eal/x86: fix unaligned access for small memcpy

Calls to rte_memcpy for 1 < n < 16 could result in unaligned
loads/stores, which is undefined behaviour according to the C
standard, and strict aliasin

eal/x86: fix unaligned access for small memcpy

Calls to rte_memcpy for 1 < n < 16 could result in unaligned
loads/stores, which is undefined behaviour according to the C
standard, and strict aliasing violations.

The code was changed to use a packed structure that allows aliasing
(using the __may_alias__ attribute) to perform the load/store
operations. This results in code that has the same performance as the
original code and that is also C standards-compliant.

Fixes: af75078fece3 ("first public release")
Cc: [email protected]

Signed-off-by: Luc Pelletier <[email protected]>
Acked-by: Konstantin Ananyev <[email protected]>
Tested-by: Konstantin Ananyev <[email protected]>

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eal/x86: remove atomic header include loop

Remove the x86 top atomic header include from the architecture related
header file, since this x86 top atomic header file has included them.

Signed-off-by

eal/x86: remove atomic header include loop

Remove the x86 top atomic header include from the architecture related
header file, since this x86 top atomic header file has included them.

Signed-off-by: Haiyue Wang <[email protected]>

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fix spelling in comments and strings

The tool comes from https://github.com/jsoref

Signed-off-by: Josh Soref <[email protected]>
Signed-off-by: Thomas Monjalon <[email protected]>

eal/x86: avoid cast-align warning in memcpy functions

Functions and macros in x86 rte_memcpy.h may cause cast-align warnings,
when using strict cast align flag with supporting gcc:
gcc (Ubuntu 9.3.0

eal/x86: avoid cast-align warning in memcpy functions

Functions and macros in x86 rte_memcpy.h may cause cast-align warnings,
when using strict cast align flag with supporting gcc:
gcc (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0
CFLAGS="-Wcast-align=strict" make V=1 -C examples/l2fwd clean static

For example:
In file included from main.c:24:
/dpdk/build/include/rte_memcpy.h: In function 'rte_mov16':
/dpdk/build/include/rte_memcpy.h:306:25: warning: cast increases
required alignment of target type [-Wcast-align]
306 | xmm0 = _mm_loadu_si128((const __m128i *)src);
| ^

As the code assumes correct alignment, add first a (void *) or (const
void *) castings, to avoid the warnings.

Fixes: 9484092baad3 ("eal/x86: optimize memcpy for AVX512 platforms")
Cc: [email protected]

Signed-off-by: Eli Britstein <[email protected]>

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