Move the eight most common formats to the top of the list of image
formats and make create_random_image() much more likely to select one
of those eight formats.
This should help catch more bugs in SIMD optimized operations.
Green Hills Software MULTI compiler was producing a number
of warnings due to incorrect uses of int instead of the correct
corresponding pixman_*_t type.
The first broken optimization is that it checks "a != 0x00" where it
should check "s != 0x00". The other is that it skips the computation
when alpha is 0xff. That is wrong because in the formula:
min (1, (1 - Aa)/Ab)
the render specification states that if Ab is 0, the quotient is
defined to positive infinity. That is the case even if (1 - Aa) is 0.
The aligned_malloc() routine will be used in more than one test utility.
At least, a low-level blitter benchmark needs it. Therefore, let's make
this function a part of common test utilities code.
Added a pair of macros which can help to detect corruption
of floating point registers after a function call. This may
happen if _mm_empty() call is forgotten in MMX/SSE2 fast
path code, or ARM NEON assembly optimized function
forgets to save/restore d8-d15 registers before use.
The palettes for indexed formats must satisfy the condition that if
some index maps to a color C, then the 15 bit version of that color
must map back to the index. This ensures that the destination operator
is always a no-op, which seems like a reasonable assumption to make.
In some cases we end up trying to use the STORE_4 macro with an 8 bit
values, which resulted in other pixels getting overwritten. Fix this
by always masking off the low 4 bits.
This fixes blitters-test on big-endian machines.
When masking out the x bits, blitter-test would make the incorrect
assumption that the they were always in the topmost position. This is
not correct for formats of type PIXMAN_TYPE_BGRA.
The code and overall method is mostly based on scaling-test. This one
focuses on trying to stress as many different color formats and types
of composition operations as possible.
This is an initial implementation which may need more tuning. Also
not all color format and operator combinations are actually used.
When cpu specific optimizations are disabled, this test provides
identical deterministic results on x86, PPC and ARM.
Script blitters-test-bisect.rb now works in non-stop mode, until
it finds any problem. This allows to run it for example overnight
in order to test a lot more variants of pixman calls and increase
chances of detecting problems in pixman. Just like with scaling-test,
running blitters-test binary alone with no command line arguments
runs a small predefined number of tests and compares checksum
with a reference value for quick verification.
