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); | |
58ed2f9c IK |
10 | * |
11 | * Misalignment handling (which costs 16 instructions / 8 cycles) | |
12 | * added by Ivan Kokshaysky <ink@jurassic.park.msu.ru> | |
1da177e4 LT |
13 | */ |
14 | ||
15 | .globl csum_ipv6_magic | |
16 | .align 4 | |
17 | .ent csum_ipv6_magic | |
18 | .frame $30,0,$26,0 | |
19 | csum_ipv6_magic: | |
20 | .prologue 0 | |
21 | ||
58ed2f9c | 22 | ldq_u $0,0($16) # e0 : load src & dst addr words |
1da177e4 LT |
23 | zapnot $20,15,$20 # .. e1 : zero extend incoming csum |
24 | extqh $18,1,$4 # e0 : byte swap len & proto while we wait | |
58ed2f9c | 25 | ldq_u $21,7($16) # .. e1 : handle misalignment |
1da177e4 LT |
26 | |
27 | extbl $18,1,$5 # e0 : | |
58ed2f9c | 28 | ldq_u $1,8($16) # .. e1 : |
1da177e4 | 29 | extbl $18,2,$6 # e0 : |
58ed2f9c | 30 | ldq_u $22,15($16) # .. e1 : |
1da177e4 LT |
31 | |
32 | extbl $18,3,$18 # e0 : | |
58ed2f9c | 33 | ldq_u $2,0($17) # .. e1 : |
1da177e4 | 34 | sra $4,32,$4 # e0 : |
58ed2f9c IK |
35 | ldq_u $23,7($17) # .. e1 : |
36 | ||
37 | extql $0,$16,$0 # e0 : | |
38 | ldq_u $3,8($17) # .. e1 : | |
39 | extqh $21,$16,$21 # e0 : | |
40 | ldq_u $24,15($17) # .. e1 : | |
41 | ||
1da177e4 | 42 | sll $5,16,$5 # e0 : |
58ed2f9c IK |
43 | or $0,$21,$0 # .. e1 : 1st src word complete |
44 | extql $1,$16,$1 # e0 : | |
1da177e4 LT |
45 | addq $20,$0,$20 # .. e1 : begin summing the words |
46 | ||
58ed2f9c | 47 | extqh $22,$16,$22 # e0 : |
1da177e4 | 48 | cmpult $20,$0,$0 # .. e1 : |
58ed2f9c IK |
49 | sll $6,8,$6 # e0 : |
50 | or $1,$22,$1 # .. e1 : 2nd src word complete | |
1da177e4 | 51 | |
58ed2f9c IK |
52 | extql $2,$17,$2 # e0 : |
53 | or $4,$18,$18 # .. e1 : | |
54 | extqh $23,$17,$23 # e0 : | |
1da177e4 | 55 | or $5,$6,$5 # .. e1 : |
1da177e4 | 56 | |
58ed2f9c IK |
57 | extql $3,$17,$3 # e0 : |
58 | or $2,$23,$2 # .. e1 : 1st dst word complete | |
59 | extqh $24,$17,$24 # e0 : | |
60 | or $18,$5,$18 # .. e1 : len complete | |
61 | ||
62 | extwh $19,7,$7 # e0 : | |
63 | or $3,$24,$3 # .. e1 : 2nd dst word complete | |
64 | extbl $19,1,$19 # e0 : | |
1da177e4 | 65 | addq $20,$1,$20 # .. e1 : |
58ed2f9c IK |
66 | |
67 | or $19,$7,$19 # e0 : | |
1da177e4 | 68 | cmpult $20,$1,$1 # .. e1 : |
58ed2f9c IK |
69 | sll $19,48,$19 # e0 : |
70 | nop # .. e0 : | |
1da177e4 | 71 | |
58ed2f9c | 72 | sra $19,32,$19 # e0 : proto complete |
1da177e4 LT |
73 | addq $20,$2,$20 # .. e1 : |
74 | cmpult $20,$2,$2 # e0 : | |
75 | addq $20,$3,$20 # .. e1 : | |
76 | ||
77 | cmpult $20,$3,$3 # e0 : | |
78 | addq $20,$18,$20 # .. e1 : | |
79 | cmpult $20,$18,$18 # e0 : | |
80 | addq $20,$19,$20 # .. e1 : | |
81 | ||
82 | cmpult $20,$19,$19 # e0 : | |
83 | addq $0,$1,$0 # .. e1 : merge the carries back into the csum | |
84 | addq $2,$3,$2 # e0 : | |
85 | addq $18,$19,$18 # .. e1 : | |
86 | ||
87 | addq $0,$2,$0 # e0 : | |
88 | addq $20,$18,$20 # .. e1 : | |
89 | addq $0,$20,$0 # e0 : | |
90 | unop # : | |
91 | ||
92 | extwl $0,2,$2 # e0 : begin folding the 64-bit value | |
93 | zapnot $0,3,$3 # .. e1 : | |
94 | extwl $0,4,$1 # e0 : | |
95 | addq $2,$3,$3 # .. e1 : | |
96 | ||
97 | extwl $0,6,$0 # e0 : | |
98 | addq $3,$1,$3 # .. e1 : | |
99 | addq $0,$3,$0 # e0 : | |
100 | unop # : | |
101 | ||
102 | extwl $0,2,$1 # e0 : fold 18-bit value | |
103 | zapnot $0,3,$0 # .. e1 : | |
104 | addq $0,$1,$0 # e0 : | |
105 | unop # : | |
106 | ||
107 | extwl $0,2,$1 # e0 : fold 17-bit value | |
108 | zapnot $0,3,$0 # .. e1 : | |
109 | addq $0,$1,$0 # e0 : | |
58ed2f9c | 110 | not $0,$0 # .. e1 : and complement. |
1da177e4 LT |
111 | |
112 | zapnot $0,3,$0 # e0 : | |
113 | ret # .. e1 : | |
114 | ||
115 | .end csum_ipv6_magic |