}
}
-#if GDB_SELF_TEST
-
-namespace selftests {
-
-/* Helper function for the unit test of copy_bitwise. Convert NBITS bits
- out of BITS, starting at OFFS, to the respective '0'/'1'-string. MSB0
- specifies whether to assume big endian bit numbering. Store the
- resulting (not null-terminated) string at STR. */
-
-static void
-bits_to_str (char *str, const gdb_byte *bits, ULONGEST offs,
- ULONGEST nbits, int msb0)
-{
- unsigned int j;
- size_t i;
-
- for (i = offs / 8, j = offs % 8; nbits; i++, j = 0)
- {
- unsigned int ch = bits[i];
- for (; j < 8 && nbits; j++, nbits--)
- *str++ = (ch & (msb0 ? (1 << (7 - j)) : (1 << j))) ? '1' : '0';
- }
-}
-
-/* Check one invocation of copy_bitwise with the given parameters. */
-
-static void
-check_copy_bitwise (const gdb_byte *dest, unsigned int dest_offset,
- const gdb_byte *source, unsigned int source_offset,
- unsigned int nbits, int msb0)
-{
- size_t len = align_up (dest_offset + nbits, 8);
- char *expected = (char *) alloca (len + 1);
- char *actual = (char *) alloca (len + 1);
- gdb_byte *buf = (gdb_byte *) alloca (len / 8);
-
- /* Compose a '0'/'1'-string that represents the expected result of
- copy_bitwise below:
- Bits from [0, DEST_OFFSET) are filled from DEST.
- Bits from [DEST_OFFSET, DEST_OFFSET + NBITS) are filled from SOURCE.
- Bits from [DEST_OFFSET + NBITS, LEN) are filled from DEST.
-
- E.g., with:
- dest_offset: 4
- nbits: 2
- len: 8
- dest: 00000000
- source: 11111111
-
- We should end up with:
- buf: 00001100
- DDDDSSDD (D=dest, S=source)
- */
- bits_to_str (expected, dest, 0, len, msb0);
- bits_to_str (expected + dest_offset, source, source_offset, nbits, msb0);
-
- /* Fill BUF with data from DEST, apply copy_bitwise, and convert the
- result to a '0'/'1'-string. */
- memcpy (buf, dest, len / 8);
- copy_bitwise (buf, dest_offset, source, source_offset, nbits, msb0);
- bits_to_str (actual, buf, 0, len, msb0);
-
- /* Compare the resulting strings. */
- expected[len] = actual[len] = '\0';
- if (strcmp (expected, actual) != 0)
- error (_("copy_bitwise %s != %s (%u+%u -> %u)"),
- expected, actual, source_offset, nbits, dest_offset);
-}
-
-/* Unit test for copy_bitwise. */
-
-static void
-copy_bitwise_tests (void)
-{
- /* Data to be used as both source and destination buffers. The two
- arrays below represent the lsb0- and msb0- encoded versions of the
- following bit string, respectively:
- 00000000 00011111 11111111 01001000 10100101 11110010
- This pattern is chosen such that it contains:
- - constant 0- and 1- chunks of more than a full byte;
- - 0/1- and 1/0 transitions on all bit positions within a byte;
- - several sufficiently asymmetric bytes.
- */
- static const gdb_byte data_lsb0[] = {
- 0x00, 0xf8, 0xff, 0x12, 0xa5, 0x4f
- };
- static const gdb_byte data_msb0[] = {
- 0x00, 0x1f, 0xff, 0x48, 0xa5, 0xf2
- };
-
- constexpr size_t data_nbits = 8 * sizeof (data_lsb0);
- constexpr unsigned max_nbits = 24;
-
- /* Try all combinations of:
- lsb0/msb0 bit order (using the respective data array)
- X [0, MAX_NBITS] copy bit width
- X feasible source offsets for the given copy bit width
- X feasible destination offsets
- */
- for (int msb0 = 0; msb0 < 2; msb0++)
- {
- const gdb_byte *data = msb0 ? data_msb0 : data_lsb0;
-
- for (unsigned int nbits = 1; nbits <= max_nbits; nbits++)
- {
- const unsigned int max_offset = data_nbits - nbits;
-
- for (unsigned source_offset = 0;
- source_offset <= max_offset;
- source_offset++)
- {
- for (unsigned dest_offset = 0;
- dest_offset <= max_offset;
- dest_offset++)
- {
- check_copy_bitwise (data + dest_offset / 8,
- dest_offset % 8,
- data + source_offset / 8,
- source_offset % 8,
- nbits, msb0);
- }
- }
- }
-
- /* Special cases: copy all, copy nothing. */
- check_copy_bitwise (data_lsb0, 0, data_msb0, 0, data_nbits, msb0);
- check_copy_bitwise (data_msb0, 0, data_lsb0, 0, data_nbits, msb0);
- check_copy_bitwise (data, data_nbits - 7, data, 9, 0, msb0);
- }
-}
-
-} /* namespace selftests */
-
-#endif /* GDB_SELF_TEST */
-
void
_initialize_utils (void)
{
#if GDB_SELF_TEST
selftests::register_test ("gdb_realpath", gdb_realpath_tests);
- selftests::register_test ("copy_bitwise", selftests::copy_bitwise_tests);
#endif
}
projects / external / binutils.git / blobdiff