[PATCH v2 1/2] lib/hash: initialize __m128i data type in a portable way

[Andre Muezerie <andremue@linux.microsoft.com>]

The mechanism used to initialize an __m128i data type in rte_thash.h is
non-portable and MSVC does not like it. It clearly is not doing what
is desired:

..\lib\hash\rte_thash.h(38): warning C4305: 'initializing':
    truncation from 'unsigned __int64' to 'char'
..\lib\hash\rte_thash.h(38): warning C4305: 'initializing':
    truncation from 'unsigned __int64' to 'char'

A more portable approach is to use compiler intrinsics to perform the
initialization. This patch uses a single compiler intrinsic to
initialize the data.

Signed-off-by: Andre Muezerie <andremue@linux.microsoft.com>
---
 lib/hash/rte_thash.h | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/lib/hash/rte_thash.h b/lib/hash/rte_thash.h
index 04f9f1875c..8bca430663 100644
--- a/lib/hash/rte_thash.h
+++ b/lib/hash/rte_thash.h
@@ -30,14 +30,6 @@
 extern "C" {
 #endif
 
-#ifdef RTE_ARCH_X86
-/* Byte swap mask used for converting IPv6 address
- * 4-byte chunks to CPU byte order
- */
-static const __m128i rte_thash_ipv6_bswap_mask = {
-		0x0405060700010203ULL, 0x0C0D0E0F08090A0BULL};
-#endif
-
 /**
  * length in dwords of input tuple to
  * calculate hash of ipv4 header only
@@ -159,6 +151,11 @@ rte_thash_load_v6_addrs(const struct rte_ipv6_hdr *orig,
 			union rte_thash_tuple *targ)
 {
 #ifdef RTE_ARCH_X86
+	/* Byte swap mask used for converting IPv6 address
+	 * 4-byte chunks to CPU byte order
+	 */
+	const __m128i rte_thash_ipv6_bswap_mask = _mm_set_epi64x(
+		0x0C0D0E0F08090A0BULL, 0x0405060700010203ULL);
 	__m128i ipv6 = _mm_loadu_si128((const __m128i *)&orig->src_addr);
 	*(__m128i *)&targ->v6.src_addr =
 			_mm_shuffle_epi8(ipv6, rte_thash_ipv6_bswap_mask);
-- 
2.48.1.vfs.0.0