// This resolver is shared between all three dispatch methods. It serves as
// the ifunc resolver if ifunc is supported, otherwise it is called as a
// regular function by the constructor or first call resolution methods.
-// The function attributes are needed for safe IFUNC resolver usage with GCC.
-lzma_resolver_attributes
+// The __no_profile_instrument_function__ attribute support is checked when
+// determining if ifunc can be used, so it is safe to use here.
+#ifdef CRC_USE_IFUNC
+__attribute__((__no_profile_instrument_function__))
+#endif
static crc32_func_type
crc32_resolve(void)
{
# endif
#endif
-#ifdef CRC_USE_IFUNC
-// Two function attributes are needed to make IFUNC safe with GCC.
-//
-// no-omit-frame-pointer prevents false Valgrind issues when combined with
-// a few other compiler flags. The optimize attribute is supported on
-// GCC >= 4.4 and is not supported with Clang.
-# if TUKLIB_GNUC_REQ(4,4) && !defined(__clang__)
-# define no_omit_frame_pointer \
- __attribute__((optimize("no-omit-frame-pointer")))
-# else
-# define no_omit_frame_pointer
-# endif
-
-// The __no_profile_instrument_function__ attribute support is checked when
-// determining if ifunc can be used, so it is safe to use unconditionally.
-// This attribute is needed because GCC can add profiling to the IFUNC
-// resolver, which calls functions that have not yet been relocated leading
-// to a crash on liblzma start up.
-# define lzma_resolver_attributes \
- __attribute__((__no_profile_instrument_function__)) \
- no_omit_frame_pointer
-#else
-# define lzma_resolver_attributes
-#endif
-
// For CRC32 use the generic slice-by-eight implementation if no optimized
// version is available.
#if !defined(CRC32_ARCH_OPTIMIZED) && !defined(CRC32_GENERIC)
good-0catpad-empty.xz has two zero-Block Streams concatenated with
four-byte Stream Padding between the Streams.
- good-2cat.xz has two Streams with one Block each.
-
good-1-check-none.xz has one Stream with one Block with two
uncompressed LZMA2 chunks and no integrity check.
good-1-arm64-lzma2-2.xz is like good-1-arm64-lzma2-1.xz but with
non-zero start offset. XZ Embedded doesn't support this file.
- good-1-riscv-lzma2-1.xz uses the RISC-V filter and LZMA2. The
- uncompressed data is constructed so it tests all of the instructions
- that should be encoded and a few that should not. Additionally, the
- file contains random bytes to help test unforeseen corner cases.
-
- good-1-riscv-lzma2-2.xz is like good-1-riscv-lzma2-1.xz but with
- non-zero start offset. XZ Embedded doesn't support this file.
-
good-1-lzma2-1.xz has two LZMA2 chunks, of which the second sets
new properties.
Uncompressed Size bytes of output will have been produced but
the LZMA2 decoder doesn't indicate end of stream.
- bad-3-corrupt_lzma2.xz has three Streams in it. The first and third
- streams are valid xz Streams. The middle Stream has a correct Stream
- Header, Block Header, Index and Stream Footer. Only the LZMA2 data
- is corrupt. This file should decompress if --single-stream is used.
-
3. Descriptions of Individual .lzma Files
will give an error at the end of the file after producing the
correct uncompressed output.
- good-small_compressed.lzma was created with a small dictionary (2^16).
- It contains the string "Hello World" repeated 100,000 times. This tests
- match decoding and wrapping the dictionary.
-
- good-large_compressed.lzma was created with a mix of repeated
- characters and random data to test a data stream containing many
- matches and many literals.
-
3.2. Bad Files
bad-too_small_size-without_eopm-3.lzma is like -1 above but instead
of a literal the problem occurs in the middle of a match.
- bad-dict_size.lzma has a valid dictionary size according to the .lzma
- File Format, but will be rejected by XZ Utils because it is not 2^n or
- 2^n + 2^(n-1).
-
4. Descriptions of Individual .lz (lzip) Files
projects / thirdparty / xz.git / commitdiff
