This commits adds support for runtime detection of SIMD instructions. The idea is that you would build once with all supported SIMD functions and the same binaries could run on different machines with varying support for SIMD. At runtime gf-complete will select the right functions based on the processor.
gf_cpu.c has the logic to detect SIMD instructions. On Intel processors this is done through cpuid. For ARM on linux we use getauxv.
The logic in gf_w*.c has been changed to check for runtime SIMD support and fallback to generic code.
Also a new test has been added. It compares the functions selected by gf_init when we enable/disable SIMD support through build flags, with runtime enabling/disabling. The test checks if the results are identical.
There is currently no way to figure out which functions were selected
during gf_init and as a result of SIMD options. This is not even possible
in gdb since most functions are static.
This commit adds a new macro SET_FUNCTION that records the name of the
function selected during init inside the gf_internal structure. This macro
only works when DEBUG_FUNCTIONS is defined during compile. Otherwise the
code works exactly as it did before this change.
The names of selected functions will be used during testing of SIMD
runtime detection.
All calls such as:
gf->multiply.w32 = gf_w16_shift_multiply;
need to be replaced with the following:
SET_FUNCTION(gf,multiply,w32,gf_w16_shift_multiply)
Also added a new flag to tools/gf_methods that will print the names of
functions selected during gf_init.
* (1 << w) are changed into ((uint32_t)1 << w)
* int are changed into uint32_t
gf.c: gf_composite_get_default_poly:
a larger unsigned were assigned to unsigned integers in which case
the type of the assigned variable is changed to be the same as the
value assigned to it.
gf_w16.c: GF_MULTBY_TWO
setting the parameter to a variable instead of passing the expression
resolves the warning for some reason.
Signed-off-by: Loic Dachary <loic@dachary.org>
Fix for Coverity issue (from Ceph):
CID 1193089 (#1 of 1): Unintentional integer overflow (OVERFLOW_BEFORE_WIDEN)
overflow_before_widen: Potentially overflowing expression 1 << g_r with type
int (32 bits, signed) is evaluated using 32-bit arithmetic, and then used in
a context that expects an expression of type uint64_t (64 bits, unsigned).
CID 1193090 (#1 of 1): Unintentional integer overflow (OVERFLOW_BEFORE_WIDEN)
overflow_before_widen: Potentially overflowing expression 1 << g_s with type
int (32 bits, signed) is evaluated using 32-bit arithmetic, and then used in
a context that expects an expression of type uint64_t (64 bits, unsigned).
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Fix for Coverity issue (from Ceph):
CID 1193088 (#1 of 1): Unintentional integer overflow (OVERFLOW_BEFORE_WIDEN)
overflow_before_widen: Potentially overflowing expression 1 << g_s with type
int (32 bits, signed) is evaluated using 32-bit arithmetic, and then used in
a context that expects an expression of type uint64_t (64 bits, unsigned).
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Fix for Coverity issue (from Ceph):
CID 1193087 (#1 of 1): Unintentional integer overflow (OVERFLOW_BEFORE_WIDEN)
overflow_before_widen: Potentially overflowing expression 1 << g_r with type
int (32 bits, signed) is evaluated using 32-bit arithmetic, and then used
in a context that expects an expression of type uint64_t (64 bits, unsigned).
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Fix for Coverity issue (from Ceph):
CID 1193086 (#1 of 1): Unintentional integer overflow (OVERFLOW_BEFORE_WIDEN)
overflow_before_widen: Potentially overflowing expression 1 << g_r with type
int (32 bits, signed) is evaluated using 32-bit arithmetic, and then used in
a context that expects an expression of type uint64_t (64 bits, unsigned).
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Fix for Coverity issue:
CID 1297852 (#1 of 1): 'Constant'; variable guards dead code (DEADCODE)
dead_error_begin: Execution cannot reach this statement:
fprintf(stderr, "Code conta....
Local variable no_default_flag is assigned only once, to a constant value,
making it effectively constant throughout its scope. If this is not the
intent, examine the logic to see if there is a missing assignment that
would make no_default_flag not remain constant.
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
The 'm2' variable in gf_w64_clm_multiply_region_from_single_2() isn't
used except for calculations on 'm2' which are not used later in the code.
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Bassam Tabbara