Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * arch/alpha/lib/csum_ipv6_magic.S | |
3 | * Contributed by Richard Henderson <rth@tamu.edu> | |
4 | * | |
5 | * unsigned short csum_ipv6_magic(struct in6_addr *saddr, | |
6 | * struct in6_addr *daddr, | |
7 | * __u32 len, | |
8 | * unsigned short proto, | |
9 | * unsigned int csum); | |
10 | */ | |
11 | ||
12 | .globl csum_ipv6_magic | |
13 | .align 4 | |
14 | .ent csum_ipv6_magic | |
15 | .frame $30,0,$26,0 | |
16 | csum_ipv6_magic: | |
17 | .prologue 0 | |
18 | ||
19 | ldq $0,0($16) # e0 : load src & dst addr words | |
20 | zapnot $20,15,$20 # .. e1 : zero extend incoming csum | |
21 | extqh $18,1,$4 # e0 : byte swap len & proto while we wait | |
22 | ldq $1,8($16) # .. e1 : | |
23 | ||
24 | extbl $18,1,$5 # e0 : | |
25 | ldq $2,0($17) # .. e1 : | |
26 | extbl $18,2,$6 # e0 : | |
27 | ldq $3,8($17) # .. e1 : | |
28 | ||
29 | extbl $18,3,$18 # e0 : | |
30 | sra $4,32,$4 # e0 : | |
31 | sll $5,16,$5 # e0 : | |
32 | addq $20,$0,$20 # .. e1 : begin summing the words | |
33 | ||
34 | sll $6,8,$6 # e0 : | |
35 | cmpult $20,$0,$0 # .. e1 : | |
36 | extwh $19,7,$7 # e0 : | |
37 | or $4,$18,$18 # .. e1 : | |
38 | ||
39 | extbl $19,1,$19 # e0 : | |
40 | or $5,$6,$5 # .. e1 : | |
41 | or $18,$5,$18 # e0 : len complete | |
42 | or $19,$7,$19 # .. e1 : | |
43 | ||
44 | sll $19,48,$19 # e0 : | |
45 | addq $20,$1,$20 # .. e1 : | |
46 | sra $19,32,$19 # e0 : proto complete | |
47 | cmpult $20,$1,$1 # .. e1 : | |
48 | ||
49 | nop # e0 : | |
50 | addq $20,$2,$20 # .. e1 : | |
51 | cmpult $20,$2,$2 # e0 : | |
52 | addq $20,$3,$20 # .. e1 : | |
53 | ||
54 | cmpult $20,$3,$3 # e0 : | |
55 | addq $20,$18,$20 # .. e1 : | |
56 | cmpult $20,$18,$18 # e0 : | |
57 | addq $20,$19,$20 # .. e1 : | |
58 | ||
59 | cmpult $20,$19,$19 # e0 : | |
60 | addq $0,$1,$0 # .. e1 : merge the carries back into the csum | |
61 | addq $2,$3,$2 # e0 : | |
62 | addq $18,$19,$18 # .. e1 : | |
63 | ||
64 | addq $0,$2,$0 # e0 : | |
65 | addq $20,$18,$20 # .. e1 : | |
66 | addq $0,$20,$0 # e0 : | |
67 | unop # : | |
68 | ||
69 | extwl $0,2,$2 # e0 : begin folding the 64-bit value | |
70 | zapnot $0,3,$3 # .. e1 : | |
71 | extwl $0,4,$1 # e0 : | |
72 | addq $2,$3,$3 # .. e1 : | |
73 | ||
74 | extwl $0,6,$0 # e0 : | |
75 | addq $3,$1,$3 # .. e1 : | |
76 | addq $0,$3,$0 # e0 : | |
77 | unop # : | |
78 | ||
79 | extwl $0,2,$1 # e0 : fold 18-bit value | |
80 | zapnot $0,3,$0 # .. e1 : | |
81 | addq $0,$1,$0 # e0 : | |
82 | unop # : | |
83 | ||
84 | extwl $0,2,$1 # e0 : fold 17-bit value | |
85 | zapnot $0,3,$0 # .. e1 : | |
86 | addq $0,$1,$0 # e0 : | |
87 | not $0,$0 # e1 : and complement. | |
88 | ||
89 | zapnot $0,3,$0 # e0 : | |
90 | ret # .. e1 : | |
91 | ||
92 | .end csum_ipv6_magic |