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 type using a sequence of 16 bytes stored in
memory.
There should be no perf degradation due to this change.
Signed-off-by: Andre Muezerie <andre...@linux.microsoft.com>
---
lib/hash/rte_thash.h | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/lib/hash/rte_thash.h b/lib/hash/rte_thash.h
index c0af5968df..3512639792 100644
--- a/lib/hash/rte_thash.h
+++ b/lib/hash/rte_thash.h
@@ -34,8 +34,9 @@ extern "C" {
/* 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};
+static const uint8_t rte_thash_ipv6_bswap_mask[] = {
+ 0x03, 0x02, 0x01, 0x00, 0x07, 0x06, 0x05, 0x04,
+ 0x0B, 0x0A, 0x09, 0x08, 0x0F, 0x0E, 0x0D, 0x0C};
#endif
/**
@@ -152,12 +153,14 @@ rte_thash_load_v6_addrs(const struct rte_ipv6_hdr *orig,
union rte_thash_tuple *targ)
{
#ifdef RTE_ARCH_X86
+ const __m128i ipv6_bswap_mask =
+ _mm_loadu_si128((const
__m128i*)&rte_thash_ipv6_bswap_mask);
__m128i ipv6 = _mm_loadu_si128((const __m128i *)&orig->src_addr);
*(__m128i *)&targ->v6.src_addr =
- _mm_shuffle_epi8(ipv6, rte_thash_ipv6_bswap_mask);
+ _mm_shuffle_epi8(ipv6, ipv6_bswap_mask);
ipv6 = _mm_loadu_si128((const __m128i *)&orig->dst_addr);
*(__m128i *)&targ->v6.dst_addr =
- _mm_shuffle_epi8(ipv6, rte_thash_ipv6_bswap_mask);
+ _mm_shuffle_epi8(ipv6, ipv6_bswap_mask);
#elif defined(__ARM_NEON)
uint8x16_t ipv6 = vld1q_u8(orig->src_addr.a);
vst1q_u8(targ->v6.src_addr.a, vrev32q_u8(ipv6));
--
2.34.1
