2012-08-15 Liubov Dmitrieva <liubov.dmitrieva@gmail.com>
[BZ #14195]
* sysdeps/i386/i686/multiarch/strcmp-sssse3.S: Fix
segmentation fault for a case of two empty input strings.
* string/test-strncasecmp.c (check1): Renamed to...
(bz12205): ...this.
(bz14195): Add new testcase for two empty input strings and N > 0.
(test_main): Call new testcase, adapt for renamed function.
Fixes:
In file included from ../sysdeps/i386/i686/multiarch/wcschr-c.c:8:0:
../wcsmbs/wcschr.c:26:1: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
../wcsmbs/wcschr.c:37:1: warning: data definition has no type or storage class [enabled by default]
../wcsmbs/wcschr.c:37:1: warning: type defaults to ‘int’ in declaration of ‘__hidden_ver1’ [enabled by default]
../wcsmbs/wcschr.c:37:1: warning: parameter names (without types) in function declaration [enabled by default]
I've improved the following implementation of memcpy:
"sysdeps/i386/i686/multiarch/memcpy-ssse3.S".
The patch includes some minor style fixes, but the important part is
just using prefetch loops for the case:
DATA_CACHE_SIZE_HALF <= len < SHARED_CACHE_SIZE_HALF and
src and dst pointers have unequal 16 byte alignments.
This gives from 6% - 50% performance boost on the atom machine, about
24,73% in geometric mean.
Wrong copy algorithm for last bytes, not thread safety.
In some particular cases it uses the destination
memory beyond the string end for
16-byte load, puts changes into that part that is relevant
to destination string and writes whole 16-byte chunk into memory.
I have a test case where the memory beyond the string end contains
malloc/free data, that appear corrupted in case free() updates
it in between the 16-byte read and 16-byte write.