Following up on the previous commit by Martin Storsjö:
If the availability of ARM Neon is not only known at compile time,
but also expected by the compiler's target architecture, there should
be no further need for a run-time check. In fact, such a check would
be counter-productive.
ARM Neon is expected to be unconditionally available on ARM64.
Issue an #error if PNG_ARM_NEON_CHECK_SUPPORTED is defined on an
ARM64-based platform.
For the plain ARM platforms where ARM Neon checking is not yet
implemented, issue a slightly more descriptive #error, including
a suggested course of action.
MSVC's <arm64_neon.h> header contains cl.exe intrinsics that are not
recognized by clang-cl.
Contributed-by: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Contributed-by: Mike Klein <mtklein@google.com>
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Move deallocation of riffled_palette from png_write_destroy to
png_read_destroy. The reader (not the writer) is the owner of
riffled_palette.
Move allocation and initialization of riffled_palette from
png_do_read_transformations to png_init_palette_transformations.
Allow riffled_palette inside png_struct only if the ARM Neon
optimizations are enabled.
Rename png_riffle_palette_rgba to png_riffle_palette_rgba8, etc.,
to better indicate the strict applicability of these routines.
Fix an unused parameter warning in the build configurations where
riffled palette optimization is not enabled.
Fix indentation.
implementation of the ARM NEON discovery function to be set at
build-time and provide sample implementations from the current code in the
contrib/arm-neon subdirectory. The __linux__ code has also been changed to
compile and link on Android by using /proc/cpuinfo, and the old linux code
is in contrib/arm-neon/linux-auxv.c. The new code avoids POSIX and Linux
dependencies apart from opening /proc/cpuinfo and is C90 compliant.
or intrinsics to be turned on during the build by defining
PNG_ARM_NEON_IMPLEMENTATION to the correct value (2 or 1). The
default is "undefined" and the build type is selected in pngpriv.h.
