[PATCH v2] net/i40e: remove redundant judgment

[Feifei Wang]

Merged variable updates under the same condition. It reduces branch.

In ampere-altra, there is no performance improvement with this patch.
In x86 sse and avx2 path, there is also no performance improvement.


v2:
1. add change for avx and altivec path.

Suggested-by: Honnappa Nagarahalli <honnappa.nagarahalli at arm.com>
Signed-off-by: Feifei Wang <feifei.wang2 at arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang at arm.com>
---
 drivers/net/i40e/i40e_rxtx_common_avx.h  | 9 +++++----
 drivers/net/i40e/i40e_rxtx_vec_altivec.c | 9 +++++----
 drivers/net/i40e/i40e_rxtx_vec_neon.c    | 9 +++++----
 drivers/net/i40e/i40e_rxtx_vec_sse.c     | 9 +++++----
 4 files changed, 20 insertions(+), 16 deletions(-)

diff --git a/drivers/net/i40e/i40e_rxtx_common_avx.h b/drivers/net/i40e/i40e_rxtx_common_avx.h
index cfc1e63173..85958d6c81 100644
--- a/drivers/net/i40e/i40e_rxtx_common_avx.h
+++ b/drivers/net/i40e/i40e_rxtx_common_avx.h
@@ -198,14 +198,15 @@ i40e_rxq_rearm_common(struct i40e_rx_queue *rxq, __rte_unused bool avx512)
 #endif
 
 	rxq->rxrearm_start += RTE_I40E_RXQ_REARM_THRESH;
-	if (rxq->rxrearm_start >= rxq->nb_rx_desc)
+	rx_id = rxq->rxrearm_start - 1;
+
+	if (unlikely(rxq->rxrearm_start >= rxq->nb_rx_desc)) {
 		rxq->rxrearm_start = 0;
+		rx_id = rxq->nb_rx_desc - 1;
+	}
 
 	rxq->rxrearm_nb -= RTE_I40E_RXQ_REARM_THRESH;
 
-	rx_id = (uint16_t)((rxq->rxrearm_start == 0) ?
-			     (rxq->nb_rx_desc - 1) : (rxq->rxrearm_start - 1));
-
 	/* Update the tail pointer on the NIC */
 	I40E_PCI_REG_WC_WRITE(rxq->qrx_tail, rx_id);
 }
diff --git a/drivers/net/i40e/i40e_rxtx_vec_altivec.c b/drivers/net/i40e/i40e_rxtx_vec_altivec.c
index 2dfa04599c..8672ad1c41 100644
--- a/drivers/net/i40e/i40e_rxtx_vec_altivec.c
+++ b/drivers/net/i40e/i40e_rxtx_vec_altivec.c
@@ -89,14 +89,15 @@ i40e_rxq_rearm(struct i40e_rx_queue *rxq)
 	}
 
 	rxq->rxrearm_start += RTE_I40E_RXQ_REARM_THRESH;
-	if (rxq->rxrearm_start >= rxq->nb_rx_desc)
+	rx_id = rxq->rxrearm_start - 1;
+
+	if (unlikely(rxq->rxrearm_start >= rxq->nb_rx_desc)) {
 		rxq->rxrearm_start = 0;
+		rx_id = rxq->nb_rx_desc - 1;
+	}
 
 	rxq->rxrearm_nb -= RTE_I40E_RXQ_REARM_THRESH;
 
-	rx_id = (uint16_t)((rxq->rxrearm_start == 0) ?
-			     (rxq->nb_rx_desc - 1) : (rxq->rxrearm_start - 1));
-
 	/* Update the tail pointer on the NIC */
 	I40E_PCI_REG_WRITE(rxq->qrx_tail, rx_id);
 }
diff --git a/drivers/net/i40e/i40e_rxtx_vec_neon.c b/drivers/net/i40e/i40e_rxtx_vec_neon.c
index 12e6f1cbcb..49391fe4c7 100644
--- a/drivers/net/i40e/i40e_rxtx_vec_neon.c
+++ b/drivers/net/i40e/i40e_rxtx_vec_neon.c
@@ -64,14 +64,15 @@ i40e_rxq_rearm(struct i40e_rx_queue *rxq)
 	}
 
 	rxq->rxrearm_start += RTE_I40E_RXQ_REARM_THRESH;
-	if (rxq->rxrearm_start >= rxq->nb_rx_desc)
+	rx_id = rxq->rxrearm_start - 1;
+
+	if (unlikely(rxq->rxrearm_start >= rxq->nb_rx_desc)) {
 		rxq->rxrearm_start = 0;
+		rx_id = rxq->nb_rx_desc - 1;
+	}
 
 	rxq->rxrearm_nb -= RTE_I40E_RXQ_REARM_THRESH;
 
-	rx_id = (uint16_t)((rxq->rxrearm_start == 0) ?
-			     (rxq->nb_rx_desc - 1) : (rxq->rxrearm_start - 1));
-
 	rte_io_wmb();
 	/* Update the tail pointer on the NIC */
 	I40E_PCI_REG_WRITE_RELAXED(rxq->qrx_tail, rx_id);
diff --git a/drivers/net/i40e/i40e_rxtx_vec_sse.c b/drivers/net/i40e/i40e_rxtx_vec_sse.c
index bdc979a839..baf83cb3df 100644
--- a/drivers/net/i40e/i40e_rxtx_vec_sse.c
+++ b/drivers/net/i40e/i40e_rxtx_vec_sse.c
@@ -77,14 +77,15 @@ i40e_rxq_rearm(struct i40e_rx_queue *rxq)
 	}
 
 	rxq->rxrearm_start += RTE_I40E_RXQ_REARM_THRESH;
-	if (rxq->rxrearm_start >= rxq->nb_rx_desc)
+	rx_id = rxq->rxrearm_start - 1;
+
+	if (unlikely(rxq->rxrearm_start >= rxq->nb_rx_desc)) {
 		rxq->rxrearm_start = 0;
+		rx_id = rxq->nb_rx_desc - 1;
+	}
 
 	rxq->rxrearm_nb -= RTE_I40E_RXQ_REARM_THRESH;
 
-	rx_id = (uint16_t)((rxq->rxrearm_start == 0) ?
-			     (rxq->nb_rx_desc - 1) : (rxq->rxrearm_start - 1));
-
 	/* Update the tail pointer on the NIC */
 	I40E_PCI_REG_WC_WRITE(rxq->qrx_tail, rx_id);
 }
-- 
2.25.1