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From: Cyril Chemparathy <cchemparathy@ezchip.com>
To: dev@dpdk.org
Subject: [dpdk-dev] [PATCH 03/10] hash: silence -Wcast-align on pointer arithmetic
Date: Wed, 29 Apr 2015 09:15:27 -0700	[thread overview]
Message-ID: <1430324134-25654-4-git-send-email-cchemparathy@ezchip.com> (raw)
In-Reply-To: <1430324134-25654-1-git-send-email-cchemparathy@ezchip.com>

Since sig_tbl_bucket_size and key_tbl_key_size are explicitly aligned at
initialization, offset dereferences in the hash table code cannot possibly be
unaligned.  However, the compiler is unaware of this fact and complains on
-Wcast-align.  This patch modifies the code to use RTE_PTR_ADD(), thereby
silencing the compiler by casting through (void *).

Signed-off-by: Cyril Chemparathy <cchemparathy@ezchip.com>
---
 lib/librte_hash/rte_hash.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/librte_hash/rte_hash.c b/lib/librte_hash/rte_hash.c
index 9245716..67dff5b 100644
--- a/lib/librte_hash/rte_hash.c
+++ b/lib/librte_hash/rte_hash.c
@@ -96,23 +96,23 @@ EAL_REGISTER_TAILQ(rte_hash_tailq)
 static inline hash_sig_t *
 get_sig_tbl_bucket(const struct rte_hash *h, uint32_t bucket_index)
 {
-	return (hash_sig_t *)
-			&(h->sig_tbl[bucket_index * h->sig_tbl_bucket_size]);
+	return RTE_PTR_ADD(h->sig_tbl, (bucket_index *
+					h->sig_tbl_bucket_size));
 }
 
 /* Returns a pointer to the first key in specified bucket. */
 static inline uint8_t *
 get_key_tbl_bucket(const struct rte_hash *h, uint32_t bucket_index)
 {
-	return (uint8_t *) &(h->key_tbl[bucket_index * h->bucket_entries *
-				     h->key_tbl_key_size]);
+	return RTE_PTR_ADD(h->key_tbl, (bucket_index * h->bucket_entries *
+					h->key_tbl_key_size));
 }
 
 /* Returns a pointer to a key at a specific position in a specified bucket. */
 static inline void *
 get_key_from_bucket(const struct rte_hash *h, uint8_t *bkt, uint32_t pos)
 {
-	return (void *) &bkt[pos * h->key_tbl_key_size];
+	return RTE_PTR_ADD(bkt, pos * h->key_tbl_key_size);
 }
 
 /* Does integer division with rounding-up of result. */
-- 
2.1.2

  parent reply	other threads:[~2015-04-29 16:15 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-04-29 16:15 [dpdk-dev] [PATCH 00/10] Improve cast alignment for strict aligned machines Cyril Chemparathy
2015-04-29 16:15 ` [dpdk-dev] [PATCH 01/10] eal: add and use unaligned integer types Cyril Chemparathy
2015-06-19 15:58   ` Olivier MATZ
2015-06-19 17:18     ` Cyril Chemparathy
2015-04-29 16:15 ` [dpdk-dev] [PATCH 02/10] mempool: silence -Wcast-align on pointer arithmetic Cyril Chemparathy
2015-04-29 16:15 ` Cyril Chemparathy [this message]
2015-04-29 16:15 ` [dpdk-dev] [PATCH 04/10] mbuf: " Cyril Chemparathy
2015-04-29 16:15 ` [dpdk-dev] [PATCH 05/10] ethdev: " Cyril Chemparathy
2015-04-29 16:15 ` [dpdk-dev] [PATCH 06/10] app/test-pmd: pack simple_gre_hdr Cyril Chemparathy
2015-04-29 16:15 ` [dpdk-dev] [PATCH 07/10] app/test: use struct ether_addr instead of a byte array cast Cyril Chemparathy
2015-04-29 16:15 ` [dpdk-dev] [PATCH 08/10] librte_mbuf: Add rte_pktmbuf_mtod_offset() Cyril Chemparathy
2015-06-19 15:58   ` Olivier MATZ
2015-06-19 17:18     ` Cyril Chemparathy
2015-04-29 16:15 ` [dpdk-dev] [PATCH 09/10] librte_mbuf: Add transform for rte_pktmbuf_mtod_offset() Cyril Chemparathy
2015-04-29 16:15 ` [dpdk-dev] [PATCH 10/10] librte_mbuf: Apply mtod-offset.cocci transform Cyril Chemparathy
2015-05-04  9:50 ` [dpdk-dev] [PATCH 00/10] Improve cast alignment for strict aligned machines Olivier MATZ
2015-05-04 17:26   ` Cyril Chemparathy

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