microudp.c: avoid redundant accesses into multi-level structures

diff --git a/software/bios/microudp.c b/software/bios/microudp.c
index 721905f5d5d754cbf8cc42c5f5ce7323d9789ec9..1b263260c6a448d02dbac94c80d2480ff233edf6 100644 (file)
--- a/software/bios/microudp.c
+++ b/software/bios/microudp.c
@@ -128,39 +128,42 @@ static unsigned int cached_ip;
 
 static void process_arp(void)
 {
+       const struct arp_frame *rx_arp = &rxbuffer->frame.contents.arp;
+       struct arp_frame *tx_arp = &txbuffer->frame.contents.arp;
+
        if(rxlen < 68) return;
-       if(rxbuffer->frame.contents.arp.hwtype != ARP_HWTYPE_ETHERNET) return;
-       if(rxbuffer->frame.contents.arp.proto != ARP_PROTO_IP) return;
-       if(rxbuffer->frame.contents.arp.hwsize != 6) return;
-       if(rxbuffer->frame.contents.arp.protosize != 4) return;
-       if(rxbuffer->frame.contents.arp.opcode == ARP_OPCODE_REPLY) {
-               if(rxbuffer->frame.contents.arp.sender_ip == cached_ip) {
+       if(rx_arp->hwtype != ARP_HWTYPE_ETHERNET) return;
+       if(rx_arp->proto != ARP_PROTO_IP) return;
+       if(rx_arp->hwsize != 6) return;
+       if(rx_arp->protosize != 4) return;
+       if(rx_arp->opcode == ARP_OPCODE_REPLY) {
+               if(rx_arp->sender_ip == cached_ip) {
                        int i;
                        for(i=0;i<6;i++)
-                               cached_mac[i] = rxbuffer->frame.contents.arp.sender_mac[i];
+                               cached_mac[i] = rx_arp->sender_mac[i];
                }
                return;
        }
-       if(rxbuffer->frame.contents.arp.opcode == ARP_OPCODE_REQUEST) {
-               if(rxbuffer->frame.contents.arp.target_ip == my_ip) {
+       if(rx_arp->opcode == ARP_OPCODE_REQUEST) {
+               if(rx_arp->target_ip == my_ip) {
                        int i;
                        
                        fill_eth_header(&txbuffer->frame.eth_header,
-                               rxbuffer->frame.contents.arp.sender_mac,
+                               rx_arp->sender_mac,
                                my_mac,
                                ETHERTYPE_ARP);
                        txlen = 68;
-                       txbuffer->frame.contents.arp.hwtype = ARP_HWTYPE_ETHERNET;
-                       txbuffer->frame.contents.arp.proto = ARP_PROTO_IP;
-                       txbuffer->frame.contents.arp.hwsize = 6;
-                       txbuffer->frame.contents.arp.protosize = 4;
-                       txbuffer->frame.contents.arp.opcode = ARP_OPCODE_REPLY;
-                       txbuffer->frame.contents.arp.sender_ip = my_ip;
+                       tx_arp->hwtype = ARP_HWTYPE_ETHERNET;
+                       tx_arp->proto = ARP_PROTO_IP;
+                       tx_arp->hwsize = 6;
+                       tx_arp->protosize = 4;
+                       tx_arp->opcode = ARP_OPCODE_REPLY;
+                       tx_arp->sender_ip = my_ip;
                        for(i=0;i<6;i++)
-                               txbuffer->frame.contents.arp.sender_mac[i] = my_mac[i];
-                       txbuffer->frame.contents.arp.target_ip = rxbuffer->frame.contents.arp.sender_ip;
+                               tx_arp->sender_mac[i] = my_mac[i];
+                       tx_arp->target_ip = rx_arp->sender_ip;
                        for(i=0;i<6;i++)
-                               txbuffer->frame.contents.arp.target_mac[i] = rxbuffer->frame.contents.arp.sender_mac[i];
+                               tx_arp->target_mac[i] = rx_arp->sender_mac[i];
                        send_packet();
                }
                return;
@@ -171,6 +174,7 @@ static const unsigned char broadcast[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 
 int microudp_arp_resolve(unsigned int ip)
 {
+       struct arp_frame *arp = &txbuffer->frame.contents.arp;
        int i;
        int tries;
        int timeout;
@@ -190,17 +194,17 @@ int microudp_arp_resolve(unsigned int ip)
                                my_mac,
                                ETHERTYPE_ARP);
                txlen = 68;
-               txbuffer->frame.contents.arp.hwtype = ARP_HWTYPE_ETHERNET;
-               txbuffer->frame.contents.arp.proto = ARP_PROTO_IP;
-               txbuffer->frame.contents.arp.hwsize = 6;
-               txbuffer->frame.contents.arp.protosize = 4;
-               txbuffer->frame.contents.arp.opcode = ARP_OPCODE_REQUEST;
-               txbuffer->frame.contents.arp.sender_ip = my_ip;
+               arp->hwtype = ARP_HWTYPE_ETHERNET;
+               arp->proto = ARP_PROTO_IP;
+               arp->hwsize = 6;
+               arp->protosize = 4;
+               arp->opcode = ARP_OPCODE_REQUEST;
+               arp->sender_ip = my_ip;
                for(i=0;i<6;i++)
-                       txbuffer->frame.contents.arp.sender_mac[i] = my_mac[i];
-               txbuffer->frame.contents.arp.target_ip = ip;
+                       arp->sender_mac[i] = my_mac[i];
+               arp->target_ip = ip;
                for(i=0;i<6;i++)
-                       txbuffer->frame.contents.arp.target_mac[i] = 0;
+                       arp->target_mac[i] = 0;
                send_packet();
 
                /* Do we get a reply ? */