# contrib/arm/neon.dfa
#
# This is a dfa fragment that is added to DFA_HARDWARE in Makefile.am and
# consequently is inserted after scripts/pnglibconf.dfa to define extra,
# hardware, options.
#
# The following are required in any fragment to record the copyright holder of
# the *changes* and the appropriate email for bug reports.  Note that the
# copyright here is just for the specific configuration; additional files may
# have additional and/or different copyrights.
#
# Later settings (e.g. in user.dfa) will override these settings.
#
setting USER_PRIVATEBUILD default "John Bowler"
setting USER_BUG_REPORTS default "jbowler@acm.org"
#
# These options are specific to the ARM NEON hardware optimizations.  At present
# these optimizations depend on GCC specific pre-processing of an assembler (.S)
# file so they probably won't work with other compilers.
#
# ARM_NEON_OPT: unset: check at compile time (__ARM_NEON__ must be defined by
#                      the compiler, typically as a result of specifying
#                      CC="gcc -mfpu=neon".)
#                   0: disable (even if the CPU has a NEON FPU.)
#                   1: check at run time (via ARM_NEON_{API,CHECK})
#                   2: switch on unconditionally (inadvisable - instead pass
#                      -mfpu=neon to GCC in CC)
#           When building libpng avoid using any setting other than '0'; '1' is
#           set automatically when either 'API' or 'CHECK' are configured in,
#           '2' should not be necessary as -mfpu=neon will achieve the same
#           effect as well as applying NEON optimizations to the rest of the
#           libpng code.
#           NOTE: any setting other than '0' requires ALIGNED_MEMORY
# ARM_NEON_API:   (PNG_ARM_NEON == 1) allow the optimization to be switched on
#                 with png_set_option
# ARM_NEON_CHECK: (PNG_ARM_NEON == 1) compile a run-time check to see if Neon
#                 extensions are supported. This is poorly supported and
#                 deprecated - use the png_set_option API.
setting ARM_NEON_OPT
option ARM_NEON_API disabled enables SET_OPTION sets ARM_NEON_OPT 1
option ARM_NEON_CHECK disabled sets ARM_NEON_OPT 1