/* 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, 2011 Free Software Foundation, Inc.
+ Copyright (C) 1986-2000, 2002-2012 Free Software Foundation, Inc.
This file is part of GDB.
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 which does not
+ actually exist in the program. */
+ 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;
/* Location of value (if lval). */
union
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. */
/* Register number if the value is from a register. */
short regnum;
- /* 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! */
- char lazy;
-
- /* If nonzero, this is the value of a variable which does not
- actually exist in the program. */
- char optimized_out;
-
- /* If value is a variable, is it initialized or not. */
- int initialized;
-
- /* 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;
-
/* Actual contents of the value. Target byte-order. NULL or not
valid if lazy is nonzero. */
gdb_byte *contents;
rather than available, since the common and default case is for a
value to be available. This is filled in at value read time. */
VEC(range_s) *unavailable;
-
- /* 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
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 = val->next;
val->next = NULL;
+ val->released = 1;
return;
}
{
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;
}