+2011-02-14 Pedro Alves <pedro@codesourcery.com>
+
+ * value.h (unpack_bits_as_long): Delete declaration.
+ (unpack_value_bits_as_long): Declare.
+ (unpack_value_field_as_long): Declare.
+ (value_field_bitfield): Declare.
+ * value.c (unpack_bits_as_long): Rename to...
+ (unpack_value_bits_as_long_1): ... this. Add embedded_offset and
+ value parameters. Return the extracted result in a new output
+ parameter. If the value contents are unavailable, return false,
+ otherwise return true.
+ (unpack_value_bits_as_long): New.
+ (unpack_field_as_long): Rename to...
+ (unpack_value_field_as_long_1): ... this. Add embedded_offset and
+ Add embedded_offset and value parameters. Return the extracted
+ result in a new output parameter. If the value contents are
+ unavailable, return false, otherwise return true.
+ (unpack_value_field_as_long): New.
+ (unpack_field_as_long_1): New.
+ (unpack_field_as_long): Reimplement as wrapper around
+ unpack_value_field_as_long_1.
+ (value_field_bitfield): New function.
+ * valops.c (value_fetch_lazy): When fetching a bitfield, use
+ unpack_value_bits_as_long. Mark the value as unavailable, if it
+ is unavailable.
+ * jv-valprint.c (java_print_value_fields): Use
+ value_field_bitfield.
+ * p-valprint.c (pascal_object_print_value_fields): Use
+ value_field_bitfield.
+ * cp-valprint.c (cp_print_value_fields): Use value_field_bitfield.
+
2011-02-14 Pedro Alves <pedro@codesourcery.com>
* value.c (get_internalvar_integer): Also return the int value of
}
\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.
+/* 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. */
- If the field is signed, we also do sign extension. */
-
-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_bytes_available (original_value, embedded_offset + read_offset,
+ bytes_read))
+ return 0;
+
+ val = extract_unsigned_integer (valaddr + embedded_offset + read_offset,
bytes_read, byte_order);
/* Extract bits. See comment above. */
}
}
}
- 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
projects / binutils-gdb.git / commitdiff