!unpack_value_bits_as_long (value_type (val),
+ value_contents_for_printing (parent),
+ offset,
+ value_bitpos (val),
+ value_bitsize (val), parent, &num))
+ mark_value_bytes_unavailable (val,
+ value_embedded_offset (val),
+ TYPE_LENGTH (type));
+ else
+ store_signed_integer (value_contents_raw (val), TYPE_LENGTH (type),
+ byte_order, num);
+ }
+ else if (VALUE_LVAL (val) == lval_memory)
+ {
+ CORE_ADDR addr = value_address (val);
+ struct type *type = check_typedef (value_enclosing_type (val));
+
+ if (TYPE_LENGTH (type))
+ read_value_memory (val, 0, value_stack (val),
+ addr, value_contents_all_raw (val),
+ TYPE_LENGTH (type));
+ }
+ else if (VALUE_LVAL (val) == lval_register)
+ {
+ struct frame_info *frame;
+ int regnum;
+ struct type *type = check_typedef (value_type (val));
+ struct value *new_val = val, *mark = value_mark ();
+
+ /* Offsets are not supported here; lazy register values must
+ refer to the entire register. */
+ gdb_assert (value_offset (val) == 0);
+
+ while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val))
+ {
+ struct frame_id frame_id = VALUE_FRAME_ID (new_val);
+
+ frame = frame_find_by_id (frame_id);
+ regnum = VALUE_REGNUM (new_val);
+
+ gdb_assert (frame != NULL);
+
+ /* Convertible register routines are used for multi-register
+ values and for interpretation in different types
+ (e.g. float or int from a double register). Lazy
+ register values should have the register's natural type,
+ so they do not apply. */
+ gdb_assert (!gdbarch_convert_register_p (get_frame_arch (frame),
+ regnum, type));
+
+ new_val = get_frame_register_value (frame, regnum);
+
+ /* If we get another lazy lval_register value, it means the
+ register is found by reading it from the next frame.
+ get_frame_register_value should never return a value with
+ the frame id pointing to FRAME. If it does, it means we
+ either have two consecutive frames with the same frame id
+ in the frame chain, or some code is trying to unwind
+ behind get_prev_frame's back (e.g., a frame unwind
+ sniffer trying to unwind), bypassing its validations. In
+ any case, it should always be an internal error to end up
+ in this situation. */
+ if (VALUE_LVAL (new_val) == lval_register
+ && value_lazy (new_val)
+ && frame_id_eq (VALUE_FRAME_ID (new_val), frame_id))
+ internal_error (__FILE__, __LINE__,
+ _("infinite loop while fetching a register"));
+ }
+
+ /* If it's still lazy (for instance, a saved register on the
+ stack), fetch it. */
+ if (value_lazy (new_val))
+ value_fetch_lazy (new_val);
+
+ /* If the register was not saved, mark it optimized out. */
+ if (value_optimized_out (new_val))
+ set_value_optimized_out (val, 1);
+ else
+ {
+ set_value_lazy (val, 0);
+ value_contents_copy (val, value_embedded_offset (val),
+ new_val, value_embedded_offset (new_val),
+ TYPE_LENGTH (type));
+ }
+
+ if (frame_debug)
+ {
+ struct gdbarch *gdbarch;
+ frame = frame_find_by_id (VALUE_FRAME_ID (val));
+ regnum = VALUE_REGNUM (val);
+ gdbarch = get_frame_arch (frame);
+
+ fprintf_unfiltered (gdb_stdlog,
+ "{ value_fetch_lazy "
+ "(frame=%d,regnum=%d(%s),...) ",
+ frame_relative_level (frame), regnum,
+ user_reg_map_regnum_to_name (gdbarch, regnum));
+
+ fprintf_unfiltered (gdb_stdlog, "->");
+ if (value_optimized_out (new_val))
+ {
+ fprintf_unfiltered (gdb_stdlog, " ");
+ val_print_optimized_out (new_val, gdb_stdlog);
+ }
+ else
+ {
+ int i;
+ const gdb_byte *buf = value_contents (new_val);
+
+ if (VALUE_LVAL (new_val) == lval_register)
+ fprintf_unfiltered (gdb_stdlog, " register=%d",
+ VALUE_REGNUM (new_val));
+ else if (VALUE_LVAL (new_val) == lval_memory)
+ fprintf_unfiltered (gdb_stdlog, " address=%s",
+ paddress (gdbarch,
+ value_address (new_val)));
+ else
+ fprintf_unfiltered (gdb_stdlog, " computed");
+
+ fprintf_unfiltered (gdb_stdlog, " bytes=");
+ fprintf_unfiltered (gdb_stdlog, "[");
+ for (i = 0; i < register_size (gdbarch, regnum); i++)
+ fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
+ fprintf_unfiltered (gdb_stdlog, "]");
+ }
+
+ fprintf_unfiltered (gdb_stdlog, " }\n");
+ }
+
+ /* Dispose of the intermediate values. This prevents
+ watchpoints from trying to watch the saved frame pointer. */
+ value_free_to_mark (mark);
+ }
+ else if (VALUE_LVAL (val) == lval_computed
+ && value_computed_funcs (val)->read != NULL)
+ value_computed_funcs (val)->read (val);
+ /* Don't call value_optimized_out on val, doing so would result in a
+ recursive call back to value_fetch_lazy, instead check the
+ optimized_out flag directly. */
+ else if (val->optimized_out)
+ /* Keep it optimized out. */;
+ else
+ internal_error (__FILE__, __LINE__, _("Unexpected lazy value type."));
+
+ set_value_lazy (val, 0);
+ return 0;
+}
+
+/* Implementation of the convenience function $_isvoid. */
+
+static struct value *
+isvoid_internal_fn (struct gdbarch *gdbarch,
+ const struct language_defn *language,
+ void *cookie, int argc, struct value **argv)
+{
+ int ret;
+
+ if (argc != 1)
+ error (_("You must provide one argument for $_isvoid."));
+
+ ret = TYPE_CODE (value_type (argv[0])) == TYPE_CODE_VOID;
+
+ return value_from_longest (builtin_type (gdbarch)->builtin_int, ret);
+}
+
void
_initialize_values (void)
{
add_cmd ("convenience", no_class, show_convenience, _("\
-Debugger convenience (\"$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\
+Debugger convenience (\"$foo\") variables and functions.\n\
+Convenience variables are created when you assign them values;\n\
+thus, \"set $foo=1\" gives \"$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);
+\"$__\" holds the contents of the last address examined with \"x\"."
+#ifdef HAVE_PYTHON
+"\n\n\
+Convenience functions are defined via the Python API."
+#endif
+ ), &showlist);
+ add_alias_cmd ("conv", "convenience", no_class, 1, &showlist);
- add_cmd ("values", no_class, show_values,
- _("Elements of value history around item number IDX (or last ten)."),
+ add_cmd ("values", no_set_class, show_values, _("\
+Elements of value history around item number IDX (or last ten)."),
&showlist);
add_com ("init-if-undefined", class_vars, init_if_undefined_command, _("\
add_prefix_cmd ("function", no_class, function_command, _("\
Placeholder command for showing help on convenience functions."),
&functionlist, "function ", 0, &cmdlist);
+
+ add_internal_function ("_isvoid", _("\
+Check whether an expression is void.\n\
+Usage: $_isvoid (expression)\n\
+Return 1 if the expression is void, zero otherwise."),
+ isvoid_internal_fn, NULL);
}