Fix unaligned access issues in host-network byte I/O on ARM #218
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1st1
approved these changes
Oct 30, 2017
Per report in #216 and https://bugs.debian.org/872408, the current implementation may raise SIGBUS on ARM platforms that do not support unaligned memory access. Fix this by using a stack variable and memcpy, which gives the compiler more opportunity to generate correct code. While at it, implement hton* and ntoh* in terms of byteswap intrinsics with an open-coded fallback. This drops the dependency on the platform's implementation, which might not necessarily be consistently fast. Smoke-tested locally on cross-compiled armv5tel-softfloat-linux-gnueabi and armv6j-hardfloat-linux-gnueabi with QEMU TCG. Fixes: #216.
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Per report in #216 and https://bugs.debian.org/872408, the current
implementation may raise SIGBUS on ARM platforms that do not support
unaligned memory access.
Fix this by using a stack variable and memcpy, which gives the compiler
more opportunity to generate correct code. While at it, implement
hton* and ntoh* in terms of byteswap intrinsics with an open-coded
fallback. This drops the dependency on the platform's implementation,
which might not necessarily be consistently fast.
Smoke-tested locally on cross-compiled armv5tel-softfloat-linux-gnueabi
and armv6j-hardfloat-linux-gnueabi with QEMU TCG.
Fixes: #216.