patch-2.1.9 linux/arch/alpha/lib/csum_ipv6_magic.S

• Lines: 69
• Date: Sun Nov 10 19:29:33 1996
• Orig file: v2.1.8/linux/arch/alpha/lib/csum_ipv6_magic.S
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v2.1.8/linux/arch/alpha/lib/csum_ipv6_magic.S linux/arch/alpha/lib/csum_ipv6_magic.S
@@ -0,0 +1,68 @@
+/*
+ * arch/alpha/lib/csum_ipv6_magic.S
+ * Contributed by Richard Henderson <rth@tamu.edu>
+ *
+ * unsigned short csum_ipv6_magic(struct in6_addr *saddr,
+ *                                struct in6_addr *daddr,
+ *                                __u16 len,
+ *                                unsigned short proto,
+ *                                unsigned int csum);
+ */
+
+	.globl csum_ipv6_magic
+	.align 4
+	.ent csum_ipv6_magic
+	.frame $30,0,$26,0
+csum_ipv6_magic:
+	.prologue 0
+
+	ldq	$0,0($16)	# e0    : load src & dst addr words
+	zapnot	$20,15,$20	# .. e1 : zero extend incoming csum
+	extwh	$18,7,$4	# e0    : byte swap len & proto while we wait
+	ldq	$1,8($16)	# .. e1 :
+	extbl	$18,1,$18	# e0    :
+	ldq	$2,0($17)	# .. e1 :
+	extwh	$19,7,$5	# e0    :
+	ldq	$3,8($17)	# .. e1 :
+	extbl	$19,1,$19	# e0    :
+	or	$18,$4,$18	# .. e1 :
+	addq	$20,$0,$20	# e0    : begin summing the words
+	or	$19,$5,$19	# .. e1 :
+	sll	$18,48,$18	# e0    :
+	cmpult	$20,$0,$0	# .. e1 :
+	sll	$19,48,$19	# e0    :
+	addq	$20,$1,$20	# .. e1 :
+	sra	$18,32,$18	# e0    : len complete
+	cmpult	$20,$1,$1	# .. e1 :
+	sra	$19,32,$19	# e0    : proto complete
+	addq	$20,$2,$20	# .. e1 :
+	cmpult	$20,$2,$2	# e0    :
+	addq	$20,$3,$20	# .. e1 :
+	cmpult	$20,$3,$3	# e0    :
+	addq	$20,$18,$20	# .. e1 :
+	cmpult	$20,$18,$18	# e0    :
+	addq	$20,$19,$20	# .. e1 :
+	cmpult	$20,$19,$19	# e0    :
+	addq	$0,$1,$0	# .. e1 : merge the carries back into the csum
+	addq	$2,$3,$2	# e0    :
+	addq	$18,$19,$18	# .. e1 :
+	addq	$0,$2,$0	# e0    :
+	addq	$20,$18,$20	# .. e1 :
+	addq	$0,$20,$0	# e0    :
+	unop			#       :
+	extwl	$0,2,$2		# e0    : begin folding the 64-bit value
+	zapnot	$0,3,$3		# .. e1 :
+	extwl	$0,4,$1		# e0    :
+	addq	$2,$3,$3	# .. e1 :
+	extwl	$0,6,$0		# e0    :
+	addq	$3,$1,$3	# .. e1 :
+	addq	$0,$3,$0	# e0    :
+	unop			#       :
+	extwl	$0,2,$1		# e0    :
+	zapnot	$0,3,$0		# .. e1 :
+	addq	$0,$1,$0	# e0    :
+	unop			#       :
+	not	$0,$0		# e0    :
+	ret			# .. e1 :
+
+	.end csum_ipv6_magic