}
}
+/* Copy the ranges metadata in SRC that overlaps [SRC_BIT_OFFSET,
+ SRC_BIT_OFFSET+BIT_LENGTH) into DST, adjusted. */
+
+static void
+value_ranges_copy_adjusted (struct value *dst, int dst_bit_offset,
+ const struct value *src, int src_bit_offset,
+ int bit_length)
+{
+ ranges_copy_adjusted (&dst->unavailable, dst_bit_offset,
+ src->unavailable, src_bit_offset,
+ bit_length);
+ ranges_copy_adjusted (&dst->optimized_out, dst_bit_offset,
+ src->optimized_out, src_bit_offset,
+ bit_length);
+}
+
/* 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
dst_bit_offset = dst_offset * TARGET_CHAR_BIT;
bit_length = length * TARGET_CHAR_BIT;
- ranges_copy_adjusted (&dst->unavailable, dst_bit_offset,
- src->unavailable, src_bit_offset,
- bit_length);
-
- ranges_copy_adjusted (&dst->optimized_out, dst_bit_offset,
- src->optimized_out, src_bit_offset,
- bit_length);
+ value_ranges_copy_adjusted (dst, dst_bit_offset,
+ src, src_bit_offset,
+ bit_length);
}
/* Copy LENGTH bytes of SRC value's (all) contents
\f
-/* 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. */
+/* Unpack a bitfield of the specified FIELD_TYPE, from the object at
+ VALADDR, and store the result in *RESULT.
+ The bitfield starts at BITPOS bits and contains BITSIZE bits.
-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)
+ 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. */
+
+static LONGEST
+unpack_bits_as_long (struct type *field_type, const gdb_byte *valaddr,
+ int bitpos, int bitsize)
{
enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (field_type));
ULONGEST val;
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,
+ val = extract_unsigned_integer (valaddr + read_offset,
bytes_read, byte_order);
/* Extract bits. See comment above. */
}
}
- *result = val;
- return 1;
-}
-
-/* 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.
-
- 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_value_bits_as_long_1 (field_type, valaddr, embedded_offset,
- bitpos, bitsize, val,
- result);
+ return val;
}
/* Unpack a field FIELDNO of the specified TYPE, from the object at
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);
+ int bit_offset;
+
gdb_assert (val != NULL);
- return unpack_value_field_as_long_1 (type, valaddr, embedded_offset,
- fieldno, val, result);
+ bit_offset = embedded_offset * TARGET_CHAR_BIT + bitpos;
+ if (value_bits_any_optimized_out (val, bit_offset, bitsize)
+ || !value_bits_available (val, bit_offset, bitsize))
+ return 0;
+
+ *result = unpack_bits_as_long (field_type, valaddr + embedded_offset,
+ bitpos, bitsize);
+ return 1;
}
/* 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. */
+ object at VALADDR. See unpack_bits_as_long for more details. */
LONGEST
unpack_field_as_long (struct type *type, const gdb_byte *valaddr, int fieldno)
{
- 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);
- unpack_value_field_as_long_1 (type, valaddr, 0, fieldno, NULL, &result);
- return result;
+ return unpack_bits_as_long (field_type, valaddr, bitpos, bitsize);
+}
+
+/* Unpack a bitfield of BITSIZE bits found at BITPOS in the object at
+ VALADDR + EMBEDDEDOFFSET that has the type of DEST_VAL and store
+ the contents in DEST_VAL, zero or sign extending if the type of
+ DEST_VAL is wider than BITSIZE. VALADDR points to the contents of
+ VAL. If the VAL's contents required to extract the bitfield from
+ are unavailable/optimized out, DEST_VAL is correspondingly
+ marked unavailable/optimized out. */
+
+static void
+unpack_value_bitfield (struct value *dest_val,
+ int bitpos, int bitsize,
+ const gdb_byte *valaddr, int embedded_offset,
+ const struct value *val)
+{
+ enum bfd_endian byte_order;
+ int src_bit_offset;
+ int dst_bit_offset;
+ LONGEST num;
+ struct type *field_type = value_type (dest_val);
+
+ /* First, unpack and sign extend the bitfield as if it was wholly
+ available. Invalid/unavailable bits are read as zero, but that's
+ OK, as they'll end up marked below. */
+ byte_order = gdbarch_byte_order (get_type_arch (field_type));
+ num = unpack_bits_as_long (field_type, valaddr + embedded_offset,
+ bitpos, bitsize);
+ store_signed_integer (value_contents_raw (dest_val),
+ TYPE_LENGTH (field_type), byte_order, num);
+
+ /* Now copy the optimized out / unavailability ranges to the right
+ bits. */
+ src_bit_offset = embedded_offset * TARGET_CHAR_BIT + bitpos;
+ if (byte_order == BFD_ENDIAN_BIG)
+ dst_bit_offset = TYPE_LENGTH (field_type) * TARGET_CHAR_BIT - bitsize;
+ else
+ dst_bit_offset = 0;
+ value_ranges_copy_adjusted (dest_val, dst_bit_offset,
+ val, src_bit_offset, bitsize);
}
/* 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. */
+ from are unavailable/optimized out, the new value is
+ correspondingly marked unavailable/optimized out. */
struct value *
value_field_bitfield (struct type *type, int fieldno,
const gdb_byte *valaddr,
int embedded_offset, const struct value *val)
{
- LONGEST l;
+ int bitpos = TYPE_FIELD_BITPOS (type, fieldno);
+ int bitsize = TYPE_FIELD_BITSIZE (type, fieldno);
+ struct value *res_val = allocate_value (TYPE_FIELD_TYPE (type, fieldno));
- 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);
- }
+ unpack_value_bitfield (res_val, bitpos, bitsize,
+ valaddr, embedded_offset, val);
+
+ return res_val;
}
/* Modify the value of a bitfield. ADDR points to a block of memory in
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_any_optimized_out (parent,
- TARGET_CHAR_BIT * offset + value_bitpos (val),
- value_bitsize (val)))
- mark_value_bytes_optimized_out (val, value_embedded_offset (val),
- TYPE_LENGTH (type));
- 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);
+ unpack_value_bitfield (val,
+ value_bitpos (val), value_bitsize (val),
+ value_contents_for_printing (parent),
+ value_offset (val), parent);
}
else if (VALUE_LVAL (val) == lval_memory)
{
projects / binutils-gdb.git / commitdiff