libpng/contrib/arm-neon/android-ndk.c
2014-03-06 12:49:17 -06:00

40 lines
1.3 KiB
C

/* contrib/arm-neon/android-ndk.c
*
* Copyright (c) 2014 Glenn Randers-Pehrson
* Written by John Bowler, 2014.
* Last changed in libpng 1.6.10 [March 6, 2014]
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*
* SEE contrib/arm-neon/README before reporting bugs
*
* STATUS: COMPILED, UNTESTED
* BUG REPORTS: png-mng-implement@sourceforge.net
*
* png_have_neon implemented for the Android NDK, see:
*
* Documentation:
* http://www.kandroid.org/ndk/docs/CPU-ARM-NEON.html
* http://code.google.com/p/android/issues/detail?id=49065
*
* NOTE: this requires that libpng is built against the Android NDK and linked
* with an implementation of the Android ARM 'cpu-features' library. The code
* has been compiled only, not linked: no version of the library has been found,
* only the header files exist in the NDK.
*/
#include <cpu-features.h>
static int
png_have_neon(png_structp png_ptr)
{
/* This is a whole lot easier than the linux code, however it is probably
* implemented as below, therefore it is better to cache the result (these
* function calls may be slow!)
*/
PNG_UNUSED(png_ptr)
return android_getCpuFamily() == ANDROID_CPU_FAMILY_ARM &&
(android_getCpuFeatures() & ANDROID_CPU_ARM_FEATURE_NEON) != 0;
}