path: root/src/string/armhf/memcpy.sub
diff options
authorRich Felker <>2013-08-14 03:06:21 -0400
committerRich Felker <>2013-08-14 03:06:21 -0400
commitcccc1844be95549e5b6c91ffc1f2c2ba3d3aab16 (patch)
treebf9cd7643d50131983f17d4631432b70db274d9c /src/string/armhf/memcpy.sub
parentfb72a97df9222be61ec582ba7b1e9ce496b65e3e (diff)
add arm-optimized memcpy implementation from bionic libc
the approach of this implementation was heavily investigated prior to adopting it. attempts to obtain similar performance with pure C code were capping out at about 75% of the performance of the asm, with considerably larger code size, and were fragile in that the compiler would sometimes compile part of memcpy into a call to itself. therefore, just using the asm seems to be the best option. this commit is the first to make use of the new subarch-specific asm framework. the new armel directory is the location for arm asm that should not be used for all arm subarchs, only the default one. armhf is the name of the little-endian hardfloat-ABI subarch, which can use the exact same asm. in both cases, the build system finds the asm by following a memcpy.sub file. the other two subarchs, armeb and armebhf, would need a big-endian variant of this code. it would not be hard to adapt the code to big endian, but I will hold off on doing so until there is demand for it.
Diffstat (limited to 'src/string/armhf/memcpy.sub')
1 files changed, 1 insertions, 0 deletions
diff --git a/src/string/armhf/memcpy.sub b/src/string/armhf/memcpy.sub
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