/* 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.
#include "cli/cli-decode.h"
#include "exceptions.h"
#include "python/python.h"
-
+#include <ctype.h>
#include "tracepoint.h"
+#include "cp-abi.h"
/* Prototypes for exported functions. */
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
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;
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
i = VEC_lower_bound (range_s, value->unavailable, &newr, range_lessthan);
if (i > 0)
{
- struct range *bef = VEC_index (range_s, value->unavailable, i - i);
+ struct range *bef = VEC_index (range_s, value->unavailable, i - 1);
if (ranges_overlap (bef->offset, bef->length, offset, length))
{
const struct value *val2, int offset2,
int length)
{
- int org_len = length;
- int org_offset1 = offset1;
- int org_offset2 = offset2;
int idx1 = 0, idx2 = 0;
- int prev_avail;
/* This routine is used by printing routines, where we should
already have read the value. Note that we only know whether a
value chunk is available if we've tried to read it. */
gdb_assert (!val1->lazy && !val2->lazy);
- /* The offset from either ORG_OFFSET1 or ORG_OFFSET2 where the
- available contents we haven't compared yet start. */
- prev_avail = 0;
-
while (length > 0)
{
range_s *r1, *r2;
/* The usual case is for both values to be completely available. */
if (idx1 == -1 && idx2 == -1)
- return (memcmp (val1->contents + org_offset1 + prev_avail,
- val2->contents + org_offset2 + prev_avail,
- org_len - prev_avail) == 0);
+ return (memcmp (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;
/* Compare the _available_ contents. */
- if (memcmp (val1->contents + org_offset1 + prev_avail,
- val2->contents + org_offset2 + prev_avail,
- l2 - prev_avail) != 0)
+ if (memcmp (val1->contents + offset1,
+ val2->contents + offset2,
+ l1) != 0)
return 0;
- prev_avail += h1;
length -= h1;
offset1 += h1;
offset2 += h1;
struct value *
allocate_computed_value (struct type *type,
- struct lval_funcs *funcs,
+ const struct lval_funcs *funcs,
void *closure)
{
struct value *v = allocate_value_lazy (type);
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);
+
+ return retval;
+}
+
/* Accessor methods. */
struct value *
return result;
}
-/* Copy LENGTH bytes of SRC value's contents starting at SRC_OFFSET,
- into DST value's 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. */
+/* 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,
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,
}
}
-/* Copy LENGTH bytes of SRC value's contents starting at SRC_OFFSET
- byte, into DST value's 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. */
+/* 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,
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)
value_bits_synthetic_pointer (const struct value *value,
int offset, int length)
{
- if (value == NULL || value->lval != lval_computed
+ if (value->lval != lval_computed
|| !value->location.computed.funcs->check_synthetic_pointer)
return 0;
return value->location.computed.funcs->check_synthetic_pointer (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 (const struct value *value)
{
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);
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;
}
value_incref (val->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);
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);
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)
break;
case FIELD_LOC_KIND_PHYSNAME:
{
- char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (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);
description correctly. */
check_typedef (type);
- /* Handle packed fields */
-
- if (TYPE_FIELD_BITSIZE (arg_type, fieldno))
+ if (value_optimized_out (arg1))
+ v = allocate_optimized_out_value (type);
+ else 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;
/* This field is actually a base subobject, so preserve the
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);
+ boffset = baseclass_offset (arg_type, fieldno,
+ value_contents (arg1),
+ value_embedded_offset (arg1),
+ value_address (arg1),
+ arg1);
+
if (value_lazy (arg1))
v = allocate_value_lazy (value_enclosing_type (arg1));
else
}
v->type = type;
v->offset = value_offset (arg1);
- v->embedded_offset = (offset + value_embedded_offset (arg1)
- + TYPE_FIELD_BITPOS (arg_type, fieldno) / 8);
+ v->embedded_offset = offset + value_embedded_offset (arg1) + boffset;
}
else
{
{
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;
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 "$0". */
+ index = 0;
+ *endp += len;
+ }
+ else
+ index = strtol (&h[1], endp, 10);
+ }
+
+ return access_value_history (index);
+}
+
+struct value *
+coerce_ref_if_computed (const struct value *arg)
+{
+ const struct lval_funcs *funcs;
+
+ if (TYPE_CODE (check_typedef (value_type (arg))) != TYPE_CODE_REF)
+ return NULL;
+
+ if (value_lval_const (arg) != lval_computed)
+ return NULL;
+
+ funcs = value_computed_funcs (arg);
+ if (funcs->coerce_ref == NULL)
+ return NULL;
+
+ return funcs->coerce_ref (arg);
+}
+
+/* Look at value.h for description. */
+
+struct value *
+readjust_indirect_value_type (struct value *value, struct type *enc_type,
+ struct type *original_type,
+ struct value *original_value)
+{
+ /* Re-adjust type. */
+ deprecated_set_value_type (value, TYPE_TARGET_TYPE (original_type));
+
+ /* Add embedding info. */
+ set_value_enclosing_type (value, enc_type);
+ set_value_embedded_offset (value, value_pointed_to_offset (original_value));
+
+ /* We may be pointing to an object of some derived type. */
+ return value_full_object (value, NULL, 0, 0, 0);
+}
+
struct value *
coerce_ref (struct value *arg)
{
struct type *value_type_arg_tmp = check_typedef (value_type (arg));
+ struct value *retval;
+ struct type *enc_type;
- if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF)
- arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp),
- unpack_pointer (value_type (arg),
- value_contents (arg)));
- return arg;
+ retval = coerce_ref_if_computed (arg);
+ if (retval)
+ return retval;
+
+ if (TYPE_CODE (value_type_arg_tmp) != TYPE_CODE_REF)
+ return arg;
+
+ enc_type = check_typedef (value_enclosing_type (arg));
+ enc_type = TYPE_TARGET_TYPE (enc_type);
+
+ retval = value_at_lazy (enc_type,
+ unpack_pointer (value_type (arg),
+ value_contents (arg)));
+ return readjust_indirect_value_type (retval, enc_type,
+ value_type_arg_tmp, arg);
}
struct value *
\"$__\" holds the contents of the last address examined with \"x\"."),
&showlist);
- add_cmd ("values", no_class, show_values, _("\
+ add_cmd ("values", no_set_class, show_values, _("\
Elements of value history around item number IDX (or last ten)."),
&showlist);
projects / deliverable / binutils-gdb.git / blobdiff